import QtQuick
import "../services" as S
import NovaStats as NS

Column {
    id: root

    required property color accentColor
    required property date currentDate

    readonly property var _locale: Qt.locale()
    readonly property int _year: currentDate.getFullYear()
    readonly property int _month: currentDate.getMonth()
    readonly property int _day: currentDate.getDate()
    readonly property int _firstDayOfWeek: _locale.firstDayOfWeek

    // Week number (ISO 8601)
    function _weekNumber(d) {
        const tmp = new Date(d.getTime());
        tmp.setHours(0, 0, 0, 0);
        tmp.setDate(tmp.getDate() + 3 - (tmp.getDay() + 6) % 7);
        const jan4 = new Date(tmp.getFullYear(), 0, 4);
        return 1 + Math.round(((tmp.getTime() - jan4.getTime()) / 86400000 - 3 + (jan4.getDay() + 6) % 7) / 7);
    }

    // Build 6x7 grid of day numbers for the current month view
    readonly property var _calendarDays: {
        const first = new Date(_year, _month, 1);
        const firstDow = first.getDay();
        // Offset: how many days from previous month to show
        let offset = (firstDow - _firstDayOfWeek + 7) % 7;
        const startDate = new Date(_year, _month, 1 - offset);
        const days = [];
        for (let i = 0; i < 42; i++) {
            const d = new Date(startDate.getTime() + i * 86400000);
            days.push({
                day: d.getDate(),
                month: d.getMonth(),
                year: d.getFullYear(),
                isCurrentMonth: d.getMonth() === _month,
                isToday: d.getDate() === _day && d.getMonth() === _month && d.getFullYear() === _year
            });
        }
        return days;
    }

    // Weekday header names (short, locale-aware)
    readonly property var _dayNames: {
        const names = [];
        for (let i = 0; i < 7; i++) {
            const idx = (_firstDayOfWeek + i) % 7;
            names.push(_locale.dayName(idx, Locale.NarrowFormat));
        }
        return names;
    }

    // Date header
    Item {
        width: parent.width
        height: 28

        Text {
            anchors.left: parent.left
            anchors.leftMargin: 12
            anchors.verticalCenter: parent.verticalCenter
            text: root._locale.standaloneMonthName(root._month, Locale.LongFormat) + " " + root._year
            color: root.accentColor
            font.pixelSize: NS.ThemeService.fontSize
            font.family: NS.ThemeService.fontFamily
            font.bold: true
        }

        Text {
            anchors.right: parent.right
            anchors.rightMargin: 12
            anchors.verticalCenter: parent.verticalCenter
            text: "W" + root._weekNumber(root.currentDate)
            color: NS.ThemeService.base04
            font.pixelSize: NS.ThemeService.fontSize - 2
            font.family: NS.ThemeService.fontFamily
        }
    }

    // Day-of-week headers
    Row {
        anchors.horizontalCenter: parent.horizontalCenter
        Repeater {
            model: root._dayNames
            Text {
                required property string modelData
                width: Math.floor((root.width - 24) / 7)
                height: 18
                horizontalAlignment: Text.AlignHCenter
                text: modelData
                color: NS.ThemeService.base04
                font.pixelSize: NS.ThemeService.fontSize - 3
                font.family: NS.ThemeService.fontFamily
                font.bold: true
            }
        }
    }

    // Calendar grid (6 rows x 7 cols)
    Grid {
        anchors.horizontalCenter: parent.horizontalCenter
        columns: 7
        Repeater {
            model: root._calendarDays
            Item {
                required property var modelData
                width: Math.floor((root.width - 24) / 7)
                height: Math.floor((root.width - 24) / 7)

                Rectangle {
                    anchors.centerIn: parent
                    width: Math.min(parent.width, parent.height) - 4
                    height: width
                    radius: width / 2
                    color: modelData.isToday ? root.accentColor : "transparent"
                }

                Text {
                    anchors.centerIn: parent
                    text: modelData.day
                    color: modelData.isToday ? NS.ThemeService.base00 : modelData.isCurrentMonth ? NS.ThemeService.base05 : NS.ThemeService.base03
                    font.pixelSize: NS.ThemeService.fontSize - 1
                    font.family: NS.ThemeService.fontFamily
                    font.bold: modelData.isToday
                }
            }
        }
    }

    // Full date line
    Text {
        width: parent.width - 24
        anchors.horizontalCenter: parent.horizontalCenter
        horizontalAlignment: Text.AlignHCenter
        text: root.currentDate.toLocaleDateString(root._locale, Locale.LongFormat)
        color: NS.ThemeService.base04
        font.pixelSize: NS.ThemeService.fontSize - 2
        font.family: NS.ThemeService.fontFamily
    }

    Item {
        width: 1
        height: 4
    }
}