using UnityEngine;
using UnityEngine.UIElements;

namespace ProjectM.Client
{
    /// <summary>
    /// UI Toolkit factories for the in-game HUD — a thin extension of <see cref="MenuUi"/>'s Aether palette,
    /// now skinned with the curated Synty sci-fi-soldier kit (<see cref="HudTheme"/>). Panels are 9-sliced Synty
    /// boxes tinted into the Aether palette; bars are a skinned track + a percent-width fill; numerics use the
    /// Orbitron display font and labels the Exo 2.0 body font. EVERYTHING is null-safe: if <see cref="HudTheme"/>
    /// (or a given sprite/font) is missing, each factory falls back to the original flat-colour look, so the HUD
    /// is shippable with or without the theme asset. Every element is <c>pickingMode = Ignore</c> by default so
    /// the HUD never eats clicks meant for the game world (only the interactive build-palette slots opt back in).
    /// </summary>
    public static class HudUi
    {
        public static readonly Color Track = new(0f, 0f, 0f, 0.55f);

        // ---- text (Orbitron display vs Exo body, theme-driven with a bold fallback) ----

        /// <summary>A body label (Exo 2.0 when themed) — labels, captions, hints.</summary>
        public static Label Text(string text, int size, Color color, TextAnchor align)
        {
            var l = MakeLabel(text, size, color, align);
            var theme = HudTheme.Get();
            if (theme != null) theme.ApplyBody(l.style);
            return l;
        }

        /// <summary>A display label (Orbitron when themed) — numerics + phase words, the authoritative HUD voice.</summary>
        public static Label Display(string text, int size, Color color, TextAnchor align)
        {
            var l = MakeLabel(text, size, color, align);
            var theme = HudTheme.Get();
            if (theme != null) theme.ApplyDisplay(l.style);
            return l;
        }

        static Label MakeLabel(string text, int size, Color color, TextAnchor align)
        {
            var l = new Label(text);
            l.style.fontSize = size;
            l.style.color = color;
            l.style.unityTextAlign = align;
            l.style.unityFontStyleAndWeight = FontStyle.Bold;
            l.pickingMode = PickingMode.Ignore;
            return l;
        }

        // ---- bars ----

        /// <summary>A dark rounded bar track with a percent-width fill child (returned via <paramref name="fill"/>).</summary>
        public static VisualElement Bar(float width, float height, Color fillColor, out VisualElement fill)
        {
            var theme = HudTheme.Get();
            var trackSpr = theme != null ? theme.BarTrack : null;

            var track = new VisualElement();
            track.style.width = width;
            track.style.height = height;
            track.style.paddingLeft = 2; track.style.paddingRight = 2;
            track.style.paddingTop = 2; track.style.paddingBottom = 2;
            track.style.flexDirection = FlexDirection.Row;
            track.pickingMode = PickingMode.Ignore;

            fill = new VisualElement();
            fill.style.height = Length.Percent(100);
            fill.style.width = Length.Percent(100);
            fill.style.backgroundColor = fillColor;
            fill.pickingMode = PickingMode.Ignore;
            MenuUi.Round(fill, 3);

            if (trackSpr != null)
            {
                // Bar_Angled ships an 80/0 border → UITK 9-slices it horizontally from the art; no style override.
                track.style.backgroundImage = new StyleBackground(Background.FromSprite(trackSpr));
                track.style.unityBackgroundImageTintColor = new Color(0.04f, 0.06f, 0.09f, 0.92f);
            }
            else
            {
                track.style.backgroundColor = Track;
                MenuUi.Round(track, 4);
            }

            track.Add(fill);
            return track;
        }

        /// <summary>Set a fill's width to a 0..1 fraction of its track.</summary>
        public static void SetFill(VisualElement fill, float frac)
        {
            if (fill != null) fill.style.width = Length.Percent(Mathf.Clamp01(frac) * 100f);
        }

        // ---- panels / icons / glyphs ----

        /// <summary>A grouping container (no background). Transparent, click-through.</summary>
        public static VisualElement Group(Align items = Align.FlexStart)
        {
            var g = new VisualElement();
            g.style.alignItems = items;
            g.pickingMode = PickingMode.Ignore;
            return g;
        }

        /// <summary>
        /// A 9-sliced Synty panel tinted into the Aether palette; falls back to a flat translucent rounded panel
        /// when the theme/sprite is missing. <paramref name="tint"/> multiplies the (light-grey) skin, so a dark
        /// tint reads as panel-dark while preserving the printed bevels.
        /// </summary>
        public static VisualElement Panel(Color tint)
        {
            var p = new VisualElement();
            p.pickingMode = PickingMode.Ignore;
            var theme = HudTheme.Get();
            var box = theme != null ? theme.PanelBox : null;
            if (box != null)
            {
                p.style.backgroundImage = new StyleBackground(Background.FromSprite(box));
                p.style.unityBackgroundImageTintColor = tint;
                // 9-slice uses the sprite's AUTHORED border (Box_Glass ships 25px); no style override → no
                // "borders overridden by style slices" log, and the art's intended corners are preserved.
            }
            else
            {
                p.style.backgroundColor = tint;
                MenuUi.Round(p, 8);
                MenuUi.Border(p, new Color(1f, 1f, 1f, 0.08f), 1);
            }
            return p;
        }

        /// <summary>A fixed-size icon element backed by a Synty sprite (tinted). Returns an empty element if null.</summary>
        public static VisualElement Icon(Sprite sprite, float size, Color tint)
        {
            var e = new VisualElement();
            e.style.width = size; e.style.height = size;
            e.style.flexShrink = 0;
            e.pickingMode = PickingMode.Ignore;
            if (sprite != null)
            {
                e.style.backgroundImage = new StyleBackground(Background.FromSprite(sprite));
                e.style.unityBackgroundImageTintColor = tint;
                e.style.backgroundSize = new StyleBackgroundSize(new BackgroundSize(BackgroundSizeType.Contain));
            }
            return e;
        }

        /// <summary>True when the theme is loaded and a sprite is present (callers choose icon vs text fallback).</summary>


        /// <summary>
        /// An input-prompt chip: the Synty key/button glyph (left untinted to keep its printed face) when present,
        /// else a bordered text keycap with <paramref name="fallbackText"/> (e.g. "R", "Esc").
        /// </summary>
        public static VisualElement Glyph(Sprite sprite, string fallbackText, float size)
        {
            if (sprite != null) return Icon(sprite, size, Color.white);

            var cap = new VisualElement();
            cap.style.minWidth = size; cap.style.height = size;
            cap.style.paddingLeft = 7; cap.style.paddingRight = 7;
            cap.style.alignItems = Align.Center; cap.style.justifyContent = Justify.Center;
            cap.style.backgroundColor = new Color(0.14f, 0.17f, 0.22f, 0.95f);
            cap.style.flexShrink = 0;
            cap.pickingMode = PickingMode.Ignore;
            MenuUi.Round(cap, 4);
            MenuUi.Border(cap, new Color(1f, 1f, 1f, 0.25f), 1);
            cap.Add(Text(fallbackText, Mathf.Max(10, (int)(size * 0.5f)), MenuUi.TextCol, TextAnchor.MiddleCenter));
            return cap;
        }

        /// <summary>Apply a uniform 9-slice (horizontal / vertical source-texture px) to a skinned element.</summary>

    }
}