import QtQuick
import Quickshell
import Quickshell.Wayland
import "." as M
import "../services" as S
import NovaStats as NS

// Bar panel - fullscreen transparent window so content can resize freely
// without triggering Wayland surface resizes.
//
// Parent drives visibility via showPanel. Click-outside or Esc dismisses
// and emits dismissed(). Pass anchorItem for lazy position computation.
PanelWindow {
    id: root

    property bool showPanel: false
    property Item anchorItem: null
    signal dismissed

    required property color accentColor
    property string panelNamespace: "nova-panel"
    property real contentWidth: 220

    default property alias content: panelContent.children

    visible: _winVisible
    color: "transparent"

    property bool _winVisible: false

    WlrLayershell.layer: WlrLayer.Overlay
    WlrLayershell.exclusiveZone: 0
    WlrLayershell.namespace: root.panelNamespace

    property real topMargin: 0

    anchors.top: true
    anchors.left: true
    anchors.right: true
    anchors.bottom: true

    margins.top: topMargin

    function _updatePosition() {
        const scr = screen;
        const sw = scr?.width ?? 1920;
        let cx;
        if (root.anchorItem) {
            const pt = root.anchorItem.mapToGlobal(root.anchorItem.width / 2, 0);
            cx = pt.x - (scr?.x ?? 0);
        } else {
            cx = sw / 2;
        }
        panelContainer.x = Math.max(0, Math.min(Math.round(cx - root.contentWidth / 2), sw - root.contentWidth));
    }

    // Grace period: after _show(), suppress click-outside dismiss briefly so
    // Niri has time to route wl_pointer.enter to the new overlay surface.
    property bool _grace: false
    Timer {
        id: _graceTimer
        interval: 400
        onTriggered: root._grace = false
    }

    // Content-change grace: call keepOpen(ms) when panel content is about to
    // resize/rebuild (session switch, device list change, etc.).
    property bool _contentBusy: false
    Timer {
        id: _contentBusyTimer
        onTriggered: root._contentBusy = false
    }
    function keepOpen(ms) {
        _contentBusy = true;
        _contentBusyTimer.interval = ms ?? 400;
        _contentBusyTimer.restart();
    }

    function _show() {
        _updatePosition();
        if (!hideAnim.running) {
            panelContainer.y = -(panelContainer.height > 0 ? panelContainer.height : 400);
            panelContainer.opacity = 0;
        }
        _winVisible = true;
        hideAnim.stop();
        if (S.ThemeUtil.reducedMotion) {
            panelContainer.opacity = 1;
            panelContainer.y = 0;
        } else {
            showAnim.start();
        }
        _grace = true;
        _graceTimer.restart();
    }

    function dismiss() {
        if (!_winVisible)
            return;
        showAnim.stop();
        if (S.ThemeUtil.reducedMotion) {
            _winVisible = false;
            dismissed();
        } else {
            hideAnim.start();
        }
        _grace = false;
        _graceTimer.stop();
    }

    onShowPanelChanged: {
        if (showPanel) {
            if (!_winVisible || hideAnim.running)
                _show();
        } else {
            dismiss();
        }
    }

    ParallelAnimation {
        id: showAnim
        NumberAnimation {
            target: panelContainer
            property: "opacity"
            to: 1
            duration: 120
            easing.type: Easing.OutCubic
        }
        NumberAnimation {
            target: panelContainer
            property: "y"
            to: 0
            duration: 150
            easing.type: Easing.OutCubic
        }
    }

    ParallelAnimation {
        id: hideAnim
        NumberAnimation {
            target: panelContainer
            property: "opacity"
            to: 0
            duration: 150
            easing.type: Easing.InCubic
        }
        NumberAnimation {
            target: panelContainer
            property: "y"
            to: -panelContainer.height
            duration: 150
            easing.type: Easing.InCubic
        }
        onFinished: {
            root._winVisible = false;
            root.dismissed();
        }
    }

    // Click-outside dismiss.
    // TapHandler fires for all taps; position check skips taps inside panelContainer.
    // Gated on !_grace so spurious events during the opening window don't dismiss.
    Item {
        anchors.fill: parent

        TapHandler {
            enabled: !root._grace
            onTapped: {
                const p = point.position;
                const pad = 8;
                if (p.x < panelContainer.x - pad || p.x > panelContainer.x + panelContainer.width + pad || p.y < panelContainer.y - pad || p.y > panelContainer.y + panelContainer.height + pad)
                    root.dismiss();
            }
        }
    }

    // Esc dismiss
    Shortcut {
        sequence: "Escape"
        enabled: root._winVisible
        onActivated: root.dismiss()
    }

    M.PopupBackground {
        x: panelContainer.x
        y: panelContainer.y
        width: panelContainer.width
        height: panelContainer.height
        opacity: panelContainer.opacity * Math.max(NS.ThemeService.barOpacity, 0.85)
        accentColor: root.accentColor
    }

    Item {
        id: panelContainer
        x: 0
        y: 0
        width: root.contentWidth
        height: _panelColumn.height
        opacity: 0

        Column {
            id: _panelColumn
            width: root.contentWidth

            Flickable {
                id: _flickable
                width: parent.width
                height: Math.min(panelContent.height, _maxContentHeight)
                contentHeight: panelContent.height
                clip: contentHeight > height
                boundsBehavior: Flickable.StopAtBounds

                readonly property real _maxContentHeight: (root.screen?.height ?? 1080) * 0.6

                Column {
                    id: panelContent
                    width: parent.width
                }
            }
        }
    }

    // Border overlay - on top of content so full-bleed items don't cover it
    Rectangle {
        x: panelContainer.x
        y: panelContainer.y
        width: panelContainer.width
        height: panelContainer.height
        color: "transparent"
        border.color: root.accentColor
        border.width: 1
        radius: NS.ThemeService.radius
        opacity: panelContainer.opacity
    }
}