// SPDX-FileCopyrightText: 2023 Devin Lin <devin@kde.org>
// SPDX-License-Identifier: GPL-2.0-or-later

pragma Singleton

import QtQuick

import org.kde.plasma.private.volume

QtObject {
    id: root

    property var config: GlobalConfig {}

    property SinkModel paSinkModel: SinkModel {}

    // whether the audio icon should be visible in the status bar
    readonly property bool isVisible: PreferredDevice.sink

    // the icon that should be displayed in the status bar
    readonly property string icon: PreferredDevice.sink && !isDummyOutput(PreferredDevice.sink)
                                    ? iconName(PreferredDevice.sink.volume, PreferredDevice.sink.muted)
                                    : iconName(0, true)

    // the name of the audio device when it isn't valid
    readonly property string dummyOutputName: "auto_null"

    // the maximum volume amount (percentage)
    readonly property int maxVolumePercent: config.raiseMaximumVolume ? 150 : 100

    // the maximum volume amount
    readonly property int maxVolumeValue: maxVolumePercent * PulseAudio.NormalVolume / 100

    // step that increments when adjusting the volume
    readonly property int volumeStep: Math.round(5 * PulseAudio.NormalVolume / 100.0)

    // The current audio volume (updated by connecting to sinks)
    property int volumeValue

    function isDummyOutput(output) {
        return output && output.name === dummyOutputName;
    }

    function boundVolume(volume) {
        return Math.max(PulseAudio.MinimalVolume, Math.min(volume, maxVolumeValue));
    }

    function volumePercent(volume, max){
        if (!max) {
            max = PulseAudio.NormalVolume;
        }
        return Math.round(volume / max * maxVolumePercent);
    }

    function increaseVolume() {
        if (!PreferredDevice.sink || isDummyOutput(PreferredDevice.sink)) {
            return;
        }

        var volume = boundVolume(PreferredDevice.sink.volume + volumeStep);
        var percent = volumePercent(volume, maxVolumeValue);
        PreferredDevice.sink.muted = percent == 0;
        PreferredDevice.sink.volume = volume;
    }

    function decreaseVolume() {
        if (!PreferredDevice.sink || isDummyOutput(PreferredDevice.sink)) {
            return;
        }

        var volume = boundVolume(PreferredDevice.sink.volume - volumeStep);
        var percent = volumePercent(volume, maxVolumeValue);
        PreferredDevice.sink.muted = percent == 0;
        PreferredDevice.sink.volume = volume;
    }

    function muteVolume() {
        if (!PreferredDevice.sink || isDummyOutput(PreferredDevice.sink)) {
            return;
        }

        PreferredDevice.sink.muted = !PreferredDevice.sink.muted;
    }

    function iconName(volume, muted, prefix) {
        if (!prefix) {
            prefix = "audio-volume";
        }
        var icon = null;
        var percent = volume / maxVolumeValue;
        if (percent <= 0.0 || muted) {
            icon = prefix + "-muted";
        } else if (percent <= 0.25) {
            icon = prefix + "-low";
        } else if (percent <= 0.75) {
            icon = prefix + "-medium";
        } else {
            icon = prefix + "-high";
        }
        return icon;
    }

    // emitted when the volume changed, but not due to sink switching
    signal volumeChanged()

    property var updateVolume: Connections {
        target: root.paSinkModel ? (PreferredDevice.sink ? PreferredDevice.sink : null) : null
        enabled: target !== null

        function onVolumeChanged() {
            root.volumeValue = root.volumePercent(PreferredDevice.sink.volume, root.maxVolumeValue);
            root.volumeChanged();
        }

        function onMutedChanged() {
            root.volumeValue = PreferredDevice.sink.muted ? 0 : root.volumePercent(PreferredDevice.sink.volume, root.maxVolumeValue);
            root.volumeChanged();
        }
    }

    property var updateVolumeOnSinkChange: Connections {
        target: root.paSinkModel ? root.paSinkModel : null
        enabled: target !== null

        function onPreferredSinkChanged() {
            if (PreferredDevice.sink) {
                root.volumeValue = root.volumePercent(PreferredDevice.sink.volume, root.maxVolumeValue);
            }
        }
    }
}