// SPDX-License-Identifier: Unlicense

import QtQuick 2.14
import QtQuick.Controls 2.13
import QtQuick.Layouts 1.6
import QtMultimedia 5.11

Page {
    property bool loaded:
        media.status !== MediaPlayer.NoMedia &&
        media.status !== MediaPlayer.InvalidMedia &&
        media.status !== MediaPlayer.UnknownStatus
    property alias source: media.source
    property alias time: media.position

    function pause(yes) {
        if (yes === undefined)
            yes = media.playbackState === MediaPlayer.PlayingState
        if (yes)
            media.pause()
        else
            media.play()
    }

    function seek(offset, relative) {
        if (relative)
            offset += media.position
        media.seek(offset)
    }

    Keys.onPressed: {
        switch (event.key) {
        // (Un)pause video.
        case Qt.Key_Space:
            pause()
            break
        // Seek video.
        case Qt.Key_Left:
            seek(-500, true)
            break
        case Qt.Key_Right:
            seek(500, true)
            break
        // Change playback rate.
        case Qt.Key_Equal:
            rate.reset()
            break
        case Qt.Key_Comma:
            rate.decrease()
            break
        case Qt.Key_Period:
            rate.increase()
            break
        default:
            return // don’t accept the event
        }
        event.accepted = true
    }

    // Video.
    ColumnLayout {
        spacing: 0
        anchors.fill: parent

        Rectangle {
            Layout.fillWidth: true
            Layout.fillHeight: true
            color: 'black'
            clip: true

            VideoOutput {
                anchors.fill: parent
                fillMode: VideoOutput.PreserveAspectFit
                source: media

                transform: Scale {
                    id: zoom
                    property real scale: 1.0
                    xScale: scale
                    yScale: scale
                    origin.x: wheel.point.position.x
                    origin.y: wheel.point.position.y
                }

                MediaPlayer {
                    id: media
                    notifyInterval: 100
                    playbackRate: Number.fromLocaleString(rate.displayText)
                    volume: QtMultimedia.convertVolume(
                        volume.value,
                        QtMultimedia.LogarithmicVolumeScale,
                        QtMultimedia.LinearVolumeScale)
                }

                TapHandler {
                    acceptedButtons: Qt.RightButton
                    onTapped: pause()
                }

                WheelHandler {
                    id: wheel
                    onWheel: zoom.scale = Math.max(1.0, (event.angleDelta.y > 0 ? 1.1 : 0.9) * zoom.scale)
                }
            }
        }

        // Video controls.
        RowLayout {
            Layout.margins: 5

            Button {
                icon.name: 'media-playback-pause'
                implicitWidth: implicitHeight
                checkable: true
                checked: media.playbackState !== MediaPlayer.PlayingState
                onClicked: checked ? media.pause() : media.play()
                focusPolicy: Qt.NoFocus
            }
            Label { text: new Date(media.position).toISOString().substr(12, 9) }
            Slider {
                Layout.fillWidth: true
                from: 0; to: media.duration
                value: media.position
                onMoved: media.seek(value)
                focusPolicy: Qt.NoFocus
            }
            Label { text: new Date(media.duration).toISOString().substr(12, 7) }

            Volume {
                id: volume
                muted: media.muted
                focusPolicy: Qt.NoFocus
            }

            // Playback speed control.
            SpinBox {
                id: rate
                implicitWidth: 80

                from: 25; to: 250; stepSize: 25
                value: 100

                function reset() { value = 100 }

                textFromValue: function (value, locale) {
                    return (value / 100).toLocaleString(locale, 'f', 2)
                }
            }
        }
    }
}