namespace AcDream.App.UI.Layout;

/// <summary>
/// Campaign FA slice FA3: shared row-text lookup for the social panel's
/// Friends/Squelch read-only list rows. Both row templates
/// (<c>0x2100005D</c>/<c>0x10000519</c> for Friends,
/// <c>0x21000060</c>/<c>0x10000541</c> for Squelch — FA3 live-mount probe)
/// author the SAME two-deep nested-text shape: a Type-3 row root, one
/// Type-0xC text child, and ONE MORE Type-0xC text grandchild at the
/// identical rect. Neither <c>gmFriendsUI</c> nor <c>gmSquelchUI</c> is in
/// this campaign's decompiled scope (lane A/B/C/D cover only Fellowship/
/// Allegiance), so which of the two carries the actual glyph flow is not
/// established from retail decomp — the innermost leaf is used here
/// (deepest-first is the common "structural wrapper, then label leaf"
/// shape elsewhere in this dat format).
/// </summary>
internal static class SocialPanelRowText
{
    /// <summary>
    /// Returns the LAST <see cref="UiText"/> found by a pre-order walk of
    /// <paramref name="row"/> (row itself, then each child's own subtree in
    /// order), or null if the built row contains no text element at all.
    /// <b>Fix-round mechanism SF-9:</b> this equals the truly DEEPEST match
    /// only when the subtree is a single chain — both real row templates
    /// (Friends <c>0x10000519</c>, Squelch <c>0x10000541</c>) ARE single
    /// chains (row root -&gt; one Type-0xC text child -&gt; one more Type-0xC
    /// text grandchild, per the FA3 live-mount probe), so this method's
    /// actual "last match in traversal order" behavior and the class doc's
    /// "deepest" framing agree for both templates in production today. A
    /// row template with a BRANCHING subtree (multiple text leaves at
    /// different depths) would expose the difference.
    /// </summary>
    public static UiText? FindDeepest(UiElement row)
    {
        UiText? found = row as UiText;
        foreach (UiElement child in row.Children)
        {
            if (FindDeepest(child) is { } deeper)
                found = deeper;
        }
        return found;
    }
}