import QtQuick 2.9
import QtQuick.Controls 2.2
import QtQuick.Layouts 1.3
import QtQuick.Window 2.2

import ComputerManager 1.0
import AutoUpdateChecker 1.0
import StreamingPreferences 1.0
import SystemProperties 1.0
import SdlGamepadKeyNavigation 1.0

ApplicationWindow {
    property bool pollingActive: false

    // Set by SettingsView to force the back operation to pop all
    // pages except the initial view. This is required when doing
    // a retranslate() because AppView breaks for some reason.
    property bool clearOnBack: false

    id: window
    visible: true
    width: 1280
    height: 600

    visibility: {
        if (SystemProperties.hasDesktopEnvironment) {
            if (StreamingPreferences.uiDisplayMode == StreamingPreferences.UI_WINDOWED) return "Windowed"
            else if (StreamingPreferences.uiDisplayMode == StreamingPreferences.UI_MAXIMIZED) return "Maximized"
            else if (StreamingPreferences.uiDisplayMode == StreamingPreferences.UI_FULLSCREEN) return "FullScreen"
        } else {
            return "FullScreen"
        }
    }
  
    // This configures the maximum width of the singleton attached QML ToolTip. If left unconstrained,
    // it will never insert a line break and just extend on forever.
    ToolTip.toolTip.contentWidth: ToolTip.toolTip.implicitContentWidth < 400 ? ToolTip.toolTip.implicitContentWidth : 400

    function goBack() {
        if (clearOnBack) {
            // Pop all items except the first one
            stackView.pop(null)
            clearOnBack = false
        }
        else {
            stackView.pop()
        }
    }

    StackView {
        id: stackView
        initialItem: initialView
        anchors.fill: parent
        focus: true

        onCurrentItemChanged: {
            // Ensure focus travels to the next view when going back
            if (currentItem) {
                currentItem.forceActiveFocus()
            }
        }

        Keys.onEscapePressed: {
            if (depth > 1) {
                goBack()
            }
            else {
                quitConfirmationDialog.open()
            }
        }

        Keys.onBackPressed: {
            if (depth > 1) {
                goBack()
            }
            else {
                quitConfirmationDialog.open()
            }
        }

        Keys.onMenuPressed: {
            settingsButton.clicked()
        }

        // This is a keypress we've reserved for letting the
        // SdlGamepadKeyNavigation object tell us to show settings
        // when Menu is consumed by a focused control.
        Keys.onHangupPressed: {
            settingsButton.clicked()
        }
    }

    // This timer keeps us polling for 5 minutes of inactivity
    // to allow the user to work with Moonlight on a second display
    // while dealing with configuration issues. This will ensure
    // machines come online even if the input focus isn't on Moonlight.
    Timer {
        id: inactivityTimer
        interval: 5 * 60000
        onTriggered: {
            if (!active && pollingActive) {
                ComputerManager.stopPollingAsync()
                pollingActive = false
            }
        }
    }

    onVisibleChanged: {
        // When we become invisible while streaming is going on,
        // stop polling immediately.
        if (!visible) {
            inactivityTimer.stop()

            if (pollingActive) {
                ComputerManager.stopPollingAsync()
                pollingActive = false
            }
        }
        else if (active) {
            // When we become visible and active again, start polling
            inactivityTimer.stop()

            // Restart polling if it was stopped
            if (!pollingActive) {
                ComputerManager.startPolling()
                pollingActive = true
            }
        }
    }

    onActiveChanged: {
        if (active) {
            // Stop the inactivity timer
            inactivityTimer.stop()

            // Restart polling if it was stopped
            if (!pollingActive) {
                ComputerManager.startPolling()
                pollingActive = true
            }
        }
        else {
            // Start the inactivity timer to stop polling
            // if focus does not return within a few minutes.
            inactivityTimer.restart()
        }
    }

    property bool initialized: false

    // BUG: Using onAfterSynchronizing: here causes very strange
    // failures on Linux. Many shaders fail to compile and we
    // eventually segfault deep inside the Qt OpenGL code.
    onAfterRendering: {
        // We use this callback to trigger dialog display because
        // it only happens once the window is fully constructed.
        // Doing it earlier can lead to the dialog appearing behind
        // the window or otherwise without input focus.
        if (!initialized) {
            // Set initialized before calling anything else, because
            // pumping the event loop can cause us to get another
            // onAfterRendering call and potentially reenter this code.
            initialized = true;

            if (SystemProperties.isWow64) {
                wow64Dialog.open()
            }
            else if (!SystemProperties.hasHardwareAcceleration) {
                if (SystemProperties.isRunningXWayland) {
                    xWaylandDialog.open()
                }
                else {
                    noHwDecoderDialog.open()
                }
            }

            if (SystemProperties.unmappedGamepads) {
                unmappedGamepadDialog.unmappedGamepads = SystemProperties.unmappedGamepads
                unmappedGamepadDialog.open()
            }
        }
    }

    // Workaround for lack of instanceof in Qt 5.9.
    //
    // Based on https://stackoverflow.com/questions/13923794/how-to-do-a-is-a-typeof-or-instanceof-in-qml
    function qmltypeof(obj, className) { // QtObject, string -> bool
        // className plus "(" is the class instance without modification
        // className plus "_QML" is the class instance with user-defined properties
        var str = obj.toString();
        return str.startsWith(className + "(") || str.startsWith(className + "_QML");
    }

    function navigateTo(url, objectType)
    {
        var existingItem = stackView.find(function(item, index) {
            return qmltypeof(item, objectType)
        })

        if (existingItem !== null) {
            // Pop to the existing item
            stackView.pop(existingItem)
        }
        else {
            // Create a new item
            stackView.push(url)
        }
    }

    header: ToolBar {
        id: toolBar
        height: 60
        anchors.topMargin: 5
        anchors.bottomMargin: 5

        Label {
            id: titleLabel
            visible: toolBar.width > 700
            anchors.fill: parent
            text: stackView.currentItem.objectName
            font.pointSize: 20
            elide: Label.ElideRight
            horizontalAlignment: Qt.AlignHCenter
            verticalAlignment: Qt.AlignVCenter
        }

        RowLayout {
            spacing: 10
            anchors.leftMargin: 10
            anchors.rightMargin: 10
            anchors.fill: parent

            NavigableToolButton {
                // Only make the button visible if the user has navigated somewhere.
                visible: stackView.depth > 1

                iconSource: "qrc:/res/arrow_left.svg"

                onClicked: goBack()

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }
            }

            // This label will appear when the window gets too small and
            // we need to ensure the toolbar controls don't collide
            Label {
                id: titleRowLabel
                font.pointSize: titleLabel.font.pointSize
                elide: Label.ElideRight
                horizontalAlignment: Qt.AlignHCenter
                verticalAlignment: Qt.AlignVCenter
                Layout.fillWidth: true

                // We need this label to always be visible so it can occupy
                // the remaining space in the RowLayout. To "hide" it, we
                // just set the text to empty string.
                text: !titleLabel.visible ? stackView.currentItem.objectName : ""
            }

            Label {
                id: versionLabel
                visible: qmltypeof(stackView.currentItem, "SettingsView")
                text: qsTr("Version %1").arg(SystemProperties.versionString)
                font.pointSize: 12
                horizontalAlignment: Qt.AlignRight
                verticalAlignment: Qt.AlignVCenter
            }

            NavigableToolButton {
                id: discordButton
                visible: SystemProperties.hasBrowser &&
                         qmltypeof(stackView.currentItem, "SettingsView")

                iconSource: "qrc:/res/Discord-Logo-White.svg"

                ToolTip.delay: 1000
                ToolTip.timeout: 3000
                ToolTip.visible: hovered
                ToolTip.text: qsTr("Join our community on Discord")

                // TODO need to make sure browser is brought to foreground.
                onClicked: Qt.openUrlExternally("https://moonlight-stream.org/discord");

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }
            }

            NavigableToolButton {
                id: addPcButton
                visible: qmltypeof(stackView.currentItem, "PcView")

                iconSource:  "qrc:/res/ic_add_to_queue_white_48px.svg"

                ToolTip.delay: 1000
                ToolTip.timeout: 3000
                ToolTip.visible: hovered
                ToolTip.text: qsTr("Add PC manually") + (newPcShortcut.nativeText ? (" ("+newPcShortcut.nativeText+")") : "")

                Shortcut {
                    id: newPcShortcut
                    sequence: StandardKey.New
                    onActivated: addPcButton.clicked()
                }

                onClicked: {
                    addPcDialog.open()
                }

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }
            }

            NavigableToolButton {
                property string browserUrl: ""

                id: updateButton

                iconSource: "qrc:/res/update.svg"

                ToolTip.delay: 1000
                ToolTip.timeout: 3000
                ToolTip.visible: hovered || visible

                // Invisible until we get a callback notifying us that
                // an update is available
                visible: false

                onClicked: {
                    if (SystemProperties.hasBrowser) {
                        Qt.openUrlExternally(browserUrl);
                    }
                }

                function updateAvailable(version, url)
                {
                    ToolTip.text = qsTr("Update available for Moonlight: Version %1").arg(version)
                    updateButton.browserUrl = url
                    updateButton.visible = true
                }

                Component.onCompleted: {
                    AutoUpdateChecker.onUpdateAvailable.connect(updateAvailable)
                    AutoUpdateChecker.start()
                }

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }
            }

            NavigableToolButton {
                id: helpButton
                visible: SystemProperties.hasBrowser

                iconSource: "qrc:/res/question_mark.svg"

                ToolTip.delay: 1000
                ToolTip.timeout: 3000
                ToolTip.visible: hovered
                ToolTip.text: qsTr("Help") + (helpShortcut.nativeText ? (" ("+helpShortcut.nativeText+")") : "")

                Shortcut {
                    id: helpShortcut
                    sequence: StandardKey.HelpContents
                    onActivated: helpButton.clicked()
                }

                // TODO need to make sure browser is brought to foreground.
                onClicked: Qt.openUrlExternally("https://github.com/moonlight-stream/moonlight-docs/wiki/Setup-Guide");

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }
            }

            NavigableToolButton {
                // TODO: Implement gamepad mapping then unhide this button
                visible: false

                ToolTip.delay: 1000
                ToolTip.timeout: 3000
                ToolTip.visible: hovered
                ToolTip.text: qsTr("Gamepad Mapper")

                iconSource: "qrc:/res/ic_videogame_asset_white_48px.svg"

                onClicked: navigateTo("qrc:/gui/GamepadMapper.qml", "GamepadMapper")

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }
            }

            NavigableToolButton {
                id: settingsButton

                iconSource:  "qrc:/res/settings.svg"

                onClicked: navigateTo("qrc:/gui/SettingsView.qml", "SettingsView")

                Keys.onDownPressed: {
                    stackView.currentItem.forceActiveFocus(Qt.TabFocus)
                }

                Shortcut {
                    id: settingsShortcut
                    sequence: StandardKey.Preferences
                    onActivated: settingsButton.clicked()
                }

                ToolTip.delay: 1000
                ToolTip.timeout: 3000
                ToolTip.visible: hovered
                ToolTip.text: qsTr("Settings") + (settingsShortcut.nativeText ? (" ("+settingsShortcut.nativeText+")") : "")
            }
        }
    }

    ErrorMessageDialog {
        id: noHwDecoderDialog
        text: qsTr("No functioning hardware accelerated video decoder was detected by Moonlight. " +
                   "Your streaming performance may be severely degraded in this configuration.")
        helpText: qsTr("Click the Help button for more information on solving this problem.")
        helpUrl: "https://github.com/moonlight-stream/moonlight-docs/wiki/Fixing-Hardware-Decoding-Problems"
    }

    ErrorMessageDialog {
        id: xWaylandDialog
        text: qsTr("Hardware acceleration doesn't work on XWayland. Continuing on XWayland may result in poor streaming performance. " +
                   "Try running with QT_QPA_PLATFORM=wayland or switch to X11.")
        helpText: qsTr("Click the Help button for more information.")
        helpUrl: "https://github.com/moonlight-stream/moonlight-docs/wiki/Fixing-Hardware-Decoding-Problems"
    }

    NavigableMessageDialog {
        id: wow64Dialog
        standardButtons: Dialog.Ok | Dialog.Cancel
        text: qsTr("This version of Moonlight isn't optimized for your PC. Please download the '%1' version of Moonlight for the best streaming performance.").arg(SystemProperties.friendlyNativeArchName)
        onAccepted: {
            Qt.openUrlExternally("https://github.com/moonlight-stream/moonlight-qt/releases");
        }
    }

    ErrorMessageDialog {
        id: unmappedGamepadDialog
        property string unmappedGamepads : ""
        text: qsTr("Moonlight detected gamepads without a mapping:") + "\n" + unmappedGamepads
        helpTextSeparator: "\n\n"
        helpText: qsTr("Click the Help button for information on how to map your gamepads.")
        helpUrl: "https://github.com/moonlight-stream/moonlight-docs/wiki/Gamepad-Mapping"
    }

    // This dialog appears when quitting via keyboard or gamepad button
    NavigableMessageDialog {
        id: quitConfirmationDialog
        standardButtons: Dialog.Yes | Dialog.No
        text: qsTr("Are you sure you want to quit?")
        // For keyboard/gamepad navigation
        onAccepted: Qt.quit()
    }

    // HACK: This belongs in StreamSegue but keeping a dialog around after the parent
    // dies can trigger bugs in Qt 5.12 that cause the app to crash. For now, we will
    // host this dialog in a QML component that is never destroyed.
    //
    // To repro: Start a stream, cut the network connection to trigger the "Connection
    // terminated" dialog, wait until the app grid times out back to the PC grid, then
    // try to dismiss the dialog.
    ErrorMessageDialog {
        id: streamSegueErrorDialog

        property bool quitAfter: false

        onClosed: {
            if (quitAfter) {
                Qt.quit()
            }

            // StreamSegue assumes its dialog will be re-created each time we
            // start streaming, so fake it by wiping out the text each time.
            text = ""
        }
    }

    NavigableDialog {
        id: addPcDialog
        property string label: qsTr("Enter the IP address of your GameStream PC:")

        standardButtons: Dialog.Ok | Dialog.Cancel

        onOpened: {
            // Force keyboard focus on the textbox so keyboard navigation works
            editText.forceActiveFocus()
        }

        onClosed: {
            editText.clear()
        }

        onAccepted: {
            if (editText.text) {
                ComputerManager.addNewHostManually(editText.text.trim())
            }
        }

        ColumnLayout {
            Label {
                text: addPcDialog.label
                font.bold: true
            }

            TextField {
                id: editText
                Layout.fillWidth: true
                focus: true

                Keys.onReturnPressed: {
                    addPcDialog.accept()
                }

                Keys.onEnterPressed: {
                    addPcDialog.accept()
                }
            }
        }
    }
}