using System;
using System.Text;
using System.Text.RegularExpressions;
using CSNetwork;

namespace BrewMonster.Scripts.Chat
{
    /// <summary>
    /// Chat 输入/协议：wire（MarshalEditBoxText）↔ TMP &lt;sprite&gt; 显示。
    /// Chat input/protocol: wire (MarshalEditBoxText) ↔ TMP &lt;sprite&gt; display.
    /// </summary>
    public static class ChatWireTmpCodec
    {
        /// <summary>
        /// Thẻ &lt;sprite …&gt; nội bộ (TMP cho phép &lt;sprite=&quot;asset&quot; …&gt; không có khoảng sau &quot;sprite&quot;).
        /// English: Inner &lt;sprite …&gt; tag (TMP allows &lt;sprite=&quot;asset&quot; …&gt; with no space after &quot;sprite&quot;).
        /// </summary>
        private static readonly Regex InnerSpriteTagRegex = new Regex(@"<sprite[^>]*>", RegexOptions.IgnoreCase | RegexOptions.Compiled);

        /// <summary>
        /// Một emoji hiển thị trong input = &lt;size&gt; + sprite + &lt;/size&gt; (EmotionTMPTagBuilder).
        /// English: One in-game emoji in input = size wrapper + sprite + closing size tag.
        /// </summary>
        private static readonly Regex EmotionSizedBlockRegex =
            new Regex(@"<size=\d+%>\s*<sprite[^>]*>\s*</size>", RegexOptions.IgnoreCase | RegexOptions.Compiled);

        private static readonly Regex OrphanSpriteFragmentRegex = new Regex(@"^\s*sprite\s[^>]*>", RegexOptions.IgnoreCase | RegexOptions.Compiled);

        /// <summary>
        /// Tạo một đoạn wire marshal cho một emotion (set:index) — gửi server đúng protocol.
        /// Build one marshaled wire segment for a single emotion (set:index) — correct server protocol.
        /// </summary>
        public static string BuildMarshaledEmotionWire(int emotionSet, int emotionIndex)
        {
            var item = new EditBoxItemBase(AUICommon.EditboxItemType.enumEIEmotion);
            item.SetName("W");
            item.SetInfo(AUICommon.MarshalEmotionInfo(emotionSet, emotionIndex));
            var items = new EditBoxItemsSet();
            char c = items.AppendItem(item);
            if (c == '\0')
                return "";

            string display = c.ToString();
            return AUICommon.MarshalEditBoxText(display, items);
        }

        /// <summary>
        /// TMP 正文（无频道前缀）→ wire marshal（用于发送）。
        /// TMP body text (no channel prefix) → marshaled wire (for sending).
        /// </summary>
        public static string TmpBodyToWire(string tmpBody, IEmotionSpriteMap map)
        {
            if (string.IsNullOrEmpty(tmpBody))
                return "";
            if (map == null)
                return tmpBody;

            var sb = new StringBuilder(tmpBody.Length);
            int last = 0;
            foreach (Match block in EmotionSizedBlockRegex.Matches(tmpBody))
            {
                AppendTmpSegmentToWire(sb, tmpBody, last, block.Index - last, map);
                last = block.Index + block.Length;

                Match inner = InnerSpriteTagRegex.Match(block.Value);
                if (inner.Success && TryMatchSpriteTagToEmotion(map, inner.Value, out int es, out int ei))
                    sb.Append(BuildMarshaledEmotionWire(es, ei));
                else
                    sb.Append(block.Value);
            }

            AppendTmpSegmentToWire(sb, tmpBody, last, tmpBody.Length - last, map);
            return sb.ToString();
        }

        /// <summary>
        /// Đoạn TMP (không gồm khối &lt;size&gt;…&lt;/size&gt; đã xử lý ở ngoài): chữ thường + &lt;sprite&gt; rời.
        /// English: TMP segment: plain text plus bare sprite tags (outside size-wrapped emotion blocks).
        /// </summary>
        private static void AppendTmpSegmentToWire(StringBuilder sb, string tmpBody, int start, int length, IEmotionSpriteMap map)
        {
            if (length <= 0)
                return;

            string gap = tmpBody.Substring(start, length);
            int last = 0;
            foreach (Match m in InnerSpriteTagRegex.Matches(gap))
            {
                AppendSanitizedPlainText(sb, gap, last, m.Index - last);
                string tag = m.Value;
                if (TryMatchSpriteTagToEmotion(map, tag, out int es, out int ei))
                    sb.Append(BuildMarshaledEmotionWire(es, ei));
                else
                    sb.Append(tag);
                last = m.Index + m.Length;

                var orphan = OrphanSpriteFragmentRegex.Match(gap, last);
                if (orphan.Success)
                    last += orphan.Length;
            }

            AppendSanitizedPlainText(sb, gap, last, gap.Length - last);
        }

        private static void AppendSanitizedPlainText(StringBuilder sb, string source, int start, int length)
        {
            if (length <= 0)
                return;

            int end = start + length;
            for (int i = start; i < end; i++)
            {
                char ch = source[i];
                if (!AUICommon.IsEditboxItemCode(ch))
                    sb.Append(ch);
            }
        }

        /// <summary>
        /// Nếu charIndex nằm trong một emoji TMP (khối &lt;size&gt;… hoặc thẻ &lt;sprite&gt; rời), trả khoảng xóa [start, end).
        /// English: If charIndex is inside one TMP emoji unit, returns delete span [start, end).
        /// </summary>
        public static bool TryGetSpriteTagRangeContainingCharacterIndex(string text, int charIndex, out int tagStart, out int tagEndExclusive)
        {
            tagStart = 0;
            tagEndExclusive = 0;
            if (string.IsNullOrEmpty(text) || charIndex < 0 || charIndex >= text.Length)
                return false;

            foreach (Match m in EmotionSizedBlockRegex.Matches(text))
            {
                int end = m.Index + m.Length;
                if (charIndex >= m.Index && charIndex < end)
                {
                    tagStart = m.Index;
                    tagEndExclusive = end;
                    return true;
                }
            }

            foreach (Match m in InnerSpriteTagRegex.Matches(text))
            {
                int end = m.Index + m.Length;
                if (charIndex >= m.Index && charIndex < end)
                {
                    tagStart = m.Index;
                    tagEndExclusive = end;
                    return true;
                }
            }

            return false;
        }

        /// <summary>
        /// Khớp tag &lt;sprite…&gt; với EmotionTMPTagBuilder — so sánh phần sprite bên trong &lt;size&gt;…&lt;/size&gt;.
        /// English: Match inner &lt;sprite…&gt; to EmotionTMPTagBuilder output (full tag includes size wrapper).
        /// </summary>
        public static bool TryMatchSpriteTagToEmotion(IEmotionSpriteMap map, string spriteTag, out int emotionSet, out int emotionIndex)
        {
            emotionSet = 0;
            emotionIndex = 0;
            if (map == null || string.IsNullOrEmpty(spriteTag))
                return false;

            string normalized = spriteTag.Trim();
            for (int s = 0; s < AUICommon.AUIMANAGER_MAX_EMOTIONGROUPS; s++)
            {
                for (int e = 0; e < 512; e++)
                {
                    if (!EmotionTMPTagBuilder.TryBuildEmotionTag(map, s, e, out string built))
                        continue;

                    Match builtSprite = InnerSpriteTagRegex.Match(built);
                    if (!builtSprite.Success)
                        continue;
                    if (string.Equals(builtSprite.Value, normalized, StringComparison.OrdinalIgnoreCase))
                    {
                        emotionSet = s;
                        emotionIndex = e;
                        return true;
                    }
                }
            }

            return false;
        }

        /// <summary>
        /// Wire → TMP 富文本（FilterEmotionSet + Unmarshal + ConvertInlineItemsToTmp）。
        /// Wire → TMP rich text (FilterEmotionSet + Unmarshal + ConvertInlineItemsToTmp).
        /// </summary>
        public static string WireBodyToTmpForDisplay(string wireBody, IEmotionSpriteMap map, int cEmotion)
        {
            return ChatEmotionDisplayPipeline.ConvertWireBodyToTmpDisplay(wireBody, map, cEmotion);
        }
    }
}