/*
 *   SPDX-FileCopyrightText: 2015 Marco Martin <notmart@gmail.com>
 *   SPDX-FileCopyrightText: 2021 Devin Lin <devin@kde.org>
 *
 *   SPDX-License-Identifier: GPL-2.0-or-later
 */

import QtQuick 2.15
import QtQuick.Layouts 1.1
import QtQuick.Window 2.2
import QtQuick.Controls 2.2 as QQC2

import org.kde.taskmanager 0.1 as TaskManager
import org.kde.plasma.core 2.0 as PlasmaCore
import org.kde.plasma.components 3.0 as PlasmaComponents
import org.kde.plasma.private.mobileshell 1.0 as MobileShell

Item {
    id: delegate

    required property var taskSwitcher
    
    required property var model
    required property var displaysModel

    required property real previewHeight
    required property real previewWidth
    
    readonly property point taskScreenPoint: (model && model.ScreenGeometry) ? Qt.point(model.ScreenGeometry.x, model.ScreenGeometry.y) : Qt.point(0, 0)
    readonly property real dragOffset: -control.y
    
    property bool showHeader: true
    property real darken: 0
    
    opacity: 1 - dragOffset / taskSwitcher.height
    
//BEGIN functions
    function syncDelegateGeometry() {
        let pos = pipeWireLoader.mapToItem(delegate, 0, 0);
        if (taskSwitcher.visible) {
            tasksModel.requestPublishDelegateGeometry(tasksModel.index(model.index, 0), Qt.rect(pos.x, pos.y, pipeWireLoader.width, pipeWireLoader.height), pipeWireLoader);
        }
    }
    
    function closeApp() {
        tasksModel.requestClose(tasksModel.index(model.index, 0));
    }
    
    function activateApp() {
        taskSwitcherState.wasInActiveTask = false;
        taskSwitcher.activateWindow(model.index);
    }
//END functions
    
    Component.onCompleted: syncDelegateGeometry();
    
    Connections {
        target: taskSwitcher
        function onVisibleChanged() {
            syncDelegateGeometry();
        }
    }
    
    MouseArea {
        id: control
        width: parent.width
        height: parent.height
        enabled: !taskSwitcher.taskSwitcherState.currentlyBeingOpened
        
        // set cursor shape here, since taphandler seems to not be able to do it
        cursorShape: Qt.PointingHandCursor
        
        property bool movingUp: false
        property real oldY: y
        onYChanged: {
            movingUp = y < oldY;
            oldY = y;
        }
        
        // drag up gesture
        DragHandler {
            id: dragHandler
            target: parent
            
            enabled: !taskSwitcher.taskSwitcherState.currentlyBeingOpened
            
            yAxis.enabled: true
            xAxis.enabled: false
            yAxis.maximum: 0
            
            // y > 0 - dragging down (opening the app)
            // y < 0 - dragging up (dismissing the app)
            onActiveChanged: {
                yAnimator.stop();
                
                if (control.movingUp && parent.y < -PlasmaCore.Units.gridUnit * 2) {
                    yAnimator.to = -root.height;
                } else {
                    yAnimator.to = 0;
                }
                yAnimator.start();
            }
        }
        
        // if the app doesn't close within a certain time, drag it back
        Timer {
            id: uncloseTimer
            interval: 3000
            onTriggered: {
                yAnimator.to = 0;
                yAnimator.restart();
            }
        }
        
        NumberAnimation on y {
            id: yAnimator
            running: !dragHandler.active
            duration: PlasmaCore.Units.longDuration
            easing.type: Easing.InOutQuad
            to: 0
            onFinished: {
                if (to != 0) { // close app
                    delegate.closeApp();
                    uncloseTimer.start();
                }
            }
        }

        // application
        ColumnLayout {
            id: column
            anchors.fill: parent
            spacing: 0
            
            // header
            RowLayout {
                id: appHeader
                Layout.fillWidth: true
                Layout.fillHeight: true
                Layout.minimumHeight: column.height - appView.height
                spacing: PlasmaCore.Units.smallSpacing * 2
                opacity: delegate.showHeader ? 1 : 0
                
                Behavior on opacity {
                    NumberAnimation { duration: PlasmaCore.Units.shortDuration }
                }
                
                PlasmaCore.IconItem {
                    Layout.preferredHeight: PlasmaCore.Units.iconSizes.smallMedium
                    Layout.preferredWidth: PlasmaCore.Units.iconSizes.smallMedium
                    Layout.alignment: Qt.AlignVCenter
                    usesPlasmaTheme: false
                    source: model.decoration
                }
                
                PlasmaComponents.Label {
                    Layout.fillWidth: true
                    Layout.alignment: Qt.AlignVCenter
                    elide: Text.ElideRight
                    text: model.AppName
                    color: "white"
                }
                
                Repeater {
                    id: rep
                    model: displaysModel
                    delegate: PlasmaComponents.ToolButton {
                        Layout.alignment: Qt.AlignVCenter
                        text: model.modelName
                        visible: model.position !== delegate.taskScreenPoint
                        display: rep.count < 3 ? QQC2.Button.IconOnly : QQC2.Button.TextBesideIcon
                        icon.name: "tv" //TODO provide a more adequate icon

                        onClicked: {
                            displaysModel.sendWindowToOutput(delegate.model.WinIdList[0], model.output)
                        }
                    }
                }
                
                PlasmaComponents.ToolButton {
                    Layout.alignment: Qt.AlignVCenter
                    z: 99
                    icon.name: "window-close"
                    icon.width: PlasmaCore.Units.iconSizes.smallMedium
                    icon.height: PlasmaCore.Units.iconSizes.smallMedium
                    onClicked: delegate.closeApp()
                }
            }
            
            // app preview
            Rectangle {
                id: appView
                Layout.preferredWidth: delegate.previewWidth
                Layout.preferredHeight: delegate.previewHeight
                Layout.maximumWidth: delegate.previewWidth
                Layout.maximumHeight: delegate.previewHeight
                
                color: PlasmaCore.Theme.backgroundColor
                clip: true
                
                // scale animation on press
                property real zoomScale: (MobileShell.MobileShellSettings.animationsEnabled && tapHandler.pressed) ? 0.9 : 1
                Behavior on zoomScale {
                    NumberAnimation {
                        duration: 200
                        easing.type: Easing.OutExpo
                    }
                }
                
                transform: Scale { 
                    origin.x: appView.width / 2; 
                    origin.y: appView.height / 2; 
                    xScale: appView.zoomScale
                    yScale: appView.zoomScale
                }
                
                Item {
                    id: item
                    anchors.fill: parent
                    
                    // app icon (behind window preview in-case it doesn't load)
                    TaskIcon {
                        // decrease the opacity faster
                        opacity: pipeWireLoader.item && pipeWireLoader.item.uuid ? 0 : delegate.opacity
                        anchors.centerIn: parent
                    }

                    // attempt to load window preview
                    Loader {
                        id: pipeWireLoader
                        active: taskSwitcher.visible || taskSwitcher.tasksModel.taskReorderingEnabled
                        anchors.fill: parent
                        source: Qt.resolvedUrl("./Thumbnail.qml")
                        
                        asynchronous: true
                        
                        onLoaded: this.item.refresh()
                    }
                    
                    // darken effect
                    Rectangle {
                        anchors.fill: parent
                        color: "black"
                        opacity: delegate.darken
                    }
                    
                    TapHandler {
                        id: tapHandler
                        enabled: !taskSwitcher.taskSwitcherState.currentlyBeingOpened
                        onTapped: delegate.activateApp()
                    }
                }
            }
        }
    }
}