// Scorehand -- MuseScore 4 plugin, chat-sidebar edition.
// Author: AiHud (https://scorehand.aihud.net, hi@aihud.net)
// Copyright (C) 2026 AiHud. Licensed under the GNU GPL v3 or later:
// https://scorehand.aihud.net/LICENSE  Source: https://scorehand.aihud.net/source
//
// DOCKING: MuseScore Studio 4.7.5 cannot dock plugins. The legacy loader maps
// pluginType "dock" to the same floating dialog as "dialog" (verified empirically
// 2026-10-22), and PluginAPI.dockArea is a deprecated no-op. Real docked panels were
// only added to MuseScore's master branch in Oct 2026 (muse_framework ExtensionPanel,
// pluginType "dock"); this file already declares pluginType "dock", so on such a
// build it should dock automatically. On 4.7.x the window instead re-positions itself
// as a full-height sidebar flush with the right edge of the MuseScore window and
// stays open across requests (it is non-modal).
//
// Flow per message: export the OPEN score to MusicXML -> hosted mode: POST it to
// <serverUrl>/v1/edit with the Scorehand key (XMLHttpRequest); local mode: run copilot.py via a
// launcher script (QProcess.startWithArgs, non-blocking, polled) -> show reply / clarifying
// question with option buttons -> apply the returned edit list IN PLACE to the open score
// inside one startCmd()/endCmd(), so a single Ctrl+Z undoes the whole request. Every request
// re-exports the score, so follow-ups build on it, including any manual edits.
//
// Install: copy into ~/Documents/MuseScore4/Plugins/Scorehand/, restart MuseScore,
// Home > Plugins > Scorehand > Enable. Run: Plugins > Composing/arranging tools > Scorehand.
import QtQuick 2.15
import QtQuick.Controls 2.15
import QtQuick.Window 2.15
import MuseScore 3.0
import FileIO 3.0

MuseScore {
    id: root
    version: "1.0.0"
    title: "Scorehand"
    description: "Ask in plain language (any language) and the AI edits the open score: write melodies, scales, exercises and countermelodies, copy or clear bars, add dynamics and chord symbols, voice sections, write pads and bass lines. One Ctrl+Z undoes each request."
    categoryCode: "composing-arranging-tools"
    pluginType: "dock"
    requiresScore: true
    width: 400; height: 760

    // ---- Settings ----
    // mode "hosted": POST the exported MusicXML to the Scorehand service
    //   (customers need only this plugin + an Scorehand key; no Python, no Claude key).
    // mode "local": run copilot.py on this machine via a launcher script (developer mode).
    property string mode: "hosted"
    property string serverUrl: "https://copilot.aihud.net"   // e.g. http://127.0.0.1:8787 for local testing
    readonly property string oldFolder: "Notation" + "Copilot"   // the folder name before the rename
    property string apiKey: ""                                // your Scorehand key
    property int requestTimeoutSec: 480   // > server REQUEST_TIMEOUT 420 s and nginx 450 s, so the server's own reply arrives first

    // Local mode only -- adjust to your install.
    property string python: "python3"
    property string copilot: ""   // path to copilot.py (not distributed; hosted mode is the supported path)
    // Folder for the launcher's temp files; "" = this plugin's own folder (works on every OS).
    property string workDir: ""
    // Optional env file with ANTHROPIC_API_KEY (MuseScore's environment usually lacks it).
    property string envFile: ""
    property int sidebarWidth: 400

    // Conversation state for the request in flight.
    property string instruction: ""      // original request text
    property var history: []             // [{question, answer}] for the request in flight
    property string pendingQuestion: ""
    property string pendingKind: ""      // "clarify" | "mode" | "confirm" | ""  (mode/confirm get Apply anyway + Cancel)
    property bool busy: false
    property var job: ({})
    property int elapsed: 0
    // Live card (0.9): only what the server reports through /edit-status. No data = only the elapsed time.
    property string reqId: ""
    property var progSteps: []
    property var progBars: null          // {lo, hi, total}
    property string progTitle: ""
    property bool statusBusy: false      // one poll at a time
    property int previewRow: -1          // chat row waiting for its bar picture
    property int previewTries: 0
    // First-open example prompts: shown until the first request is sent, again after "New chat" or a score
    // switch (click fills the box, never sends). Each names bars: a bar-less request gets a "which bars?" question.
    property int sentCount: 0
    readonly property var examples: ["Add a walking bass line to bars 1-8",
                                     "Add accents to the melody in bars 1-4",
                                     "Simplify bars 1-8 for a beginner"]
    readonly property var exampleTiles: [{ title: "Add a walking bass", bars: "Bars 1\u20138", icon: "\u266a" },
                                         { title: "Add accents to the melody", bars: "Bars 1\u20134", icon: "\u266b" },
                                         { title: "Simplify for a beginner", bars: "Bars 1\u20138", icon: "\u2669" }]
    property bool hasScore: true         // false when every score was closed while this window stays open
    readonly property bool showHero: sentCount === 0 && !busy && !needActivation
    readonly property bool showExamples: showHero && hasScore && (mode !== "hosted" || apiKey !== "")
    // 402 error=activate: show the "enter your 6-digit code / resend the email" box above the input.
    property bool needActivation: false
    property bool actBusy: false
    property string planLine: ""         // 0.8.1: "Pro · 143 edits left" from the server's `account` block
    property string editsLeft: ""        // 0.9: the number alone, for the header
    property string manageUrl: ""        // signed account page (plan, usage, cancel)
    property string lastBlocked: ""      // request that hit the 402; put back in the box after activation

    // Colours: brand kit (marketing/brand/music-lab). One look: always dark, whatever MuseScore's theme is.
    // Every control sets its own colours, so nothing here may depend on the host theme.
    readonly property color cViolet: "#7c3aed"
    readonly property color cVioletDark: "#6d28d9"
    readonly property color cBg: "#0b1020"
    readonly property color cCard: "#0f172a"
    readonly property color cBorder: "#2b2f55"
    readonly property color cText: "#e2e8f0"
    readonly property color cStrong: "#ffffff"
    readonly property color cMuted: "#94a3b8"
    readonly property color cFaint: "#7c86a0"
    readonly property color cLavender: "#ddd6fe"
    readonly property color cAccent: "#a78bfa"
    readonly property color cTile: "#1a1540"
    readonly property color cTileBorder: "#3a3380"
    readonly property color cTileHover: "#2a1a6e"
    readonly property color cKbd: "#1e2640"
    readonly property color cErrorBg: "#2a1524"
    readonly property color cErrorBorder: "#7f1d3a"
    // Geist ships in the zip (fonts/, SIL OFL); the single-file .qml download simply uses the system font.
    readonly property string sysFont: Qt.application.font.family
    FontLoader { id: geistR; source: "fonts/Geist-Regular.ttf" }
    FontLoader { id: geistM; source: "fonts/Geist-Medium.ttf" }
    FontLoader { id: geistS; source: "fonts/Geist-SemiBold.ttf" }
    FontLoader { id: geistB; source: "fonts/Geist-Bold.ttf" }
    readonly property string fontRegular: geistR.status === FontLoader.Ready ? geistR.name : sysFont
    readonly property string fontMedium: geistM.status === FontLoader.Ready ? geistM.name : sysFont
    readonly property string fontSemi: geistS.status === FontLoader.Ready ? geistS.name : sysFont
    readonly property string fontBold: geistB.status === FontLoader.Ready ? geistB.name : sysFont
    readonly property string logoData: "data:image/png;base64,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"

    QProcess { id: proc }
    FileIO { id: fio }
    ListModel { id: chat }

    // ---------- sidebar placement (MS 4.7 has no docking for plugins) ----------
    Timer {
        id: placeTimer; interval: 300; repeat: true; property int tries: 0
        onTriggered: { tries++; if (placeSidebar() || tries > 10) stop() }
    }
    function placeSidebar() {
        var w = root.Window.window
        if (!w) return false
        var p = w.transientParent
        var x0, y0, ww, hh
        if (p && p.width > 0) { x0 = p.x; y0 = p.y; ww = p.width; hh = p.height }
        else { x0 = w.screen.virtualX; y0 = w.screen.virtualY
               ww = w.screen.desktopAvailableWidth; hh = w.screen.desktopAvailableHeight }
        var top = 108   // keep the menu bar + toolbars of the main window visible
        w.width = sidebarWidth
        w.height = Math.max(400, hh - top)
        w.x = x0 + ww - sidebarWidth
        w.y = y0 + top
        root.width = w.width; root.height = w.height   // content follows the window
        console.log("copilot sidebar placed at " + w.x + "," + w.y + " " + w.width + "x" + w.height
                    + (p ? " (main window " + ww + "x" + hh + ")" : " (screen)"))
        return true
    }

    // Switching to another (e.g. new) score shows the example prompts again.
    property string lastScoreName: ""
    onScoreStateChanged: {
        var n = curScore ? String(curScore.scoreName) : ""
        if (n !== lastScoreName) { if (lastScoreName !== "" && !busy) sentCount = 0; lastScoreName = n }
    }

    onRun: {
        lastScoreName = curScore ? String(curScore.scoreName) : ""
        hasScore = !!curScore
        if (mode === "hosted" && apiKey === "") loadKey()
        sayHello()
        if (mode === "hosted" && apiKey === "") askForKey()
        placeTimer.start()
    }
    // onScoreStateChanged is not reliable when the last score closes, so look at curScore directly.
    Timer { interval: 1000; repeat: true; running: true; onTriggered: hasScore = !!curScore }

    // One "plugin opened" ping per window open (and once more when a key is pasted): plugin version +
    // MuseScore version, with the key in the Authorization header (never in the URL) so the server can
    // count opens per account. No score content. Fire and forget: the reply and any error are ignored.
    function msVersion() {
        try {
            if (typeof mscoreMajorVersion !== "undefined")
                return mscoreMajorVersion + "." + mscoreMinorVersion + "." + mscoreUpdateVersion
        } catch (e) { }
        return ""
    }
    function sayHello() {
        if (mode !== "hosted") return
        try {
            var x = new XMLHttpRequest()
            x.open("POST", serverUrl.replace(/\/+$/, "") + "/v1/hello")
            x.setRequestHeader("Content-Type", "application/json")
            if (apiKey) x.setRequestHeader("Authorization", "Bearer " + apiKey)
            x.send(JSON.stringify({ v: root.version, ms: msVersion() }))
        } catch (e) { }
    }

    // ---------- Scorehand key (hosted mode) ----------
    // Either set apiKey above, or paste the key into the chat once; it is saved to scorehand-key.txt.
    // Saved next to this .qml: MuseScore 4.7 blocks plugin writes outside its allowed dirs (e.g. ~).
    // file:// URL -> local path on any OS: file:///C:/Users/x/Dokumente/a%20b.qml -> C:/Users/x/Dokumente/a b.qml,
    // file:///home/x/a.qml -> /home/x/a.qml, file://server/share/a -> //server/share/a (Windows network folder).
    function urlToPath(u) {
        var s = String(u)
        if (/^file:\/\/\//i.test(s)) s = s.substring(7)          // "/C:/..." or "/home/..."
        else if (/^file:\/\//i.test(s)) s = "//" + s.substring(7) // UNC
        else if (/^file:/i.test(s)) s = s.substring(5)
        try { s = decodeURIComponent(s) } catch (e) { }
        if (/^\/[A-Za-z]:/.test(s)) s = s.substring(1)              // Windows drive letter
        return s
    }
    // This plugin's folder (Documents/MuseScore4/Plugins/Scorehand), with a trailing "/".
    function pluginDir() { var d = urlToPath(Qt.resolvedUrl(".")); return /\/$/.test(d) ? d : d + "/" }
    // Where the hosted-mode export goes: the plugin folder; if that is not writable (probe with FileIO,
    // which fails silently -- writeScore would pop MuseScore's "retry?" dialog), the system temp folder.
    function exportPath() {
        var cands = [pluginDir()]
        try { var t = String(fio.tempPath() || "").replace(/\\/g, "/"); if (t !== "") cands.push(/\/$/.test(t) ? t : t + "/") } catch (e) { }
        for (var i = 0; i < cands.length; i++) {
            fio.source = cands[i] + "copilot-export.musicxml"
            if (fio.write("")) return fio.source
        }
        return cands[0] + "copilot-export.musicxml"
    }
    function keyPath() { return pluginDir() + "scorehand-key.txt" }
    // Keys saved by the plugin under its old name are still read: copilot-key.txt in this folder (old zip unpacked over a
    // renamed folder) or in the old NotationCopilot folder next to this one. A key found there is copied to keyPath().
    function loadKey() {
        var cands = [keyPath(), pluginDir() + "copilot-key.txt", pluginDir() + "../" + oldFolder + "/copilot-key.txt"]
        for (var i = 0; i < cands.length; i++) {
            fio.source = cands[i]
            if (!fio.exists()) continue
            var k = String(fio.read()).trim()
            if (!/^nc_live_[A-Za-z0-9_-]{8,}$/.test(k)) continue
            apiKey = k
            if (i > 0) { fio.source = keyPath(); fio.write(k) }
            return
        }
    }
    function askForKey() {
        say("bot", "Welcome to Scorehand! To start, paste your Scorehand key (it starts with nc_live_) "
            + "here and press Enter.\n\nNo key yet? Get a free one (100-edit trial, then 10 a month) at https://scorehand.aihud.net", "", "")
    }

    // ---------- UI (AiHud Music Lab look; always dark) ----------
    component Txt: Text {
        font.family: fontRegular; font.pixelSize: 13; color: cText; textFormat: Text.PlainText
    }
    component Btn: Rectangle {      // text button; primary = filled violet
        id: btn
        property string text: ""
        property bool primary: false
        signal clicked()
        implicitWidth: btnLabel.implicitWidth + 24; implicitHeight: 30; radius: 9
        opacity: enabled ? 1 : 0.45
        color: primary ? (btnMouse.containsMouse ? cVioletDark : cViolet)
                       : (btnMouse.containsMouse ? cTile : "transparent")
        border.color: primary ? "transparent" : cTileBorder
        Txt { id: btnLabel; anchors.centerIn: parent; text: btn.text; font.pixelSize: 12; font.family: fontMedium
              font.weight: Font.Medium; color: btn.primary ? "#ffffff" : cLavender }
        MouseArea { id: btnMouse; anchors.fill: parent; hoverEnabled: true; enabled: btn.enabled
                    cursorShape: Qt.PointingHandCursor; onClicked: btn.clicked() }
    }
    component BrandGradient: Canvas {     // the brand 135deg gradient (no Qt5/Qt6-specific effects module)
        onWidthChanged: requestPaint()
        onHeightChanged: requestPaint()
        onPaint: {
            var ctx = getContext("2d"), g = ctx.createLinearGradient(0, 0, width, Math.max(height, width * 0.35))
            g.addColorStop(0, "#0b1020"); g.addColorStop(0.55, "#2a1a6e"); g.addColorStop(1, "#6d28d9")
            ctx.fillStyle = g; ctx.fillRect(0, 0, width, height)
        }
    }

    Rectangle {
        anchors.fill: parent; color: cBg

        Item {   // header: brand on the left; edits left, New chat, Close on the right
            id: header; anchors { left: parent.left; right: parent.right; top: parent.top }
            height: 66
            BrandGradient { anchors.fill: parent }
            Image { id: logo; x: 14; anchors.verticalCenter: parent.verticalCenter; width: 36; height: 36
                    source: logoData; smooth: true; mipmap: true }
            Column {
                anchors { left: logo.right; leftMargin: 10; verticalCenter: parent.verticalCenter
                          right: headerRight.left; rightMargin: 8 }
                Txt { width: parent.width; elide: Text.ElideRight; text: "Scorehand"; font.family: fontBold
                      font.bold: true; font.pixelSize: 14; color: "#ffffff" }
                Txt { width: parent.width; elide: Text.ElideRight; text: "Your score, in plain words"; font.family: fontMedium
                      font.weight: Font.Medium; font.pixelSize: 11; color: "#a78bfa" }
            }
            Row {
                id: headerRight; spacing: 6
                anchors { right: parent.right; rightMargin: 12; verticalCenter: parent.verticalCenter }
                Item {   // plan + edits left (server `account` block); click = account page
                    id: planBox; visible: planLine !== ""; height: 34; anchors.verticalCenter: parent.verticalCenter
                    width: Math.max(planNum.implicitWidth, planLbl.implicitWidth) + 6
                    Column {
                        anchors { right: parent.right; verticalCenter: parent.verticalCenter }
                        Txt { id: planNum; anchors.right: parent.right; visible: editsLeft !== ""; text: editsLeft
                              font.family: fontBold; font.bold: true; font.pixelSize: 14; color: "#ffffff" }
                        Txt { id: planLbl; anchors.right: parent.right
                              text: editsLeft !== "" ? "edits left" : planLine; font.pixelSize: 10; color: "#ddd6fe"
                              font.underline: manageUrl !== "" && planMouse.containsMouse }
                    }
                    MouseArea { id: planMouse; anchors.fill: parent; hoverEnabled: true
                                cursorShape: manageUrl !== "" ? Qt.PointingHandCursor : Qt.ArrowCursor
                                onClicked: if (manageUrl !== "") Qt.openUrlExternally(manageUrl) }
                    ToolTip.visible: planMouse.containsMouse; ToolTip.delay: 400; ToolTip.text: planLine
                }
                Repeater {
                    model: [{ g: "+", tip: "New chat", act: "new" }, { g: "×", tip: "Close", act: "close" }]
                    delegate: Rectangle {
                        width: 28; height: 28; radius: 8; anchors.verticalCenter: parent.verticalCenter
                        color: iconMouse.containsMouse ? "#40ffffff" : "#1fffffff"
                        opacity: modelData.act === "new" && busy ? 0.45 : 1
                        Txt { anchors.centerIn: parent; text: modelData.g; color: "#ffffff"; font.pixelSize: 17 }
                        MouseArea { id: iconMouse; anchors.fill: parent; hoverEnabled: true; cursorShape: Qt.PointingHandCursor
                                    onClicked: modelData.act === "close" ? root.quit() : newChat() }
                        ToolTip.visible: iconMouse.containsMouse; ToolTip.delay: 400; ToolTip.text: modelData.tip
                    }
                }
            }
        }

        Item {   // first open
            id: hero; visible: showHero; height: visible ? heroCol.height + 40 : 0
            anchors { left: parent.left; right: parent.right; top: header.bottom }
            BrandGradient { anchors.fill: parent }
            Column {
                id: heroCol; x: 16; y: 22; width: parent.width - 32; spacing: 7
                Column {
                    width: parent.width
                    Txt { text: "Your score,"; font.family: fontBold; font.bold: true; font.pixelSize: 24; color: "#ffffff" }
                    Txt { text: "in plain words."; font.family: fontBold; font.bold: true; font.pixelSize: 24; color: "#a78bfa" }
                }
                Txt { width: parent.width; wrapMode: Text.Wrap; font.pixelSize: 13; color: "#ddd6fe"; lineHeight: 1.15
                      text: "Sheet music tools that do the tedious part. Say what you want, and it lands in the open score." }
            }
        }

        ListView {
            id: list
            anchors { left: parent.left; right: parent.right; top: hero.visible ? hero.bottom : header.bottom
                      bottom: showExamples ? examplesBox.top : (needActivation ? actBox.top : (noScoreBox.visible ? noScoreBox.top : composer.top))
                      leftMargin: 12; rightMargin: 12; topMargin: 12; bottomMargin: 10 }
            clip: true; spacing: 11; model: chat
            ScrollBar.vertical: ScrollBar {}
            onCountChanged: Qt.callLater(function() { list.positionViewAtEnd() })
            Gradient { id: barOn; GradientStop { position: 0; color: "#a78bfa" } GradientStop { position: 1; color: "#6d28d9" } }
            footer: Item {
                width: list.width; height: busy ? workCard.height + 11 : 0; visible: busy
                onHeightChanged: Qt.callLater(function() { list.positionViewAtEnd() })
                Rectangle {
                    id: workCard; y: 11; width: parent.width - 8; height: workCol.height + 22
                    radius: 14; color: cCard; border.color: cBorder
                    Column {
                        id: workCol; x: 12; y: 11; width: parent.width - 24; spacing: 8
                        Item {
                            width: parent.width; height: 18
                            Txt { anchors { left: parent.left; right: workTime.left; rightMargin: 6; verticalCenter: parent.verticalCenter }
                                  elide: Text.ElideRight; text: progTitle !== "" ? progTitle : "Working on your score"
                                  font.family: fontSemi; font.weight: Font.DemiBold; color: cStrong }
                            Txt { id: workTime; anchors { right: parent.right; verticalCenter: parent.verticalCenter }
                                  text: Math.floor(elapsed / 60) + ":" + ("0" + elapsed % 60).slice(-2)
                                  font.pixelSize: 11; font.family: fontMedium; font.weight: Font.Medium; color: cAccent }
                        }
                        Column {   // bar map: the bars being edited, as the server reports them
                            width: parent.width; spacing: 3; visible: progBars !== null
                            Row {
                                id: barMap; width: parent.width; height: 34; spacing: 3
                                property int cells: progBars ? Math.min(progBars.total, 32) : 0
                                Repeater {
                                    model: barMap.cells
                                    delegate: Rectangle {
                                        property bool on: {
                                            if (!progBars) return false
                                            var a = 1 + index * progBars.total / barMap.cells, b = 1 + (index + 1) * progBars.total / barMap.cells
                                            return a < progBars.hi + 1 && b > progBars.lo
                                        }
                                        width: (barMap.width - (barMap.cells - 1) * 3) / barMap.cells; height: 34; radius: 3
                                        color: "#1a2138"
                                        gradient: on ? barOn : null
                                    }
                                }
                            }
                            Txt { font.pixelSize: 11; color: cMuted
                                  text: !progBars ? "" : (progBars.lo === progBars.hi ? "Bar " + progBars.lo
                                        : "Bars " + progBars.lo + "\u2013" + progBars.hi) + " of " + progBars.total }
                        }
                        Repeater {   // the real stages of this request
                            model: progSteps
                            delegate: Item {
                                width: workCol.width; height: Math.max(stepText.height, 16) + 4
                                Item {
                                    id: stepIcon; width: 15; height: 15; anchors.verticalCenter: parent.verticalCenter
                                    Txt { anchors.centerIn: parent; visible: modelData.state === "done"; text: "\u2713"; color: cAccent; font.pixelSize: 12 }
                                    Rectangle { anchors.centerIn: parent; visible: modelData.state === "pending"; width: 8; height: 8; radius: 4
                                                color: "transparent"; border.color: cFaint }
                                    Canvas {
                                        anchors.fill: parent; visible: modelData.state === "active"
                                        onPaint: { var c = getContext("2d"); c.reset(); c.strokeStyle = String(cAccent); c.lineWidth = 2
                                                   c.beginPath(); c.arc(7.5, 7.5, 6, 0, Math.PI * 1.5); c.stroke() }
                                        RotationAnimator on rotation { from: 0; to: 360; duration: 900; loops: Animation.Infinite
                                                                       running: modelData.state === "active" }
                                    }
                                }
                                Txt { id: stepText; anchors { left: stepIcon.right; leftMargin: 9; right: parent.right; verticalCenter: parent.verticalCenter }
                                      text: modelData.label; wrapMode: Text.Wrap; font.pixelSize: 13
                                      font.family: modelData.state === "active" ? fontSemi : fontRegular
                                      font.weight: modelData.state === "active" ? Font.DemiBold : Font.Normal
                                      color: modelData.state === "active" ? cStrong : (modelData.state === "done" ? cMuted : cFaint) }
                            }
                        }
                    }
                }
            }
            delegate: Item {
                id: row
                width: list.width
                height: bubble.height
                property bool mine: model.role === "user"
                property bool isStatus: model.role === "status"
                property bool isResult: model.title !== "" && model.undoHint
                property bool showLog: false
                property var opts: model.opts === "" ? [] : model.opts.split("\n")
                // A "Give bar numbers, e.g. ..." entry is typing guidance, not a real choice (it fills
                // the input box when tapped, it never answers the question by itself): keep it out of
                // the tile grid and show it as plain hint text instead.
                property string hintOpt: { var h = opts.filter(function(o) { return /e\.g\./.test(o) }); return h.length ? h[0] : "" }
                property var tileOpts: opts.filter(function(o) { return !/e\.g\./.test(o) })
                property var chips: model.chips === "" ? [] : JSON.parse(model.chips)
                property bool twoCol: tileOpts.length > 1 && tileOpts.length <= 6 && tileOpts.every(function(o) { return optParts(o).title.length <= 20 })
                Rectangle {
                    id: bubble
                    width: mine ? Math.min(list.width * 0.86, body.implicitWidth + 24) : list.width - 8
                    height: col.height + (mine ? 15 : 22)
                    anchors.right: mine ? parent.right : undefined
                    radius: mine ? 13 : 14
                    color: mine ? cViolet : (isStatus ? "transparent" : (model.role === "error" ? cErrorBg
                           : (model.role === "limit" ? cTile : cCard)))
                    border.color: mine || isStatus ? "transparent" : (model.role === "error" ? cErrorBorder
                                  : (model.role === "limit" ? cViolet : cBorder))
                    Column {
                        id: col; x: 12; y: mine ? 7 : 11; width: bubble.width - 24; spacing: 8
                        Item {   // card title + small badge ("32 notes")
                            width: parent.width; height: Math.max(cardTitle.height, 16); visible: model.title !== ""
                            Txt { id: cardTitle; anchors { left: parent.left; right: badge.left; rightMargin: 6 }
                                  text: model.title; wrapMode: Text.Wrap; font.family: fontSemi
                                  font.weight: Font.DemiBold; color: cStrong }
                            Txt { id: badge; anchors.right: parent.right; text: model.badge; font.pixelSize: 11
                                  font.family: fontMedium; font.weight: Font.Medium; color: cAccent }
                        }
                        Txt { id: body; width: parent.width; visible: text !== ""; text: model.text; wrapMode: Text.Wrap
                              font.italic: isStatus; font.family: mine ? fontMedium : fontRegular
                              font.weight: mine ? Font.Medium : Font.Normal
                              font.pixelSize: isResult ? 12 : 13
                              color: mine ? "#ffffff" : (isStatus || isResult ? cMuted : cText) }
                        Rectangle {   // the edited bars (server-rendered; absent if rendering failed or was slow)
                            visible: model.preview !== ""; width: parent.width; color: "#ffffff"; radius: 10; clip: true
                            border.color: "transparent"
                            height: visible ? Math.min(180, Math.max(40, prevImg.implicitWidth > 0
                                    ? (width - 8) * prevImg.implicitHeight / prevImg.implicitWidth + 8 : 60)) : 0
                            Image { id: prevImg; anchors.fill: parent; anchors.margins: 4; source: model.preview
                                    fillMode: Image.PreserveAspectFit; smooth: true; mipmap: true
                                    onStatusChanged: if (status === Image.Ready) scrollDown.restart() }
                        }
                        Txt { visible: model.caption !== ""; text: model.caption; font.pixelSize: 10; color: cMuted }
                        Grid {   // question options as one-tap tiles (the typing hint, if any, is plain text below)
                            id: optGrid; width: parent.width; columns: row.twoCol ? 2 : 1; spacing: 6; visible: row.tileOpts.length > 0
                            Repeater {
                                model: row.tileOpts
                                delegate: Rectangle {
                                    id: optTile
                                    property var parts: optParts(modelData)
                                    property bool live: row.isLive() && !busy
                                    width: row.twoCol ? (optGrid.width - 6) / 2 : optGrid.width
                                    height: optCol.height + 14; radius: 10; opacity: live ? 1 : 0.55
                                    color: optMouse.containsMouse && live ? cTileHover : cTile; border.color: cTileBorder
                                    Column {
                                        id: optCol; x: 10; y: 7; width: parent.width - 20
                                        Txt { width: parent.width; text: optTile.parts.title; wrapMode: Text.Wrap; font.pixelSize: 12
                                              font.family: fontSemi; font.weight: Font.DemiBold; color: cStrong }
                                        Txt { width: parent.width; visible: text !== ""; text: optTile.parts.sub; wrapMode: Text.Wrap
                                              font.pixelSize: 11; color: cAccent }
                                    }
                                    MouseArea { id: optMouse; anchors.fill: parent; hoverEnabled: true; enabled: optTile.live
                                                cursorShape: Qt.PointingHandCursor; onClicked: pickOption(modelData) }
                                }
                            }
                        }
                        Txt {   // typing hint (e.g. "Give bar numbers, e.g. \"bars 9-16\""): guidance, not a tappable choice
                            visible: row.hintOpt !== ""; width: parent.width; text: row.hintOpt
                            wrapMode: Text.Wrap; font.pixelSize: 11; font.italic: true; color: cMuted
                        }
                        Flow {   // follow-up suggestions: fill the box, never send
                            width: parent.width; spacing: 6; visible: row.chips.length > 0
                            Repeater {
                                model: row.chips
                                delegate: Btn { text: modelData.label; radius: 15; height: 28; onClicked: useExample(modelData.text) }
                            }
                        }
                        Txt { visible: !isResult && model.detail !== ""; width: body.width; text: model.detail
                              wrapMode: Text.Wrap; font.pixelSize: 10; color: cMuted }
                        Item {   // Ctrl Z hint; the debug line stays, small, with the log behind "Details"
                            width: parent.width; height: 18; visible: isResult
                            Row {
                                spacing: 4; anchors.verticalCenter: parent.verticalCenter
                                Repeater {
                                    model: [Qt.platform.os === "osx" ? "Cmd" : "Ctrl", "Z"]
                                    delegate: Rectangle {
                                        width: kbdText.implicitWidth + 10; height: 16; radius: 4; color: cKbd
                                        Txt { id: kbdText; anchors.centerIn: parent; text: modelData; font.pixelSize: 10; color: cText }
                                    }
                                }
                                Txt { anchors.verticalCenter: parent.verticalCenter; text: " undoes the whole edit"; font.pixelSize: 11; color: cMuted }
                            }
                            Txt {
                                anchors { right: parent.right; verticalCenter: parent.verticalCenter }
                                text: model.cost + (model.detail !== "" ? (model.cost !== "" ? "  " : "") + (row.showLog ? "Hide" : "Details") : "")
                                font.pixelSize: 10; color: cFaint
                                MouseArea { anchors.fill: parent; enabled: model.detail !== ""; cursorShape: Qt.PointingHandCursor
                                            onClicked: row.showLog = !row.showLog }
                            }
                        }
                        Txt { visible: isResult && row.showLog; width: parent.width; text: model.detail
                              wrapMode: Text.Wrap; font.pixelSize: 10; color: cMuted }
                        Btn {   // 402 / near the limit: open the plans page in the browser
                            visible: model.url !== ""; text: "Upgrade / buy edits"; primary: true
                            onClicked: Qt.openUrlExternally(model.url)
                        }
                        Row {
                            spacing: 6; visible: model.kind !== "" && row.isLive()
                            Btn { text: "Apply anyway"; primary: true; enabled: !busy
                                  visible: model.kind === "mode" || model.kind === "confirm"; onClicked: forceApply() }
                            Btn { text: "Skip this question"; enabled: !busy; onClicked: skipQuestion() }
                        }
                    }
                }
                function isLive() { return model.live && pendingKind !== "" }
            }
        }

        Column {   // first-open example tiles: click fills the box, never sends
            id: examplesBox
            visible: showExamples
            anchors { left: parent.left; right: parent.right; bottom: composer.top
                      leftMargin: 12; rightMargin: 12; bottomMargin: 10 }
            spacing: 9
            Txt { text: "Try one on this score"; font.pixelSize: 12; font.family: fontMedium; font.weight: Font.Medium; color: cAccent }
            Repeater {
                model: examples
                delegate: Rectangle {
                    width: examplesBox.width; height: 50; radius: 14
                    property var tile: exampleTiles[index]
                    color: tileMouse.containsMouse ? cTile : cCard; border.color: tileMouse.containsMouse ? cViolet : cBorder
                    Rectangle {
                        id: tileIcon; x: 11; anchors.verticalCenter: parent.verticalCenter; width: 32; height: 32; radius: 9
                        color: "#2a1a6e"
                        Txt { anchors.centerIn: parent; text: tile.icon; font.pixelSize: 16; color: cAccent }
                    }
                    Column {
                        anchors { left: tileIcon.right; leftMargin: 11; right: tileArrow.left; rightMargin: 6
                                  verticalCenter: parent.verticalCenter }
                        Txt { width: parent.width; elide: Text.ElideRight; text: tile.title; font.family: fontSemi
                              font.weight: Font.DemiBold; color: cStrong }
                        Txt { width: parent.width; text: tile.bars; font.pixelSize: 11; color: cMuted }
                    }
                    Txt { id: tileArrow; anchors { right: parent.right; rightMargin: 13; verticalCenter: parent.verticalCenter }
                          text: "\u2192"; color: cAccent }
                    MouseArea { id: tileMouse; anchors.fill: parent; hoverEnabled: true; cursorShape: Qt.PointingHandCursor
                                onClicked: useExample(modelData) }
                }
            }
        }

        Rectangle {   // every score was closed while the window stays open
            id: noScoreBox
            visible: !hasScore && !needActivation
            anchors { left: parent.left; right: parent.right; bottom: composer.top
                      leftMargin: 12; rightMargin: 12; bottomMargin: 10 }
            height: noScoreText.height + 22; radius: 14; color: cCard; border.color: cBorder
            Txt { id: noScoreText; x: 12; y: 11; width: parent.width - 24; wrapMode: Text.Wrap; color: cMuted
                  text: "No score is open. Open one in MuseScore and I can work on it here." }
        }

        Rectangle {   // activation: 6-digit code from the email, or resend the email (402 error=activate)
            id: actBox
            visible: needActivation
            anchors { left: parent.left; right: parent.right; bottom: composer.top
                      leftMargin: 12; rightMargin: 12; bottomMargin: 10 }
            height: actCol.height + 22; radius: 14; color: cCard; border.color: cViolet
            Column {
                id: actCol; x: 12; y: 11; width: parent.width - 24; spacing: 8
                Txt { width: parent.width; wrapMode: Text.Wrap; font.family: fontSemi; font.weight: Font.DemiBold; color: cStrong
                      text: "Activate your free edits: type the 6-digit code from the email we sent you." }
                Row {
                    spacing: 6
                    TextField {
                        id: codeInput; width: 120; height: 34; placeholderText: "123456"; enabled: !actBusy
                        maximumLength: 7; inputMethodHints: Qt.ImhDigitsOnly; font.pixelSize: 15; font.family: fontRegular
                        color: cText; placeholderTextColor: cFaint; selectByMouse: true
                        background: Rectangle { radius: 9; color: cBg
                                                border.color: codeInput.activeFocus ? cViolet : cBorder }
                        onAccepted: submitCode()
                    }
                    Btn { text: "Activate"; primary: true; height: 34; onClicked: submitCode()
                          enabled: !actBusy && codeInput.text.replace(/\D/g, "").length === 6 }
                }
                Btn { text: "Resend activation email"; enabled: !actBusy; onClicked: resendActivation() }
            }
        }

        Rectangle {   // composer
            id: composer
            anchors { left: parent.left; right: parent.right; bottom: parent.bottom
                      leftMargin: 12; rightMargin: 12; bottomMargin: 12 }
            height: inputScroll.height + 18; radius: 14; color: cCard
            border.color: input.activeFocus ? cViolet : cBorder
            Rectangle {   // soft glow around the box while typing
                anchors.fill: parent; anchors.margins: -3; radius: 17; color: "transparent"; z: -1
                border.color: cViolet; border.width: 3; opacity: input.activeFocus ? 0.22 : 0
            }
            ScrollView {
                id: inputScroll
                anchors { left: parent.left; right: sendBtn.left; top: parent.top; leftMargin: 8; rightMargin: 4; topMargin: 9 }
                height: Math.min(Math.max(input.implicitHeight, 30), 120)
                TextArea {
                    id: input
                    wrapMode: TextEdit.Wrap; font.pixelSize: 13; font.family: fontRegular; enabled: !busy
                    color: cText; placeholderTextColor: cFaint; selectByMouse: true; padding: 5
                    background: null
                    placeholderText: isQuestionPending() ? "Answer the question, or tap an option above"
                                   : (showHero ? "What should we write?" : "Tell me what to write or change")
                    Keys.onPressed: function(e) {
                        if ((e.key === Qt.Key_Return || e.key === Qt.Key_Enter) && !(e.modifiers & Qt.ShiftModifier)) {
                            e.accepted = true; send()
                        }
                    }
                }
            }
            Rectangle {
                id: sendBtn; width: 30; height: 30; radius: 10
                anchors { right: parent.right; rightMargin: 9; bottom: parent.bottom; bottomMargin: 9 }
                property bool canSend: !busy && input.text.trim() !== ""
                color: sendMouse.containsMouse && canSend ? cVioletDark : cViolet; opacity: canSend ? 1 : 0.5
                Txt { anchors.centerIn: parent; text: "↑"; color: "#ffffff"; font.pixelSize: 15; font.bold: true }
                MouseArea { id: sendMouse; anchors.fill: parent; hoverEnabled: true; enabled: sendBtn.canSend
                            cursorShape: Qt.PointingHandCursor; onClicked: send() }
                ToolTip.visible: sendMouse.containsMouse; ToolTip.delay: 600
                ToolTip.text: isQuestionPending() ? "Answer (Enter)" : "Send (Enter)"
            }
        }
    }

    // ---------- conversation logic ----------
    function updatePlan(a) {
        var name = a.plan_name || ""
        if (a.edits_left !== undefined && a.edits_left !== null && a.limit)
            planLine = name + " \u00b7 " + a.edits_left + " of " + a.limit + " edits left"
        else
            planLine = name
        editsLeft = (a.edits_left !== undefined && a.edits_left !== null && a.limit) ? String(a.edits_left) : ""
        manageUrl = (a.manage_url && /^https:\/\//.test(a.manage_url)) ? a.manage_url : ""
    }

    // card (optional): { title, badge, cost, caption, chips (JSON), undoHint }
    function say(role, text, kind, opts, detail, url, card) {
        var c = card || {}
        for (var i = 0; i < chat.count; i++) chat.setProperty(i, "live", false)
        chat.append({ role: role, text: text, kind: kind || "", opts: opts || "", detail: detail || "",
                      live: (kind || "") !== "", url: url || "", title: c.title || "", badge: c.badge || "",
                      cost: c.cost || "", preview: "", caption: "", chips: c.chips || "", undoHint: !!c.undoHint })
    }
    // "Bars 1-8 - Over the new bass" / "Bars 1-8 (over the new bass)" -> tile with a title and a small line.
    function optParts(o) {
        var m = /^(.+?)\s+[\u2014\u2013-]\s+(.+)$/.exec(o) || /^(.+?)\s*\((.+)\)$/.exec(o)
        return m ? { title: m[1], sub: m[2] } : { title: o, sub: "" }
    }
    // Example tile / follow-up chip: fill the box (user may change the bar numbers), focus it, cursor at the end. Never sends.
    function useExample(t) {
        input.text = t
        input.forceActiveFocus()
        input.cursorPosition = input.text.length
    }
    function newChat() {
        if (busy) return
        chat.clear(); resetRequest(); sentCount = 0      // back to the first-open screen
    }
    function resetRequest() { instruction = ""; history = []; pendingQuestion = ""; pendingKind = "" }
    function addAnswer(a) { var h = history.slice(); h.push({ question: pendingQuestion, answer: a }); history = h }
    function historyArgs() {
        var s = ""
        for (var i = 0; i < history.length; i++)
            s += " --question " + shq(history[i].question) + " --answer " + shq(history[i].answer)
        return s
    }
    function shq(s) { return "'" + String(s).replace(/'/g, "'\\''") + "'" }

    function send() {
        var t = input.text.trim()
        if (t === "" || busy) return
        input.text = ""
        if (/^nc_live_[A-Za-z0-9_-]{8,}$/.test(t)) {      // the user pasted their key
            apiKey = t
            fio.source = keyPath()
            var saved = fio.write(t)
            sayHello()
            say("user", t.substring(0, 12) + "...", "", "")
            say("bot", "Key " + (saved ? "saved" : "set for this session") + ". Now tell me what to change in this score, "
                + "e.g. \"write a sustained string pad under bars 9-16\".", "", "")
            return
        }
        if (mode === "hosted" && apiKey === "") { say("user", t, "", ""); askForKey(); return }
        if (!curScore) { input.text = t; say("error", "Open a score first.", "", ""); return }
        say("user", t, "", "")
        if (needActivation && /^\d{3} ?\d{3}$/.test(t)) { codeInput.text = t; submitCode(); return }
        sentCount++
        if (isQuestionPending()) {
            addAnswer(t)
            runCopilot(false)
        } else {
            resetRequest(); instruction = t; runCopilot(false)
        }
    }
    // "clarify" (free-text planner question) and "mode" (replace-or-voice-2) both take a typed or
    // tapped answer; "confirm" (plan-is-large) does not -- Apply anyway/Cancel are its only answers.
    function isQuestionPending() { return pendingKind === "clarify" || pendingKind === "mode" }
    function pickOption(o) {
        if (/e\.g\./.test(o)) {           // template option: let the user fill it in
            var m = /"([^"]+)"/.exec(o)
            input.text = m ? m[1] : ""; input.forceActiveFocus(); input.cursorPosition = input.text.length
            return
        }
        say("user", o, "", "")
        addAnswer(o)
        runCopilot(false)
    }
    // Drops the pending question without calling the server; the next text typed is a new request.
    function skipQuestion() {
        resetRequest()
        say("status", "Question skipped. Tell me what you'd like next.", "", "")
        input.forceActiveFocus()
    }
    function forceApply() {
        say("user", "Apply anyway", "", "")
        if (pendingKind === "mode")
            addAnswer("No more detail; use your best judgement.")
        runCopilot(true)
    }

    function runCopilot(force) {
        if (!curScore) { say("error", "Open a score first.", "", ""); return }
        var target = curScore.scoreName
        if (mode === "hosted") {
            // One fixed file (plugin folder, else system temp; see exportPath), overwritten each
            // request and deleted after upload. No hard-coded Unix paths, no shell commands.
            var src = exportPath()
            // always export the OPEN score: follow-ups see earlier edits and manual changes
            if (!writeScore(curScore, src, "musicxml")) {
                say("error", "Could not export the score. I tried to save a temporary copy here:\n" + src
                    + "\n\nPlease check that this folder exists and that you are allowed to write to it. "
                    + "If it keeps happening, reinstall the plugin into your Documents\\MuseScore4\\Plugins folder "
                    + "(the Scorehand folder goes inside Plugins) and restart MuseScore.", "", "")
                return
            }
            postHosted(src, "", force, target); return
        }
        // ---- local (developer) mode, Linux/macOS ----
        var stamp = Date.now()
        var wd = workDir !== "" ? workDir.replace(/\/+$/, "") + "/" : pluginDir()
        if (workDir !== "") { proc.startWithArgs("mkdir", ["-p", wd]); proc.waitForFinished(5000) }
        src = wd + "in-" + stamp + ".musicxml"
        var dst = wd + "out-" + stamp + ".musicxml"
        var rep = wd + "report-" + stamp + ".json"
        var done = wd + "done-" + stamp
        if (!writeScore(curScore, src, "musicxml")) {
            say("error", "Could not export the score to " + src + ".", "", ""); return
        }
        var sh = wd + "run-" + stamp + ".sh"
        fio.source = sh
        fio.write("[ -f " + shq(envFile) + " ] && { set -a; . " + shq(envFile) + "; set +a; }\n"
                  + shq(python) + " " + shq(copilot) + " " + shq(src) + " " + shq(instruction)
                  + historyArgs() + (force ? " --yes" : "") + " -o " + shq(dst) + " > " + shq(rep) + " 2>&1\n"
                  + "echo $? > " + shq(done) + "\n")
        console.log("copilot launcher: " + sh)
        job = { rep: rep, dst: dst, done: done, hosted: false, target: target }
        busy = true; elapsed = 0
        proc.startWithArgs("sh", [sh])
        poll.start()
    }

    // ---------- activation (hosted mode) ----------
    function actPost(path, body, done) {
        actBusy = true
        var x = new XMLHttpRequest()
        x.onreadystatechange = function() {
            if (x.readyState !== XMLHttpRequest.DONE) return
            actBusy = false
            var r = null
            try { r = JSON.parse(x.responseText) } catch (e) { r = null }
            done(x.status, r || {})
        }
        x.open("POST", serverUrl.replace(/\/+$/, "") + path)
        x.setRequestHeader("Content-Type", "application/json")
        x.send(JSON.stringify(body))
    }
    function submitCode() {
        var c = codeInput.text.replace(/\D/g, "")
        if (c.length !== 6 || actBusy) return
        actPost("/v1/activate", { key: apiKey, code: c }, function(st, r) {
            if (st === 0) { say("error", "Could not reach the Scorehand service at " + serverUrl + ".", "", ""); return }
            if (r.ok) {
                needActivation = false; codeInput.text = ""
                say("bot", r.message || "Activated.", "", "")
                if (lastBlocked !== "" && input.text === "") { input.text = lastBlocked; input.forceActiveFocus() }
                lastBlocked = ""
            } else say("error", r.message || ("Activation failed (HTTP " + st + ")."), "", "")
        })
    }
    function resendActivation() {
        if (actBusy) return
        actPost("/v1/resend-activation", { key: apiKey }, function(st, r) {
            if (st === 0) { say("error", "Could not reach the Scorehand service at " + serverUrl + ".", "", ""); return }
            if (r.result === "already") needActivation = false
            say(r.ok ? "bot" : "error", r.message || ("Could not resend (HTTP " + st + ")."), "", "")
        })
    }

    Timer {
        id: poll; interval: 1000; repeat: true
        onTriggered: {
            elapsed++
            if (job.hosted) {
                if (elapsed > requestTimeoutSec && job.xhr) {
                    var x = job.xhr; job.xhr = null; x.abort(); stop(); busy = false
                    statusTimer.stop()
                    say("error", "The Scorehand service did not answer within " + requestTimeoutSec + "s.", "", "")
                    resetRequest()
                }
                return
            }
            fio.source = job.done
            if (!fio.exists()) {
                if (elapsed > 300) { stop(); busy = false; say("error", "Scorehand timed out.", "", "") }
                return
            }
            stop(); busy = false
            var rc = parseInt(fio.read())
            fio.source = job.rep
            handleReport(fio.read(), rc)
        }
    }

    // ---------- hosted mode ----------
    function postHosted(src, dst, force, target) {
        if (apiKey === "") { askForKey(); return }
        fio.source = src
        var xml = fio.read()
        try { fio.remove() } catch (e) { }                  // don't leave score copies lying around
        if (!xml || xml.length < 50) { say("error", "Could not read the exported score.", "", ""); return }
        xml = String(xml).replace(/>\n[ \t]*</g, "><")     // drop indentation: ~30% smaller upload
        var xhr = new XMLHttpRequest()
        job = { dst: dst, hosted: true, xhr: xhr, target: target }
        busy = true; elapsed = 0; poll.start()
        startStatus()
        xhr.onreadystatechange = function() {
            if (xhr.readyState !== XMLHttpRequest.DONE || job.xhr !== xhr) return
            job.xhr = null; poll.stop(); busy = false
            statusTimer.stop()
            handleHosted(xhr.status, xhr.responseText)
        }
        xhr.open("POST", serverUrl.replace(/\/+$/, "") + "/v1/edit")
        xhr.setRequestHeader("Content-Type", "application/json")
        xhr.setRequestHeader("Authorization", "Bearer " + apiKey)
        xhr.setRequestHeader("X-Copilot-Request-Id", reqId)
        xhr.send(JSON.stringify({ musicxml: xml, instruction: instruction, history: history, yes: !!force,
                                  inplace: true, plugin: root.version }))
        console.log("copilot hosted request -> " + serverUrl + " (" + xml.length + " bytes)")
    }

    // ---- live stages + bar picture: GET /edit-status/<id>. Any failure just means nothing new to show. ----
    function startStatus() {
        reqId = Date.now().toString(36) + "-" + Math.floor(Math.random() * 1e9).toString(36)
        progSteps = []; progBars = null; progTitle = ""; previewRow = -1
        statusTimer.restart()
    }
    function pollStatus() {
        if (statusBusy || reqId === "") return
        statusBusy = true
        var x = new XMLHttpRequest()
        x.onreadystatechange = function() {
            if (x.readyState !== XMLHttpRequest.DONE) return
            statusBusy = false
            var r = null
            try { r = JSON.parse(x.responseText) } catch (e) { r = null }
            if (x.status !== 200 || !r || !r.ok) { if (previewRow >= 0) previewWait(); return }
            if (previewRow >= 0) {
                var p = r.preview || {}
                if (p.state === "ready" && previewRow < chat.count) {
                    chat.setProperty(previewRow, "preview", String(p.image || ""))
                    chat.setProperty(previewRow, "caption", String(p.caption || ""))
                    previewRow = -1; statusTimer.stop()
                    Qt.callLater(function() { list.positionViewAtEnd() })
                } else if (p.state === "pending") previewWait()
                else { previewRow = -1; statusTimer.stop() }
            } else if (busy) {
                progSteps = r.steps || []; progBars = r.bars || null; progTitle = r.title || ""
            }
        }
        x.open("GET", serverUrl.replace(/\/+$/, "") + "/edit-status/" + reqId)
        x.setRequestHeader("Authorization", "Bearer " + apiKey)
        x.send()
    }
    function previewWait() { if (++previewTries > 12) { previewRow = -1; statusTimer.stop() } }   // about 18 s, then no picture
    function waitForPreview(row) { previewRow = row; previewTries = 0; statusTimer.restart() }
    Timer { id: scrollDown; interval: 150; onTriggered: list.positionViewAtEnd() }   // after the card has its new height
    Timer { id: statusTimer; interval: 1500; repeat: true; onTriggered: pollStatus() }

    function handleHosted(httpStatus, txt) {
        var r = null
        try { r = JSON.parse(txt) } catch (e) { r = null }
        if (!r) {
            say("error", httpStatus === 0 ? "Could not reach the Scorehand service at " + serverUrl + "."
                       : httpStatus === 413 ? "This score is too large for the Scorehand service."
                                            : "Unexpected reply from the Scorehand service (HTTP " + httpStatus + ").",
                "", "", String(txt || "").slice(0, 800))
            resetRequest(); return
        }
        var rep = r.report || {}
        if (r.account) updatePlan(r.account)
        var cost = r.usage ? "(" + (r.usage.latency_ms / 1000).toFixed(1) + "s, " + r.usage.credits + " credits)" : ""
        if (r.status === "question") {
            pendingKind = r.kind || "clarify"; pendingQuestion = r.question
            if (pendingKind === "confirm")
                say("bot", "", "confirm", "", (r.options || []).join("\n"), "", { title: r.question })
            else
                say("bot", "", pendingKind, (r.options || []).join("\n"), "", "", { title: r.question })
            return
        }
        if (r.status === "error") {
            if (r.error === "activate") {
                needActivation = true
                if (!r.no_email_help) lastBlocked = instruction
            }
            if ((r.error === "no_balance" || r.error === "plan_limit") && editsLeft !== "") editsLeft = "0"
            say(rep.buy_url ? "limit" : "error", rep.message || ("Error (HTTP " + httpStatus + ")."), "", "", "", rep.buy_url || "")
            resetRequest(); return
        }
        if (r.status === "applied") finishApplied(rep, r.edits || [], r.edit_notes || [], cost, r.edit_summary, r.buy_url || "", r.result, r.preview)
        else say("bot", rep.message || "Nothing to change.", "", "", [logText(rep), cost].filter(Boolean).join("\n"))
        resetRequest()
    }

    function handleReport(txt, rc) {
        var rep = null
        var j = txt.search(/^\{/m)
        if (j >= 0) { try { rep = JSON.parse(txt.substring(j)) } catch (e) { rep = null } }
        var head = (j >= 0 ? txt.substring(0, j) : txt).trim()

        if (rep && rep.status === "question") {
            pendingKind = rep.kind; pendingQuestion = rep.question
            var opts = (rep.options || []).join("\n")
            if (rep.kind === "confirm")
                say("bot", "", "confirm", "", (rep.options || []).join("\n"), "", { title: rep.question })
            else
                say("bot", "", rep.kind, opts, "", "", { title: rep.question })
            return
        }
        if (rc !== 0 || !rep) {
            say("error", "Something went wrong (exit " + rc + ").", "", "", txt.slice(-1500))
            resetRequest(); return
        }
        if (rep.status === "applied") finishApplied(rep, rep.edits || [], rep.edit_notes || [], "", rep.edit_summary)
        else say("bot", rep.message || head || "Nothing to change.", "", "", logText(rep))
        resetRequest()
    }

    function logText(rep) { return (rep.log || []).map(function(l) { return "- " + l }).join("\n") }

    function finishApplied(rep, edits, notes, cost, summary, buyUrl, result, previewState) {
        if (!curScore || curScore.scoreName !== job.target) {
            say("error", "The score \"" + job.target + "\" is no longer the active score, so nothing was changed. "
                + "Switch back to it and ask again.", "", ""); return
        }
        if (!edits.length) { say("error", "The service returned no edits to apply; nothing was changed.", "", ""); return }
        var res = applyEdits(edits)
        if (res.error) {
            say("error", "Could not apply the change in place (" + res.error + "); the score was left unchanged.",
                "", "", logText(rep)); return
        }
        var where = []
        var ch = summary || rep.changed || {}
        for (var k in ch) where.push(k.replace(/<\/?sym>|accidental/g, "").replace(/Flat/g, "♭").replace(/Sharp/g, "♯")
                                     + (/^\d/.test(String(ch[k])) ? " bars " : " ") + ch[k])
        var msg = where.length ? where.join("; ") : (rep.message || "")
        var extra = notes.concat(res.problems)
        var n = res.count.write || 0, card = result || {}
        say("bot", msg + (extra.length ? "\nNote: " + extra.join("; ") + "." : ""), "", "", logText(rep), buyUrl || "",
            { title: card.title || "Your edit is in the score", badge: n > 0 ? n + (n === 1 ? " note" : " notes") : "",
              cost: cost, undoHint: true, chips: (card.suggestions && card.suggestions.length) ? JSON.stringify(card.suggestions) : "" })
        if (previewState === "pending") waitForPreview(chat.count - 1)
    }

    // ---------- in-place edits (see edits.py for the op format) ----------
    readonly property int tpq: 480
    function gcd(a, b) { return b ? gcd(b, a % b) : a }
    function setDur(c, ticks) { var g = gcd(ticks, tpq * 4); c.setDuration(ticks / g, tpq * 4 / g) }
    function frac(ticks) { var g = gcd(ticks, tpq * 4); return fraction(ticks / g, tpq * 4 / g) }
    function normName(s) {
        return String(s || "").toLowerCase().replace(/<\/?sym>/g, "").replace(/accidentalflat|♭/g, "b")
            .replace(/accidentalsharp|♯/g, "#").replace(/[^a-z0-9#]/g, "")
    }
    function staffOf(op) {
        var p = curScore.parts[op.part]
        if (!p) throw "part " + (op.part + 1) + " not found"
        if (p.longName && op.name && normName(p.longName) !== normName(op.name))
            throw "part " + (op.part + 1) + " is \"" + p.longName + "\", expected \"" + op.name + "\""
        return p.startTrack / 4 + op.staff
    }
    // cursor on `track` at `tick`, even in an empty voice (rewind on voice 1, then switch track)
    function cursorAt(track, tick) {
        var c = curScore.newCursor()
        c.track = track - track % 4
        c.rewindToTick(tick)
        c.track = track
        return c
    }
    function sortedPitches(ch) {
        var a = []
        for (var i = 0; i < ch.notes.length; i++) a.push(ch.notes[i].pitch)
        return a.sort(function(x, y) { return x - y })
    }
    function samePitches(ch, ps) { return sortedPitches(ch).join(",") === ps.slice().sort(function(x, y) { return x - y }).join(",") }
    // chord on `staff` at `tick` (any voice) with these concert pitches
    function findChord(staff, tick, ps, grace) {
        for (var v = 0; v < 4; v++) {
            var c = curScore.newCursor(); c.track = staff * 4 + v; c.rewindToTick(tick)
            if (!c.segment || c.tick !== tick || !c.element || c.element.type !== Element.CHORD) continue
            var ch = c.element
            if (grace) {
                for (var g = 0; g < ch.graceNotes.length; g++)
                    if (samePitches(ch.graceNotes[g], ps)) return ch.graceNotes[g]
            } else if (samePitches(ch, ps)) return ch
        }
        return null
    }
    function voiceHasChords(track, t0, t1) {
        var c = curScore.newCursor(); c.track = track; c.rewindToTick(t0)
        while (c.segment && c.tick < t1) {
            if (c.tick >= t0 && c.element && c.element.type === Element.CHORD) return true
            if (!c.next()) break
        }
        return false
    }
    function elementsIn(track, t0, t1) {
        var out = [], c = curScore.newCursor(); c.track = track; c.rewindToTick(t0)
        while (c.segment && c.tick < t1) {
            if (c.tick >= t0 && c.element) out.push(c.element)
            if (!c.next()) break
        }
        return out
    }
    function setSpelling(note, tpc) {
        var delta = note.tpc2 - note.tpc1          // the staff's transposition, as MuseScore spelled it
        note.tpc1 = tpc; note.tpc2 = tpc + delta
    }

    // Drum staves: MuseScore's addNote moves every note to the voice its drumset entry says (bass drum
    // and pedal hi-hat = voice 2), ignoring the cursor's voice. A tuplet started on voice 1 then got
    // its notes in voice 2 and left both voices with the wrong length ("voice too long: 9/8 in 4/4",
    // nc-f4c7 2026-10-31). So split the events by drumset voice and write each voice on its own track.
    function drumsetOf(op) {
        try { var p = curScore.parts[op.part]; return (p && p.hasDrumStaff) ? p.instruments[0].drumset : null }
        catch (e) { return null }
    }
    function splitDrumEvents(ev, ds) {
        var byV = {}, used = [], i, k
        for (i = 0; i < ev.length; i++)
            for (k = 0; ev[i].n && k < ev[i].n.length; k++) {
                var dv = ds.voice(ev[i].n[k][0]); if (!(dv >= 0 && dv < 4)) dv = 0
                if (used.indexOf(dv) < 0) used.push(dv)
            }
        if (!used.length) used.push(0)
        for (var u = 0; u < used.length; u++) {
            var out = []
            for (i = 0; i < ev.length; i++) {
                var x = ev[i], y = { t: x.t, d: x.d }
                if (x.tup) y.tup = x.tup
                var ns = []
                for (k = 0; x.n && k < x.n.length; k++) {
                    var v2 = ds.voice(x.n[k][0]); if (!(v2 >= 0 && v2 < 4)) v2 = 0
                    if (v2 === used[u]) ns.push(x.n[k])
                }
                if (ns.length) y.n = ns; else y.rest = true
                out.push(y)
            }
            byV[used[u]] = collapseRestTuplets(out)
        }
        return { voices: used.sort(), events: byV }
    }
    // a tuplet group that is all rests in this drum voice -> one plain rest (no empty "3" brackets)
    function collapseRestTuplets(ev) {
        var out = []
        for (var i = 0; i < ev.length; i++) {
            var x = ev[i]
            if (!x.tup) { out.push(x); continue }
            var j = i, left = x.tup[2], allRest = true
            while (j < ev.length && left > 0) {
                if (!ev[j].rest) allRest = false
                left -= ev[j].d * x.tup[1] / x.tup[0]
                j++
            }
            if (allRest && left === 0) { out.push({ t: x.t, d: x.tup[2], rest: true }); i = j - 1 }
            else out.push(x)
        }
        return out
    }
    function writeEvents(op, st, staff, v, ev) {
        var track = staff * 4 + v
        var c = cursorAt(track, op.start)
        if (!c.segment || c.tick !== op.start) throw "cannot place the cursor in " + op.name
        var written = []
        for (var i = 0; i < ev.length; i++) {
            var x = ev[i]
            if (c.tick !== x.t || c.track !== track) {
                c = cursorAt(track, x.t)
                if (c.tick !== x.t) { st.problems.push(op.name + ": skipped a note at tick " + x.t); continue }
            }
            if (x.tup) c.addTuplet(fraction(x.tup[0], x.tup[1]), frac(x.tup[2]))
            setDur(c, x.d)
            if (x.rest) { c.addRest(); continue }
            c.addNote(x.n[0][0])
            for (var j = 1; j < x.n.length; j++) c.addNote(x.n[j][0], true)
            written.push(x)
        }
        return written
    }
    function opWrite(op, st) {
        var staff = staffOf(op), v = 0
        var ds = drumsetOf(op)
        if (ds) {
            // drum voices are fixed by the drumset: clear the written voices (all of them on replace)
            var sp = splitDrumEvents(op.events, ds)
            if (op.replace)
                for (var k3 = 0; k3 < 4; k3++) {
                    if (sp.voices.indexOf(k3) >= 0) continue        // overwritten below anyway
                    for (var pass3 = 0; pass3 < 2; pass3++) {       // chords -> rests -> gone
                        var els3 = elementsIn(staff * 4 + k3, op.start, op.end)
                        for (var e3 = 0; e3 < els3.length; e3++) removeElement(els3[e3])
                    }
                }
            var n3 = 0
            for (var dvi = 0; dvi < sp.voices.length; dvi++) {
                var wr = writeEvents(op, st, staff, sp.voices[dvi], sp.events[sp.voices[dvi]])
                n3 += wr.length
            }
            st.count.write = (st.count.write || 0) + n3
            st.touched.push({ staff: staff, start: op.start, end: op.end })
            return
        }
        if (op.voice === "new") {
            v = -1
            for (var k = 1; k < 4; k++) if (!voiceHasChords(staff * 4 + k, op.start, op.end)) { v = k; break }
            if (v < 0) throw op.name + " has no free voice in that range"
        } else if (op.replace) {
            for (var k2 = 1; k2 < 4; k2++)
                for (var pass = 0; pass < 2; pass++) {            // chords -> rests -> gone
                    var els = elementsIn(staff * 4 + k2, op.start, op.end)
                    for (var e = 0; e < els.length; e++) removeElement(els[e])
                }
        }
        var track = staff * 4 + v
        var written = writeEvents(op, st, staff, v, op.events)
        st.touched.push({ staff: staff, start: op.start, end: op.end })
        // spelling (tpc) + stems on what was just written; follow ties MuseScore added at barlines
        for (var w = 0; w < written.length; w++) {
            var cc = cursorAt(track, written[w].t), ch = cc.element
            if (!ch || ch.type !== Element.CHORD || cc.tick !== written[w].t) continue
            var want = written[w].n
            for (var n = 0; n < ch.notes.length && n < want.length; n++) {
                var note = ch.notes[n], hops = 0
                while (note && hops++ < 8) {
                    setSpelling(note, want[n][1])
                    var tie = note.tieForward
                    note = tie ? tie.endNote : null
                }
            }
            if (op.stem && v > 0) ch.stemDirection = op.stem === "up" ? Direction.UP : Direction.DOWN
        }
        if (op.stem === "up" && v > 0) {          // doubled line sits above: existing voice 1 stems down
            var olds = elementsIn(staff * 4, op.start, op.end)
            for (var o = 0; o < olds.length; o++) if (olds[o].type === Element.CHORD) olds[o].stemDirection = Direction.DOWN
        }
        st.count.write = (st.count.write || 0) + written.length
    }
    function opPitches(op, st) {
        var staff = staffOf(op), miss = 0
        for (var i = 0; i < op.chords.length; i++) {
            var x = op.chords[i], ch = findChord(staff, x.t, x.old, !!x.grace)
            if (!ch) { miss++; continue }
            var notes = []
            for (var k = 0; k < ch.notes.length; k++) notes.push(ch.notes[k])
            notes.sort(function(a, b) { return a.pitch - b.pitch })
            for (var n = 0; n < notes.length && n < x["new"].length; n++) {
                var delta = notes[n].tpc2 - notes[n].tpc1
                notes[n].pitch = x["new"][n][0]
                notes[n].tpc1 = x["new"][n][1]; notes[n].tpc2 = x["new"][n][1] + delta
            }
            st.count.pitches = (st.count.pitches || 0) + 1
        }
        if (miss) st.problems.push(op.name + ": " + miss + " note(s) not found (score changed?), left as they were")
    }
    readonly property var articSym: ({ staccato: "articStaccatoAbove", accent: "articAccentAbove", tenuto: "articTenutoAbove" })
    function opArtic(op, st) {
        var staff = staffOf(op), miss = 0, sym = SymId[articSym[op.type]]
        if (sym === undefined) throw "unknown articulation " + op.type
        for (var i = 0; i < op.chords.length; i++) {
            var x = op.chords[i], ch = findChord(staff, x.t, x.p, false)
            if (!ch) { miss++; continue }
            var has = false
            for (var a = 0; a < ch.articulations.length; a++) if (ch.articulations[a].symbol === sym) has = true
            if (has) continue
            var art = newElement(Element.ARTICULATION); art.symbol = sym; ch.add(art)
            st.count.artic = (st.count.artic || 0) + 1
        }
        if (miss) st.problems.push(op.name + ": " + miss + " " + op.type + "(s) skipped (note not found)")
    }
    function opSlur(op, st) {
        var staff = staffOf(op), miss = 0
        for (var i = 0; i < op.slurs.length; i++) {
            var x = op.slurs[i]
            var a = findChord(staff, x.t1, x.p1, false), b = findChord(staff, x.t2, x.p2, false)
            if (!a || !b) { miss++; continue }
            var sl = newElement(Element.SLUR)
            sl.spannerTick = frac(x.t1)
            sl.track = a.track
            var c = curScore.newCursor(); c.track = a.track; c.rewindToTick(x.t1)
            c.add(sl)
            sl.spannerTicks = frac(x.t2 - x.t1)
            sl.spannerTrack2 = b.track
            st.count.slur = (st.count.slur || 0) + 1
        }
        if (miss) st.problems.push(op.name + ": " + miss + " slur(s) skipped (note not found)")
    }

    // cursor on `staff` at exactly `tick` on any voice that has a chord/rest there
    function cursorWithElement(staff, tick) {
        for (var v = 0; v < 4; v++) {
            var c = curScore.newCursor(); c.track = staff * 4 + v; c.rewindToTick(tick)
            if (c.segment && c.tick === tick && c.element) return c
        }
        return null
    }
    function dynSym(txt) {
        var map = { p: "dynamicPiano", m: "dynamicMezzo", f: "dynamicForte", s: "dynamicSforzando",
                    z: "dynamicZ", r: "dynamicRinforzando", n: "dynamicNiente" }
        var out = ""
        for (var i = 0; i < txt.length; i++) {
            if (!map[txt[i]]) return txt
            out += "<sym>" + map[txt[i]] + "</sym>"
        }
        return out
    }
    function opMark(op, st) {
        var staff = staffOf(op), miss = 0
        for (var i = 0; i < op.marks.length; i++) {
            var x = op.marks[i], c = cursorWithElement(staff, x.t)
            if (!c) { miss++; continue }
            var el
            if (x.kind === "dyn") {
                var ann = c.segment.annotations                  // a new dynamic replaces the one already there
                for (var a = 0; ann && a < ann.length; a++)
                    if (ann[a].type === Element.DYNAMIC && ann[a].track - ann[a].track % 4 === c.track - c.track % 4) removeElement(ann[a])
                el = newElement(Element.DYNAMIC); c.add(el); el.text = dynSym(String(x.text))
            }
            else if (x.kind === "harmony") { el = newElement(Element.HARMONY); c.add(el); el.text = String(x.text) }   // HARMONY: add BEFORE setting text (else MS crashes)
            else { el = newElement(Element.STAFF_TEXT); el.text = String(x.text); c.add(el) }
            st.count.mark = (st.count.mark || 0) + 1
        }
        if (miss) st.problems.push(op.name + ": " + miss + " marking(s) skipped (no note there)")
    }
    function opHairpin(op, st) {
        var staff = staffOf(op), miss = 0
        for (var i = 0; i < op.pins.length; i++) {
            var x = op.pins[i], c = cursorWithElement(staff, x.t1)
            if (!c) { miss++; continue }
            var hp = newElement(Element.HAIRPIN)
            hp.hairpinType = x.type === "dim" ? 1 : 0
            hp.spannerTick = frac(x.t1)
            hp.track = c.track
            c.add(hp)
            hp.spannerTicks = frac(x.t2 - x.t1)
            st.count.hairpin = (st.count.hairpin || 0) + 1
        }
        if (miss) st.problems.push(op.name + ": " + miss + " hairpin(s) skipped (no note there)")
    }

    // ---- score-level edits. Each one is best-effort: a failure is reported as a note with the manual
    // steps and never rolls back the note edits of the same request.
    // Written-minus-concert key offset of a staff in fifths (Bb trumpet +2, F horn +1, Eb alto +3):
    // tpc2 - tpc1 of the first note on the staff. cursor.add(KEYSIG) does NOT transpose by itself.
    function keyOffset(s) {
        var c = curScore.newCursor(); c.staffIdx = s; c.voice = 0; c.rewind(0)
        while (c.segment) {
            var e = c.element
            if (e && e.type === Element.CHORD && e.notes.length) return e.notes[0].tpc2 - e.notes[0].tpc1
            if (!c.next()) break
        }
        return 0
    }
    function opKeySig(op, st) {
        var done = 0
        for (var s = 0; s < curScore.nstaves; s++) {
            try {
                var c = curScore.newCursor(); c.staffIdx = s; c.voice = 0; c.rewindToTick(op.t)
                if (!c.segment || c.tick !== op.t) continue
                var ks = newElement(Element.KEYSIG), w = op.fifths + keyOffset(s)
                if (w > 7) w -= 12; else if (w < -7) w += 12
                ks.concertKey = op.fifths
                ks.actualKey = w
                c.add(ks); done++
            } catch (e) { console.log("copilot keysig staff " + s + ": " + e) }
        }
        if (done) st.count.keysig = done
        else st.problems.push("couldn't set the key signature from here: drag the key from the Key signatures palette onto bar " + op.bar)
    }
    readonly property var textMeta: ({ title: "workTitle", subtitle: "subtitle", composer: "composer", lyricist: "lyricist" })
    function opText(op, st) {
        try { curScore.setMetaTag(textMeta[op.field] || op.field, op.text) } catch (e0) {}
        // An existing title/composer... text in the top frame is rewritten in place (addText alone
        // would stack a second title on top of the old one).
        try {
            var tid = { title: Tid.TITLE, subtitle: Tid.SUBTITLE, composer: Tid.COMPOSER, lyricist: Tid.LYRICIST }[op.field]
            var mb = curScore.firstMeasure, found = null
            while (mb && mb.prev) mb = mb.prev
            for (; tid !== undefined && mb && mb.type !== Element.MEASURE && !found; mb = mb.next) {
                var els = mb.elements || []
                for (var i = 0; i < els.length; i++) {
                    if (els[i].subStyle !== tid) continue
                    if (!found) { found = els[i]; found.text = op.text } else removeElement(els[i])
                }
            }
            if (found) { st.count.text = (st.count.text || 0) + 1; return }
        } catch (e1) { console.log("copilot text in frame: " + e1) }
        try { curScore.addText(op.field, op.text); st.count.text = (st.count.text || 0) + 1 }
        catch (e) { st.problems.push("couldn't add the " + op.field + " text: use Add > Text > " + op.field) }
    }
    function layoutBreakType(t) {
        try { return t === "page" ? LayoutBreak.PAGE : LayoutBreak.LINE } catch (e) { return t === "page" ? 0 : 1 }
    }
    function measureAt(tick) {
        var c = curScore.newCursor(); c.track = 0; c.rewindToTick(tick)
        return (c.segment && c.measure) ? { cursor: c, measure: c.measure } : null
    }
    function opLayout(op, st) {
        var miss = 0
        if (op.clear) {                        // drop existing system breaks in the range first
            try {
                var m = measureAt(op.clear[0]) ? measureAt(op.clear[0]).measure : null
                while (m && m.firstSegment && m.firstSegment.tick <= op.clear[1]) {
                    var els = m.elements || []
                    for (var i = els.length - 1; i >= 0; i--)
                        if (els[i].type === Element.LAYOUT_BREAK && els[i].layoutBreakType === layoutBreakType("line"))
                            removeElement(els[i])
                    m = m.nextMeasure
                }
            } catch (e0) { console.log("copilot layout clear: " + e0) }
        }
        for (var b = 0; b < op.breaks.length; b++) {
            var x = op.breaks[b], at = measureAt(x.t)
            if (!at) { miss++; continue }
            try {
                var lb = newElement(Element.LAYOUT_BREAK)
                lb.layoutBreakType = layoutBreakType(x.type)
                at.cursor.add(lb)
                st.count.layout = (st.count.layout || 0) + 1
            } catch (e) { miss++; console.log("copilot layout break: " + e) }
        }
        if (miss) st.problems.push(miss + " break(s) not added: select the bar and press Enter (system break) or Ctrl+Enter (page break)")
    }

    // Lyrics (0.8): one syllable per existing chord. syllabic: MuseScore SINGLE 0, BEGIN 1, END 2, MIDDLE 3.
    readonly property var sylCode: ({ single: 0, begin: 1, end: 2, middle: 3 })
    function opLyrics(op, st) {
        var staff = staffOf(op), miss = 0, verse = Math.max(0, (op.verse || 1) - 1)
        for (var i = 0; i < op.items.length; i++) {
            var x = op.items[i], ch = findChord(staff, x.t, x.p, false)
            if (!ch) { miss++; continue }
            var old = ch.lyrics || []
            for (var o = old.length - 1; o >= 0; o--) if (old[o].verse === verse) removeElement(old[o])
            var l = newElement(Element.LYRICS)
            l.text = String(x.text)
            l.verse = verse
            l.track = ch.track
            ch.add(l)
            try { l.syllabic = sylCode[x.syl] || 0 } catch (e1) { }
            if (x.ext) { try { l.lyricTicks = frac(x.ext) } catch (e2) { } }
            st.count.lyrics = (st.count.lyrics || 0) + 1
        }
        if (miss) st.problems.push(op.name + ": " + miss + " syllable(s) skipped (note not found)")
    }

    // After the edits, BEFORE endCmd: every voice of every bar a write touched must still fit its bar
    // (voice 1 exactly, voices 2-4 at most). Otherwise the whole request is rolled back.
    function measureAtTick(tick) {
        var c = curScore.newCursor(); c.track = 0; c.rewindToTick(tick)
        return c.segment ? c.measure : null
    }
    function checkBars(st) {
        var bad = []
        for (var i = 0; i < st.touched.length && bad.length < 4; i++) {
            var r = st.touched[i], m = measureAtTick(r.start), guard = 0
            while (m && m.firstSegment && m.firstSegment.tick < r.end && guard++ < 2000) {
                var t0 = m.firstSegment.tick, len = m.ticks.ticks, t1 = t0 + len
                for (var v = 0; v < 4; v++) {
                    var c = curScore.newCursor(); c.track = r.staff * 4 + v; c.rewindToTick(t0)
                    var sum = 0, endT = t0
                    while (c.segment && c.tick < t1) {
                        var e = c.element
                        if (e && c.tick >= t0 && (e.type === Element.CHORD || e.type === Element.REST)) {
                            var a = e.actualDuration ? e.actualDuration.ticks : e.duration.ticks
                            sum += a; endT = Math.max(endT, c.tick + a)
                        }
                        if (!c.next()) break
                    }
                    if (sum > len || endT > t1 || (v === 0 && sum > 0 && sum < len))
                        bad.push("bar " + (m.no + 1) + " staff " + (r.staff + 1) + " voice " + (v + 1)
                                 + " (" + sum + "/" + len + " ticks)")
                }
                m = m.nextMeasure
            }
        }
        return bad
    }

    // Applies all ops as ONE undo step. Throws nothing; returns {error} or {problems, count}.
    function applyEdits(ops) {
        var st = { problems: [], count: {}, touched: [] }
        curScore.startCmd("Scorehand")
        try {
            for (var i = 0; i < ops.length; i++) {
                var op = ops[i]
                if (op.op === "write") opWrite(op, st)
                else if (op.op === "pitches") opPitches(op, st)
                else if (op.op === "artic") opArtic(op, st)
                else if (op.op === "slur") opSlur(op, st)
                else if (op.op === "mark") opMark(op, st)
                else if (op.op === "hairpin") opHairpin(op, st)
                else if (op.op === "keysig") opKeySig(op, st)
                else if (op.op === "text") opText(op, st)
                else if (op.op === "layout") opLayout(op, st)
                else if (op.op === "lyrics") opLyrics(op, st)
                else st.problems.push("unsupported edit \"" + op.op + "\" skipped (update the plugin)")
            }
        } catch (e) {
            curScore.endCmd(true)                 // roll back everything from this request
            console.log("copilot apply failed: " + e)
            return { error: String(e) }
        }
        var bad = []
        try { bad = checkBars(st) } catch (e4) { console.log("copilot bar check: " + e4) }
        if (bad.length) {
            curScore.endCmd(true)
            console.log("copilot bar check failed: " + bad.join("; "))
            return { error: "it would have left " + bad.join(", ") + " with the wrong length" }
        }
        curScore.endCmd()
        console.log("copilot applied in place: " + JSON.stringify(st.count))
        return st
    }
}