import QtQuick
import Quickshell
import qs.Common
import qs.Services

QtObject {
    id: manager

    property var modelData
    property int topMargin: 0
    property int baseNotificationHeight: 120
    property int maxTargetNotifications: 3
    property var popupWindows: [] // strong refs to windows (live until exitFinished)
    property var destroyingWindows: new Set()
    property Component popupComponent

    popupComponent: Component {
        NotificationPopup {
            onEntered: manager._onPopupEntered(this)
            onExitFinished: manager._onPopupExitFinished(this)
        }

    }

    property Connections notificationConnections

    notificationConnections: Connections {
        function onVisibleNotificationsChanged() {
            manager._sync(NotificationService.visibleNotifications);
        }

        target: NotificationService
    }

    property Timer sweeper

    sweeper: Timer {
        interval: 2000
        running: false // Not running by default
        repeat: true
        onTriggered: {
            let toRemove = [];
            for (let p of popupWindows) {
                if (!p) {
                    toRemove.push(p);
                    continue;
                }
                const isZombie = p.status === Component.Null || (!p.visible && !p.exiting) || (!p.notificationData && !p._isDestroying) || (!p.hasValidData && !p._isDestroying);
                if (isZombie) {
                    
                    toRemove.push(p);
                    if (p.forceExit) {
                        p.forceExit();
                    } else if (p.destroy) {
                        try {
                            p.destroy();
                        } catch (e) {
                            
                        }
                    }
                }
            }
            if (toRemove.length > 0) {
                for (let zombie of toRemove) {
                    const i = popupWindows.indexOf(zombie);
                    if (i !== -1)
                        popupWindows.splice(i, 1);

                }
                popupWindows = popupWindows.slice();
                const survivors = _active().sort((a, b) => {
                    return a.screenY - b.screenY;
                });
                for (let k = 0; k < survivors.length; ++k) {
                    survivors[k].screenY = topMargin + k * baseNotificationHeight;
                }
            }
            if (popupWindows.length === 0)
                sweeper.stop();

        }
    }

    function _hasWindowFor(w) {
        return popupWindows.some((p) => {
            return p && p.notificationData === w && !p._isDestroying && p.status !== Component.Null;
        });
    }

    function _isValidWindow(p) {
        return p && p.status !== Component.Null && !p._isDestroying && p.hasValidData;
    }

    function _sync(newWrappers) {
        for (let w of newWrappers) {
            if (w && !_hasWindowFor(w))
                insertNewestAtTop(w);

        }
        for (let p of popupWindows.slice()) {
            if (!_isValidWindow(p))
                continue;

            if (p.notificationData && newWrappers.indexOf(p.notificationData) === -1 && !p.exiting) {
                p.notificationData.removedByLimit = true;
                p.notificationData.popup = false;
            }
        }
    }

    function insertNewestAtTop(wrapper) {
        if (!wrapper) {
            
            return ;
        }
        for (let p of popupWindows) {
            if (!_isValidWindow(p))
                continue;

            if (p.exiting)
                continue;

            p.screenY = p.screenY + baseNotificationHeight;
        }
        const notificationId = wrapper && wrapper.notification ? wrapper.notification.id : "";
        const win = popupComponent.createObject(null, {
            "notificationData": wrapper,
            "notificationId": notificationId,
            "screenY": topMargin,
            "screen": manager.modelData
        });
        if (!win) {
            
            return ;
        }
        if (!win.hasValidData) {
            
            win.destroy();
            return ;
        }
        popupWindows.push(win);
        if (!sweeper.running)
            sweeper.start();

        _maybeStartOverflow();
    }

    function _active() {
        return popupWindows.filter((p) => {
            return _isValidWindow(p) && p.notificationData && p.notificationData.popup && !p.exiting;
        });
    }

    function _bottom() {
        let b = null, maxY = -1;
        for (let p of _active()) {
            if (p.screenY > maxY) {
                maxY = p.screenY;
                b = p;
            }
        }
        return b;
    }

    function _maybeStartOverflow() {
        const activeWindows = _active();
        if (activeWindows.length <= maxTargetNotifications + 1)
            return ;

        const b = _bottom();
        if (b && !b.exiting) {
            b.notificationData.removedByLimit = true;
            b.notificationData.popup = false;
        }
    }

    function _onPopupEntered(p) {
        if (_isValidWindow(p))
            _maybeStartOverflow();

    }

    function _onPopupExitFinished(p) {
        if (!p)
            return ;

        const windowId = p.toString();
        if (destroyingWindows.has(windowId))
            return ;

        destroyingWindows.add(windowId);
        const i = popupWindows.indexOf(p);
        if (i !== -1) {
            popupWindows.splice(i, 1);
            popupWindows = popupWindows.slice();
        }
        if (NotificationService.releaseWrapper && p.notificationData)
            NotificationService.releaseWrapper(p.notificationData);

        Qt.callLater(() => {
            if (p && p.destroy) {
                try {
                    p.destroy();
                } catch (e) {
                    
                }
            }
            Qt.callLater(() => {
                destroyingWindows.delete(windowId);
            });
        });
        const survivors = _active().sort((a, b) => {
            return a.screenY - b.screenY;
        });
        for (let k = 0; k < survivors.length; ++k) {
            survivors[k].screenY = topMargin + k * baseNotificationHeight;
        }
        _maybeStartOverflow();
    }

    function cleanupAllWindows() {
        sweeper.stop();
        for (let p of popupWindows.slice()) {
            if (p) {
                try {
                    if (p.forceExit)
                        p.forceExit();
                    else if (p.destroy)
                        p.destroy();
                } catch (e) {
                    
                }
            }
        }
        popupWindows = [];
        destroyingWindows.clear();
    }

    onPopupWindowsChanged: {
        if (popupWindows.length > 0 && !sweeper.running)
            sweeper.start();
        else if (popupWindows.length === 0 && sweeper.running)
            sweeper.stop();
    }
}