/*
 *  SPDX-FileCopyrightText: 2012 Marco Martin <mart@kde.org>
 *
 *  SPDX-License-Identifier: LGPL-2.0-or-later
 */

import QtQuick
import QtQuick.Templates as T
import QtQuick.Controls as QQC2
import org.kde.kirigami as Kirigami
import "private" as KTP

/**
 * Overlay Drawers are used to expose additional UI elements needed for
 * small secondary tasks for which the main UI elements are not needed.
 * For example in Okular Mobile, an Overlay Drawer is used to display
 * thumbnails of all pages within a document along with a search field.
 * This is used for the distinct task of navigating to another page.
 *
 * @inherit QtQuick.Controls.Drawer
 */
T.Drawer {
    id: root

//BEGIN properties
    /**
     * @brief This property tells whether the drawer is open and visible.
     *
     * default: ``false``
     */
    property bool drawerOpen: false

    /**
     * @brief This property tells whether the drawer is in a state between open
     * and closed.
     *
     * The drawer is visible but not completely open. This is usually the case when
     * the user is dragging the drawer from a screen edge, so the user is "peeking"
     * at what's in the drawer.
     *
     * default: ``false``
     */
    property bool peeking: false

    /**
     * @brief This property tells whether the drawer is currently opening or closing itself.
     */
    readonly property bool animating : enterAnimation.animating || exitAnimation.animating || positionResetAnim.running

    /**
     * @brief This property holds whether the drawer can be collapsed to a
     * very thin, usually icon only sidebar.
     *
     * Only modal drawers are collapsible. Collapsible is not supported in
     * the mobile mode.
     *
     * @since 2.5
     */
    property bool collapsible: false

    /**
     * @brief This property tells whether the drawer is collapsed to a
     * very thin sidebar, usually icon only.
     *
     * When true, the drawer will be collapsed to a very thin sidebar,
     * usually icon only.
     *
     * default: ``false``
     *
     * @see collapsible Only collapsible drawers can be collapsed.
     */
    property bool collapsed: false

    /**
     * @brief This property holds the size of the collapsed drawer.
     *
     * For vertical drawers this will be the width of the drawer and for horizontal
     * drawers this will be the height of the drawer.
     *
     * default: ``Units.iconSizes.medium``, just enough to accommodate medium sized icons
     */
    property int collapsedSize: Kirigami.Units.iconSizes.medium

    /**
     * @brief This property holds the options for handle's open icon.
     *
     * This is a grouped property with following components:
     *
     * * ``source: var``: The name of a freedesktop-compatible icon.
     * * ``color: color``: An optional tint color for the icon.
     *
     * If no custom icon is set, a menu icon is shown for the application globalDrawer
     * and an overflow menu icon is shown for the contextDrawer.
     * That's the default for the GlobalDrawer and ContextDrawer components respectively.
     *
     * For OverlayDrawer the default is view-right-close or view-left-close depending on
     * the drawer location
     *
     * @since 2.5
     */
    readonly property KTP.IconPropertiesGroup handleOpenIcon: KTP.IconPropertiesGroup {
        source: root.edge === Qt.RightEdge ? "view-right-close" : "view-left-close"
    }

    /**
     * @brief This property holds the options for the handle's close icon.
     *
     * This is a grouped property with the following components:
     * * ``source: var``: The name of a freedesktop-compatible icon.
     * * ``color: color``: An optional tint color for the icon.
     *
     * If no custom icon is set, an X icon is shown,
     * which will morph into the Menu or overflow icons.
     *
     * For OverlayDrawer the default is view-right-new or view-left-new depending on
     * the drawer location.
     *
     * @since 2.5
     */
    property KTP.IconPropertiesGroup handleClosedIcon: KTP.IconPropertiesGroup {
        source: root.edge === Qt.RightEdge ? "view-right-new" : "view-left-new"
    }

    /**
     * @brief This property holds the tooltip displayed when the drawer is open.
     * @since 2.15
     */
    property string handleOpenToolTip: qsTr("Close drawer")

    /**
     * @brief This property holds the tooltip displayed when the drawer is closed.
     * @since 2.15
     */
    property string handleClosedToolTip: qsTr("Open drawer")

    /**
     * @brief This property holds whether the handle is visible, to make opening the
     * drawer easier.
     *
     * Currently supported only on left and right drawers.
     */
    property bool handleVisible: {
        if (typeof applicationWindow === "function") {
            const w = applicationWindow();
            if (w) {
                return w.controlsVisible;
            }
        }
        // For a generic-purpose OverlayDrawer its handle is visible by default
        return true;
    }

    /**
     * @brief Readonly property that points to the item that will act as a physical
     * handle for the Drawer.
     * @property MouseArea handle
     **/
    readonly property Item handle: KTP.DrawerHandle {
        drawer: root
    }
//END properties

    interactive: modal

    z: Kirigami.OverlayZStacking.z

    Kirigami.Theme.inherit: false
    Kirigami.Theme.colorSet: modal ? Kirigami.Theme.View : Kirigami.Theme.Window
    Kirigami.Theme.onColorSetChanged: {
        contentItem.Kirigami.Theme.colorSet = Kirigami.Theme.colorSet
        background.Kirigami.Theme.colorSet = Kirigami.Theme.colorSet
    }

//BEGIN reassign properties
    //default paddings
    leftPadding: Kirigami.Units.smallSpacing
    topPadding: Kirigami.Units.smallSpacing
    rightPadding: Kirigami.Units.smallSpacing
    bottomPadding: Kirigami.Units.smallSpacing

    y: modal ? 0 : ((T.ApplicationWindow.menuBar ? T.ApplicationWindow.menuBar.height : 0) + (T.ApplicationWindow.header ? T.ApplicationWindow.header.height : 0))

    height: parent && (root.edge === Qt.LeftEdge || root.edge === Qt.RightEdge) ? (modal ? parent.height : (parent.height - y - (T.ApplicationWindow.footer ? T.ApplicationWindow.footer.height : 0))) : implicitHeight

    parent: modal || edge === Qt.LeftEdge || edge === Qt.RightEdge ? T.ApplicationWindow.overlay : T.ApplicationWindow.contentItem

    edge: Qt.LeftEdge
    modal: true
    dim: modal
    QQC2.Overlay.modal: Rectangle {
        color: Qt.rgba(0, 0, 0, 0.35)
    }

    dragMargin: enabled && (edge === Qt.LeftEdge || edge === Qt.RightEdge) ? Math.min(Kirigami.Units.gridUnit, Qt.styleHints.startDragDistance) : 0

    contentWidth: contentItem.implicitWidth || (contentChildren.length === 1 ? contentChildren[0].implicitWidth : 0)
    contentHeight: contentItem.implicitHeight || (contentChildren.length === 1 ? contentChildren[0].implicitHeight : 0)

    implicitWidth: contentWidth + leftPadding + rightPadding
    implicitHeight: contentHeight + topPadding + bottomPadding

    enter: Transition {
        SequentialAnimation {
            id: enterAnimation
            /* NOTE: why this? the running status of the enter transition is not relaible and
             * the SmoothedAnimation is always marked as non running,
             * so the only way to get to a reliable animating status is with this
             */
            property bool animating
            ScriptAction {
                script: {
                    enterAnimation.animating = true
                    // on non modal dialog we don't want drawers in the overlay
                    if (!root.modal) {
                        root.background.parent.parent = applicationWindow().overlay.parent
                    }
                }
            }
            SmoothedAnimation {
                velocity: 5
            }
            ScriptAction {
                script: enterAnimation.animating = false
            }
        }
    }

    exit: Transition {
        SequentialAnimation {
            id: exitAnimation
            property bool animating
            ScriptAction {
                script: exitAnimation.animating = true
            }
            SmoothedAnimation {
                velocity: 5
            }
            ScriptAction {
                script: exitAnimation.animating = false
            }
        }
    }
//END reassign properties


//BEGIN signal handlers
    onCollapsedChanged: {
        if (Kirigami.Settings.isMobile) {
            collapsed = false;
        }
        if (!__internal.completed) {
            return;
        }
        if ((!collapsible || modal) && collapsed) {
            collapsed = true;
        }
    }
    onCollapsibleChanged: {
        if (Kirigami.Settings.isMobile) {
            collapsible = false;
        }
        if (!__internal.completed) {
            return;
        }
        if (!collapsible) {
            collapsed = false;
        } else if (modal) {
            collapsible = false;
        }
    }
    onModalChanged: {
        if (!__internal.completed) {
            return;
        }
        if (modal) {
            collapsible = false;
        }
    }

    onPositionChanged: {
        if (peeking) {
            visible = true
        }
    }
    onVisibleChanged: {
        if (peeking) {
            visible = true
        } else {
            drawerOpen = visible;
        }
    }
    onPeekingChanged:  {
        if (peeking) {
            root.enter.enabled = false;
            root.exit.enabled = false;
        } else {
            drawerOpen = position > 0.5 ? 1 : 0;
            positionResetAnim.running = true
            root.enter.enabled = true;
            root.exit.enabled = true;
        }
    }
    onDrawerOpenChanged: {
        // sync this property only when the component is properly loaded
        if (!__internal.completed) {
            return;
        }
        positionResetAnim.running = false;
        if (drawerOpen) {
            open();
        } else {
            close();
        }
        Qt.callLater(() => root.handle.displayToolTip = true)
    }

    Component.onCompleted: {
        // if defined as drawerOpen by default in QML, don't animate
        if (root.drawerOpen) {
            root.enter.enabled = false;
            root.visible = true;
            root.position = 1;
            root.enter.enabled = true;
        }
        __internal.completed = true;
        contentItem.Kirigami.Theme.colorSet = Kirigami.Theme.colorSet;
        background.Kirigami.Theme.colorSet = Kirigami.Theme.colorSet;
    }
//END signal handlers

    // this is as hidden as it can get here
    property QtObject __internal: QtObject {
        //here in order to not be accessible from outside
        property bool completed: false
        property SequentialAnimation positionResetAnim: SequentialAnimation {
            id: positionResetAnim
            property alias to: internalAnim.to
            NumberAnimation {
                id: internalAnim
                target: root
                to: drawerOpen ? 1 : 0
                property: "position"
                duration: (root.position)*Kirigami.Units.longDuration
            }
            ScriptAction {
                script: {
                    root.drawerOpen = internalAnim.to !== 0;
                }
            }
        }
        readonly property Item statesItem: Item {
            states: [
                State {
                    when: root.collapsed
                    PropertyChanges {
                        target: root
                        implicitWidth: edge === Qt.TopEdge || edge === Qt.BottomEdge ? applicationWindow().width : Math.min(collapsedSize + leftPadding + rightPadding, Math.round(applicationWindow().width*0.8))

                        implicitHeight: edge === Qt.LeftEdge || edge === Qt.RightEdge ? applicationWindow().height : Math.min(collapsedSize + topPadding + bottomPadding, Math.round(applicationWindow().height*0.8))
                    }
                },
                State {
                    when: !root.collapsed
                    PropertyChanges {
                        target: root
                        implicitWidth: edge === Qt.TopEdge || edge === Qt.BottomEdge ? applicationWindow().width : Math.min(contentItem.implicitWidth, Math.round(applicationWindow().width*0.8))

                        implicitHeight: edge === Qt.LeftEdge || edge === Qt.RightEdge ? applicationWindow().height : Math.min(contentHeight + topPadding + bottomPadding, Math.round(applicationWindow().height*0.4))

                        contentWidth: contentItem.implicitWidth || (contentChildren.length === 1 ? contentChildren[0].implicitWidth : 0)
                        contentHeight: contentItem.implicitHeight || (contentChildren.length === 1 ? contentChildren[0].implicitHeight : 0)
                    }
                }
            ]
            transitions: Transition {
                reversible: true
                NumberAnimation {
                    properties: root.edge === Qt.TopEdge || root.edge === Qt.BottomEdge ? "implicitHeight" : "implicitWidth"
                    duration: Kirigami.Units.longDuration
                    easing.type: Easing.InOutQuad
                }
            }
        }
    }
}