import { AppTheme } from "../design-system.slint";
import { TypeScale } from "../typography.slint";

// A `keys` value taken apart, so caps can follow each platform's order and
// names. Slint reports Command as `control` and Control as `meta` on Apple
// platforms, matching what `@keys(Control + …)` binds there.
export struct KeyChord {
    control: bool,
    alt: bool,
    shift: bool,
    meta: bool,
    key: string,
}

export global KeyboardKeys {
    // Slint cannot take a `keys` value apart, so Rust does.
    pure callback chord(keys) -> KeyChord;
    out property <bool> apple: Platform.os == OperatingSystemType.macos || Platform.os == OperatingSystemType.ios;
    out property <bool> windows: Platform.os == OperatingSystemType.windows;

    // The name printed on a key or modifier; Apple keyboards print symbols.
    public pure function label(key: string) -> string {
        if key == "Control" { return apple ? "⌘" : @tr("Keyboard key" => "Ctrl"); }
        if key == "Meta" { return apple ? "⌃" : windows ? "Win" : @tr("Keyboard key" => "Super"); }
        if key == "Alt" { return apple ? "⌥" : @tr("Keyboard key" => "Alt"); }
        if key == "Shift" { return apple ? "⇧" : @tr("Keyboard key" => "Shift"); }
        if key == Key.Delete { return apple ? "⌦" : @tr("Keyboard key" => "Delete"); }
        if key == Key.Backspace { return apple ? "⌫" : @tr("Keyboard key" => "Backspace"); }
        if key == Key.Tab { return apple ? "⇥" : @tr("Keyboard key" => "Tab"); }
        if key == Key.Return { return apple ? "↩" : @tr("Keyboard key" => "Enter"); }
        if key == Key.Space { return @tr("Keyboard key" => "Space"); }
        if key == Key.UpArrow { return "↑"; }
        if key == Key.DownArrow { return "↓"; }
        if key == Key.LeftArrow { return "←"; }
        if key == Key.RightArrow { return "→"; }
        if key == Key.F5 { return "F5"; }
        if key == Key.F6 { return "F6"; }
        if key == Key.F7 { return "F7"; }
        if key == "-" { return "−"; }
        return key.to-uppercase();
    }

    // The binding as one line, as screen readers and tooltips need it.
    public pure function text(keys: keys) -> string {
        let chord = chord(keys);
        let joiner = apple ? "" : "+";
        return (chord.meta ? label("Meta") + joiner : "")
            + (!apple && chord.control ? label("Control") + joiner : "")
            + (chord.alt ? label("Alt") + joiner : "")
            + (chord.shift ? label("Shift") + joiner : "")
            + (apple && chord.control ? label("Control") : "")
            + label(chord.key);
    }
}

// One key cap, after shadcn/ui's Kbd.
export component Kbd inherits Rectangle {
    in property <string> text;

    width: max(self.height, label.preferred-width + 10px);
    height: max(20px, label.preferred-height + 4px);
    border-radius: 4px;
    background: AppTheme.control-bg;
    border-width: 1px;
    border-color: AppTheme.border-subtle;
    accessible-role: none;

    label := Text {
        text: root.text;
        color: AppTheme.secondary;
        font-size: TypeScale.caption;
        font-weight: 500;
        horizontal-alignment: center;
        vertical-alignment: center;
        accessible-role: none;
    }
}

// Keys pressed together, after shadcn/ui's KbdGroup.
export component KbdGroup inherits HorizontalLayout {
    spacing: 4px;
    alignment: start;
    cross-axis-alignment: center;
    @children
}

// The caps for a key binding, in the platform's modifier order. Apple
// platforms put Command last: ⌃⌥⇧⌘.
export component KbdShortcut inherits KbdGroup {
    in property <keys> keys;
    private property <KeyChord> chord: KeyboardKeys.chord(root.keys);

    if root.chord.meta : Kbd { text: KeyboardKeys.label("Meta"); }
    if !KeyboardKeys.apple && root.chord.control : Kbd { text: KeyboardKeys.label("Control"); }
    if root.chord.alt : Kbd { text: KeyboardKeys.label("Alt"); }
    if root.chord.shift : Kbd { text: KeyboardKeys.label("Shift"); }
    if KeyboardKeys.apple && root.chord.control : Kbd { text: KeyboardKeys.label("Control"); }
    Kbd { text: KeyboardKeys.label(root.chord.key); }
}