import QtQuick
import QtQuick.Controls
import QtQuick.Layouts

// A compact date picker for a section's SCHEDULED/DEADLINE planning
// timestamp. Supports the common point-timestamp forms the parser handles:
// a date, an optional time (HH:MM), and an optional repeater (e.g. +1w).
// Planning timestamps are active by org convention, so the server wraps the
// value in <...>. Set writes the field, Clear removes it.
//
// Open with open(row, field, currentValue), where field is "SCHEDULED" or
// "DEADLINE" and currentValue is the field's current <...> string (may be
// empty). The dialog parses currentValue to prefill its controls.
Dialog {
    id: dpd
    title: qsTr("Set Date")
    modal: true
    standardButtons: Dialog.NoButton
    width: 340

    x: (parent.width - width) / 2
    y: (parent.height - height) / 2

    // Target section row and planning field.
    property int targetRow: -1
    property string field: "SCHEDULED"

    // Mode: "planning" writes a SCHEDULED/DEADLINE field; "insert" emits the
    // built timestamp for a caller to insert (e.g. into a body editor at the
    // cursor). In insert mode `insertActive` chooses <...> vs [...].
    property string mode: "planning"
    property bool insertActive: true
    signal timestampAccepted(string ts)

    // Calendar state.
    property int shownMonth: (new Date()).getMonth()   // 0-11
    property int shownYear: (new Date()).getFullYear()
    // Selected date components (-1 day = none selected yet).
    property int selYear: -1
    property int selMonth: -1
    property int selDay: -1

    readonly property var monthNames: [
        qsTr("January"), qsTr("February"), qsTr("March"), qsTr("April"),
        qsTr("May"), qsTr("June"), qsTr("July"), qsTr("August"),
        qsTr("September"), qsTr("October"), qsTr("November"), qsTr("December")
    ]
    readonly property var dayNames: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"]

    background: Rectangle {
        color: theme.windowColor
        border.color: theme.midColor
        border.width: 1
        radius: 6
    }

    // Open the picker for a given row/field, prefilled from currentValue.
    function open2(row, fieldName, currentValue) {
        mode = "planning"
        targetRow = row
        field = fieldName
        parseValue(currentValue)
        open()
    }

    // Open the picker in insert mode. On Set it emits timestampAccepted with
    // the built <...> (or [...]) timestamp instead of writing a field.
    function openInsert() {
        mode = "insert"
        parseValue("")
        open()
    }

    // Parse an org timestamp like "<2025-01-15 Wed 10:30 +1w>" into the
    // dialog's controls. An empty/unparseable value leaves today selected and
    // the time/repeater empty.
    function parseValue(v) {
        timeField.text = ""
        repeaterField.text = ""
        var now = new Date()
        selYear = now.getFullYear(); selMonth = now.getMonth(); selDay = now.getDate()
        if (v && v.length > 0) {
            // Strip surrounding < > or [ ].
            var inner = v.replace(/^[<\[]/, "").replace(/[>\]]$/, "").trim()
            var dm = inner.match(/^(\d{4})-(\d{2})-(\d{2})/)
            if (dm) {
                selYear = parseInt(dm[1]); selMonth = parseInt(dm[2]) - 1; selDay = parseInt(dm[3])
            }
            var tm = inner.match(/\b(\d{1,2}:\d{2})\b/)
            if (tm) timeField.text = tm[1]
            var rm = inner.match(/((?:\+\+|\.\+|\+)\d+[hdwmy])/)
            if (rm) repeaterField.text = rm[1]
        }
        shownMonth = selMonth
        shownYear = selYear
    }

    function prevMonth() {
        if (shownMonth === 0) { shownMonth = 11; shownYear-- } else shownMonth--
    }
    function nextMonth() {
        if (shownMonth === 11) { shownMonth = 0; shownYear++ } else shownMonth++
    }

    // Build the inner timestamp string "YYYY-MM-DD Day [HH:MM] [repeater]".
    function buildTimestamp() {
        if (selYear < 0) return ""
        var mm = (selMonth + 1 < 10 ? "0" : "") + (selMonth + 1)
        var dd = (selDay < 10 ? "0" : "") + selDay
        var dow = dayNames[(new Date(selYear, selMonth, selDay)).getDay()]
        var s = selYear + "-" + mm + "-" + dd + " " + dow
        var t = timeField.text.trim()
        if (/^\d{1,2}:\d{2}$/.test(t)) s += " " + t
        var r = repeaterField.text.trim()
        if (/^(?:\+\+|\.\+|\+)\d+[hdwmy]$/.test(r)) s += " " + r
        return s
    }

    function applySet() {
        var ts = buildTimestamp()
        if (ts.length === 0) { close(); return }
        if (mode === "insert") {
            var wrapped = insertActive ? "<" + ts + ">" : "[" + ts + "]"
            timestampAccepted(wrapped)
            close()
            return
        }
        if (field === "DEADLINE")
            docModel.setDeadline(targetRow, ts)
        else
            docModel.setScheduled(targetRow, ts)
        close()
    }

    function applyClear() {
        if (field === "DEADLINE")
            docModel.setDeadline(targetRow, "")
        else
            docModel.setScheduled(targetRow, "")
        close()
    }

    contentItem: ColumnLayout {
        spacing: 10

        // Mode-dependent selector: Scheduled/Deadline (planning) or
        // Active/Inactive (insert).
        RowLayout {
            Layout.fillWidth: true
            spacing: 6
            visible: dpd.mode === "planning"
            RadioButton {
                text: qsTr("Scheduled")
                checked: dpd.field === "SCHEDULED"
                onClicked: dpd.field = "SCHEDULED"
            }
            RadioButton {
                text: qsTr("Deadline")
                checked: dpd.field === "DEADLINE"
                onClicked: dpd.field = "DEADLINE"
            }
        }

        // Insert-mode selector: active <...> vs inactive [...].
        RowLayout {
            Layout.fillWidth: true
            spacing: 6
            visible: dpd.mode === "insert"
            RadioButton {
                text: qsTr("Active <>")
                checked: dpd.insertActive
                onClicked: dpd.insertActive = true
            }
            RadioButton {
                text: qsTr("Inactive []")
                checked: !dpd.insertActive
                onClicked: dpd.insertActive = false
            }
        }

        // Month/year navigation.
        RowLayout {
            Layout.fillWidth: true
            Button { text: "‹"; onClicked: dpd.prevMonth() }
            Label {
                Layout.fillWidth: true
                horizontalAlignment: Text.AlignHCenter
                text: dpd.monthNames[dpd.shownMonth] + " " + dpd.shownYear
                color: theme.textColor
                font.bold: true
            }
            Button { text: "›"; onClicked: dpd.nextMonth() }
        }

        DayOfWeekRow {
            Layout.fillWidth: true
            locale: grid.locale
            delegate: Label {
                text: model.shortName
                color: theme.placeholderTextColor
                font.pointSize: Math.max(8, (theme.fontSize > 0 ? theme.fontSize : 11) - 2)
                horizontalAlignment: Text.AlignHCenter
            }
        }

        MonthGrid {
            id: grid
            Layout.fillWidth: true
            month: dpd.shownMonth
            year: dpd.shownYear

            delegate: Rectangle {
                required property var model
                readonly property bool inMonth: model.month === dpd.shownMonth
                readonly property bool isSelected:
                    model.year === dpd.selYear && model.month === dpd.selMonth
                    && model.day === dpd.selDay
                implicitWidth: 36
                implicitHeight: 28
                radius: 4
                color: isSelected ? theme.highlightColor
                       : (dayHover.hovered && inMonth ? theme.alternateBaseColor
                                                      : "transparent")
                Label {
                    anchors.centerIn: parent
                    text: model.day
                    color: !inMonth ? theme.placeholderTextColor
                           : (parent.isSelected ? theme.highlightedTextColor
                                                : theme.textColor)
                    font.pointSize: theme.fontSize > 0 ? theme.fontSize - 1 : 10
                }
                HoverHandler { id: dayHover }
                TapHandler {
                    onTapped: {
                        dpd.selYear = model.year
                        dpd.selMonth = model.month
                        dpd.selDay = model.day
                        // Follow the click into adjacent months.
                        dpd.shownMonth = model.month
                        dpd.shownYear = model.year
                    }
                }
            }
        }

        // Optional time and repeater.
        GridLayout {
            Layout.fillWidth: true
            columns: 2
            columnSpacing: 8
            rowSpacing: 6

            Label { text: qsTr("Time"); color: theme.textColor }
            TextField {
                id: timeField
                Layout.fillWidth: true
                placeholderText: qsTr("HH:MM (optional)")
                inputMask: ""
                selectByMouse: true
            }

            Label { text: qsTr("Repeat"); color: theme.textColor }
            TextField {
                id: repeaterField
                Layout.fillWidth: true
                placeholderText: qsTr("+1w / ++1m / .+2d (optional)")
                selectByMouse: true
            }
        }

        // Actions.
        RowLayout {
            Layout.fillWidth: true
            spacing: 6
            Button {
                text: qsTr("Clear")
                visible: dpd.mode === "planning"
                onClicked: dpd.applyClear()
            }
            Item { Layout.fillWidth: true }
            Button {
                text: qsTr("Cancel")
                onClicked: dpd.close()
            }
            Button {
                text: dpd.mode === "insert" ? qsTr("Insert") : qsTr("Set")
                highlighted: true
                onClicked: dpd.applySet()
            }
        }
    }
}