// Copyright (c) 2022 Proton AG
//
// This file is part of Proton Mail Bridge.
//
// Proton Mail Bridge is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Proton Mail Bridge is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Proton Mail Bridge. If not, see <https://www.gnu.org/licenses/>.

import QtQml 2.12
import QtQuick 2.12
import QtQuick.Window 2.12
import QtQuick.Controls 2.12
import QtQuick.Controls.impl 2.12
import QtQuick.Templates 2.12 as T

T.ApplicationWindow {
    id: root

    property ColorScheme colorScheme

    // popup priority based on types
    enum PopupType {
        Banner = 0,
        Dialog = 1
    }

    // contains currently visible popup
    property var popupVisible: null

    // list of all popups within ApplicationWindow
    property ListModel popups: ListModel {
        // overriding get method to ignore any role and return directly object itself
        function get(row) {
            if (row < 0 || row >= count) {
                return undefined
            }
            return data(index(row, 0), Qt.DisplayRole)
        }

        onRowsInserted: {
            for (var i = first; i <= last; i++) {
                var obj = popups.get(i)
                obj.onShouldShowChanged.connect( root.processPopups )
            }

            processPopups()
        }

        onRowsAboutToBeRemoved: {
            for (var i = first; i <= last; i++ ) {
                var obj = popups.get(i)
                obj.onShouldShowChanged.disconnect( root.processPopups )

                // if currently visible popup was removed
                if (root.popupVisible === obj) {
                    root.popupVisible.visible = false
                    root.popupVisible = null
                }
            }

            processPopups()
        }
    }

    function processPopups() {
        if ((root.popupVisible) && (!root.popupVisible.shouldShow)) {
            root.popupVisible.visible = false
        }

        var topmost = null
        for (var i = 0; i < popups.count; i++) {
            var obj = popups.get(i)

            if (obj.shouldShow === false) {
                continue
            }

            if (topmost && (topmost.popupType > obj.popupType)) {
                continue
            }

            if (topmost && (topmost.popupType === obj.popupType) && (topmost.occurred > obj.occurred)) {
                continue
            }

            topmost = obj
        }

        if (root.popupVisible !== topmost) {
            if (root.popupVisible) {
                root.popupVisible.visible = false
            }
            root.popupVisible = topmost
        }

        if (!root.popupVisible) {
            return
        }

        root.popupVisible.visible = true
    }

    Connections {
        target: root.popupVisible

        onVisibleChanged: {
            if (root.popupVisible.visible) {
                return
            }

            root.popupVisible = null
            root.processPopups()
        }
    }

    color: root.colorScheme.background_norm

    overlay.modal: Rectangle {
        color: root.colorScheme.backdrop_norm
    }

    overlay.modeless: Rectangle {
        color: "transparent"
    }
}