// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-1.1 OR LicenseRef-Slint-commercial

import { CosmicPalette } from "styling.slint";
import { StateLayerBase } from "components.slint";

export component Slider {
    in property <Orientation> orientation: horizontal;
    in property <float> maximum: 100;
    in property <float> minimum: 0;
    in property <bool> enabled <=> touch-area.enabled;
    out property <bool> has-focus: focus-scope.has-focus;
    in-out property <float> value;

    callback changed( /* value */ float);

    private property <bool> vertical: orientation == Orientation.vertical;

    min-width: vertical ? 20px : 0px;
    min-height: vertical ? 0px : 20px;
    vertical-stretch: vertical ? 1 : 0;
    horizontal-stretch: vertical ? 0 : 1;
    accessible-role: slider;
    accessible-value: root.value;
    accessible-value-minimum: root.minimum;
    accessible-value-maximum: root.maximum;
    accessible-value-step: (root.maximum - root.minimum) / 100;

    states [
        disabled when !root.enabled : {
            opacity: 0.5;
        }
    ]

    rail := Rectangle {
        width: vertical ? 4px : parent.width;
        height: vertical ? parent.height : 4px;
        background: CosmicPalette.neutral-6-background;
        border-radius: 2px;
    }

    track := Rectangle {
        x: vertical ? (parent.width - self.width) / 2 : 0;
        y: vertical ? 0 : (parent.height - self.height) / 2;
        width: vertical ? rail.width : thumb.x + (thumb.width / 2);
        height: vertical ? thumb.y + (thumb.height / 2) : rail.height;
        background: CosmicPalette.secondary-accent-background;
        border-radius: rail.border-radius;
    }

    thumb := Rectangle {
        x: vertical ? (parent.width - self.width) / 2 : (parent.width - self.width) * (root.value - root.minimum) / (root.maximum - root.minimum);
        y: vertical ? (parent.height - self.height) * (root.value - root.minimum) / (root.maximum - root.minimum) : (parent.height - self.height) / 2;
        width: 20px;
        height: self.width;
        border-radius: 10px;
        background: CosmicPalette.accent-background;

        StateLayerBase {
            width: parent.width + 8px;
            height: parent.height + 8px;
            border-radius: max(self.width, self.height) / 2;
            enabled: touch-area.enabled;
            focus-boder-margin: 0px;
            pressed: touch-area.pressed;
            has-hover: touch-area.has-hover;
            has-focus: focus-scope.has-focus;
        }
    }

    touch-area := TouchArea {
        property <float> pressed-value;

        width: parent.width;
        height: parent.height;

        pointer-event(event) => {
            if (event.button == PointerEventButton.left && event.kind == PointerEventKind.down) {
                self.pressed-value = root.value;
            }
        }

        moved => {
            if (!vertical && self.enabled && self.pressed) {
                root.value = max(root.minimum, min(root.maximum,
                    self.pressed-value + (touch-area.mouse-x - touch-area.pressed-x) * (root.maximum - root.minimum) / (root.width - thumb.width)));
                root.changed(root.value);
            }
            if (vertical && self.enabled && self.pressed) {
                root.value = max(root.minimum, min(root.maximum,
                    self.pressed-value + (touch-area.mouse-y - touch-area.pressed-y) * (root.maximum - root.minimum) / (root.height - thumb.height)));
                root.changed(root.value);
            }
        }
    }

    focus-scope := FocusScope {
        x: 0;
        y: 0;
        width: 0;
        height: 0;

        key-pressed(event) => {
            if (!vertical && self.enabled && event.text == Key.RightArrow) {
                root.value = Math.min(root.value + 1, root.maximum);
                accept
            } else if (!vertical && self.enabled && event.text == Key.LeftArrow) {
                root.value = Math.max(root.value - 1, root.minimum);
                accept
            } else if (vertical && self.enabled && event.text == Key.DownArrow) {
                root.value = Math.min(root.value + 1, root.maximum);
                accept
            } else if (vertical && self.enabled && event.text == Key.UpArrow) {
                root.value = Math.max(root.value - 1, root.minimum);
                accept
            } else {
                reject
            }
        }
    }
}