namespace DodoSSH.Client.Shell.Keyboard;

/// <summary>What pressing a terminal key does.</summary>
internal enum TerminalKeyKind
{
    /// <summary>Sends its bytes, after any latched modifier has had its say.</summary>
    Send,

    /// <summary>Latches Ctrl for the next key, and releases itself after it.</summary>
    Control,

    /// <summary>Latches Alt for the next key, and releases itself after it.</summary>
    Alt,

    /// <summary>Pastes the clipboard, through the same path a right-click on the desktop takes.</summary>
    Paste,
}

/// <summary>
/// One key the phone's own keyboard does not have.
/// </summary>
/// <remarks>
/// <para>
/// A record for the convenience of construction and nothing else: two keys are the same key when their
/// <see cref="Id"/> is, which is what the bar stores. The byte array would make record equality reference
/// equality anyway, so nothing here leans on it.
/// </para>
/// <para>
/// <see cref="IsWide"/> exists for the labels that are words — <c>ctrl+B %</c> — which want two cells on
/// the quick-access keyboard where an arrow wants one. It is a fact about the label rather than a layout
/// choice made per screen, so it lives here.
/// </para>
/// </remarks>
/// <param name="Id">Stable across releases; the bar and the group order are stored by it.</param>
/// <param name="Label">What the key says.</param>
/// <param name="Kind">What pressing it does.</param>
/// <param name="Bytes">What it sends, for <see cref="TerminalKeyKind.Send"/>. Empty otherwise.</param>
/// <param name="Hint">What it is for, for the customise screen and for accessibility.</param>
internal sealed record TerminalKey(string Id, string Label, TerminalKeyKind Kind, byte[] Bytes, string Hint)
{
    /// <summary>Whether the label is long enough to want a double-width cell.</summary>
    internal bool IsWide => Label.Length > 4;

    /// <summary>Whether this is one of the two latching modifiers.</summary>
    internal bool IsModifier => Kind is TerminalKeyKind.Control or TerminalKeyKind.Alt;

    /// <summary>Whether this key was added by the person using it rather than shipped.</summary>
    internal bool IsCustom => Id.StartsWith(TerminalKeyCatalog.CustomPrefix, StringComparison.Ordinal);
}

/// <summary>A named set of keys on the quick-access keyboard.</summary>
/// <param name="Id">Stable across releases; the order and the hidden set are stored by it.</param>
/// <param name="Title">The caption above the keys.</param>
/// <param name="Keys">The keys, in the order they are drawn.</param>
internal sealed record TerminalKeyGroup(string Id, string Title, IReadOnlyList<TerminalKey> Keys);