using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.Json;

namespace AnotherReplayReader.Utils
{
    /// <summary>
    /// Predefined tag taxonomy for KnowledgeEntry.
    /// Tags bridge prompt rendering and validation logic.
    /// </summary>
    internal static class KnowledgeTag
    {
        // ── Capability tags (what a unit can do) ──────────────────────
        public const string Builder = "builder";
        public const string Pack = "pack";
        public const string Unpack = "unpack";
        public const string Amphibious = "amphibious";
        public const string Transport = "transport";
        public const string ReturnToProducer = "returnToProducer";
        public const string Cloak = "cloak";
        public const string ToggleWeapon = "toggleWeapon";

        // ── Type tags (what a unit is) ────────────────────────────────
        public const string Infantry = "infantry";
        public const string Vehicle = "vehicle";
        public const string Aircraft = "aircraft";
        public const string Naval = "naval";
        public const string Structure = "structure";
        public const string Hero = "hero";
        public const string Production = "production";
        public const string Defense = "defense";
        public const string Superweapon = "superweapon";
        public const string Land = "land";
        public const string Sea = "sea";
        public const string Air = "air";

        // ── Combat role tags (what a unit fights) ─────────────────────
        public const string AntiInfantry = "antiInfantry";
        public const string AntiVehicle = "antiVehicle";
        public const string AntiStructure = "antiStructure";
        public const string AntiAir = "antiAir";
        public const string AntiNaval = "antiNaval";
        public const string AntiGround = "antiGround";

        // ── 其余 JSON 实际使用的角色/定位标签 ──────────────────────────
        public const string Miner = "miner";
        public const string Scout = "scout";
        public const string Support = "support";
        public const string Siege = "siege";
        public const string Bomber = "bomber";
        public const string Engineer = "engineer";
        public const string Fighter = "fighter";

        /// <summary>完整标签集合：加载 JSON 时校验未知 tag 用。</summary>
        public static readonly ImmutableArray<string> All = ImmutableArray.Create(
            Builder, Pack, Unpack, Amphibious, Transport, ReturnToProducer, Cloak, ToggleWeapon,
            Miner, Scout, Support, Siege, Bomber,
            Infantry, Vehicle, Aircraft, Naval, Structure, Hero, Production, Defense, Superweapon,
            Land, Sea, Air,
            AntiInfantry, AntiVehicle, AntiStructure, AntiAir, AntiNaval, AntiGround,
            Engineer, Fighter);

        /// <summary>Create a special power reference tag.</summary>
        public static string SpecialPower(string powerName) => $"specialPower:{powerName}";
    }

    /// <summary>
    /// The scope kind of a knowledge entry within a KnowledgeSet.
    /// Scope is determined by the entry's position in the hierarchy,
    /// not stored in the entry itself.
    /// </summary>
    internal enum KnowledgeScopeKind
    {
        Global,
        Faction,
        Map
    }

    /// <summary>
    /// Identifies which scope a knowledge entry belongs to.
    /// </summary>
    internal sealed record KnowledgeScope(KnowledgeScopeKind Kind, string? Name = null)
    {
        public static KnowledgeScope Global { get; } = new(KnowledgeScopeKind.Global);
        public static KnowledgeScope Faction(string name) => new(KnowledgeScopeKind.Faction, name);
        public static KnowledgeScope Map(string id) => new(KnowledgeScopeKind.Map, id);
    }

    /// <summary>
    /// The smallest reusable unit of game knowledge.
    /// Id is unique within a knowledge set; tags enable validation queries;
    /// text is the markdown description used for prompt rendering.
    /// </summary>
    internal sealed record KnowledgeEntry(
        string Id,
        ImmutableArray<string> Tags,
        string Text)
    {
        public bool HasTag(string tag) => Tags.Contains(tag, StringComparer.OrdinalIgnoreCase);
        public bool HasAnyTag(params string[] tags) => tags.Any(HasTag);
    }

    // ── Structured game entity knowledge ───────────────────────────────

    /// <summary>A special power with its observable name and description.</summary>
    internal sealed record SpecialPowerInfo(string Name, string Description);

    /// <summary>
    /// Structured knowledge about a game entity (unit or building).
    /// Buildings omit <see cref="Tier"/> and <see cref="ProducedBy"/>;
    /// the <c>structure</c> tag distinguishes them from units.
    /// </summary>
    internal sealed record EntityKnowledge(
        string AssetName,
        string DisplayName,
        string Faction,
        string? Tier,
        ImmutableArray<string> Tags,
        ImmutableArray<SpecialPowerInfo> SpecialPowers,
        ImmutableArray<string> ProducedBy,
        ImmutableArray<string> Aliases,
        string Text)
    {
        public bool IsBuilding => HasTag(KnowledgeTag.Structure);
        public bool IsUnit => !IsBuilding;
        public bool HasTag(string tag) => Tags.Contains(tag, StringComparer.OrdinalIgnoreCase);
        public bool HasSpecialPower(string name) =>
            SpecialPowers.Any(sp => string.Equals(sp.Name, name, StringComparison.OrdinalIgnoreCase));
    }

    /// <summary>
    /// In-memory index of structured game knowledge loaded from knowledge_units.json.
    /// Used by validation to query unit capabilities deterministically.
    /// </summary>
    internal sealed class StructuredKnowledge
    {
        public ImmutableDictionary<string, EntityKnowledge> EntitiesByAssetName { get; }
        public ImmutableArray<EntityKnowledge> AllEntities { get; }
        public ImmutableDictionary<string, ImmutableArray<EntityKnowledge>> EntitiesByFaction { get; }
        public ImmutableArray<string> UnknownTags { get; }

        private StructuredKnowledge(
            ImmutableDictionary<string, EntityKnowledge> byAsset,
            ImmutableArray<EntityKnowledge> allEntities,
            ImmutableDictionary<string, ImmutableArray<EntityKnowledge>> byFaction,
            ImmutableArray<string> unknownTags)
        {
            EntitiesByAssetName = byAsset;
            AllEntities = allEntities;
            EntitiesByFaction = byFaction;
            UnknownTags = unknownTags;
        }

        // ── Query helpers ────────────────────────────────────────────

        public ImmutableArray<EntityKnowledge> EntitiesWithTag(string tag) =>
            AllEntities.Where(e => e.HasTag(tag)).ToImmutableArray();

        public ImmutableArray<EntityKnowledge> EntitiesWithSpecialPower(string power) =>
            AllEntities.Where(e => e.HasSpecialPower(power)).ToImmutableArray();

        public EntityKnowledge? GetEntity(string? assetName) =>
            assetName is not null && EntitiesByAssetName.TryGetValue(assetName, out var e) ? e : null;

        public bool IsKnownBuilder(string? assetName) =>
            GetEntity(assetName)?.HasTag(KnowledgeTag.Builder) == true;

        public bool EntityHasSpecialPower(string? assetName, string? powerName) =>
            assetName is not null && powerName is not null &&
            GetEntity(assetName)?.HasSpecialPower(powerName) == true;

        // ── Factory ──────────────────────────────────────────────────

        private static readonly Lazy<StructuredKnowledge?> _lazyDefault = new(() => GetForMod("default"));

        public static StructuredKnowledge? Instance => _lazyDefault.Value;

        private static readonly ConcurrentDictionary<string, StructuredKnowledge?> _cache =
            new(StringComparer.OrdinalIgnoreCase);

        /// <summary>按 mod 加载结构化知识；文件不存在返回 null（该 mod 无结构化数据）。</summary>
        public static StructuredKnowledge? GetForMod(string? modName)
        {
            var key = modName ?? "default";
            if (_cache.TryGetValue(key, out var cached))
            {
                return cached;
            }
            var loaded = LoadFromFile(key);
            if (loaded is not null)
            {
                _cache.TryAdd(key, loaded);
            }
            return loaded;
        }

        /// <summary>Look up the display name for an asset name.</summary>
        public string? GetDisplayName(string? assetName) =>
            GetEntity(assetName)?.DisplayName;

        private static StructuredKnowledge? LoadFromFile(string modName)
        {
            var path = Path.Combine(AppContext.BaseDirectory, $"knowledge_units_{modName}.json");
            if (!File.Exists(path)) return null;

            try
            {
                var builtin = ParseFactions(path, out var unknownTags);
                if (builtin is null)
                {
                    return null;
                }

                // 用户知识覆盖：AnotherReplayReader.user_knowledge.json，按 (阵营, assetName) 覆盖或新增
                var userPath = Path.Combine(AppContext.BaseDirectory, "AnotherReplayReader.user_knowledge.json");
                if (File.Exists(userPath))
                {
                    var user = ParseFactions(userPath, out var userUnknownTags);
                    if (user is not null)
                    {
                        foreach (var kv in user)
                        {
                            if (!builtin.TryGetValue(kv.Key, out var factionEntries))
                            {
                                factionEntries = new Dictionary<string, EntityKnowledge>(StringComparer.OrdinalIgnoreCase);
                                builtin[kv.Key] = factionEntries;
                            }
                            foreach (var entity in kv.Value)
                            {
                                factionEntries[entity.Key] = entity.Value;
                            }
                            unknownTags.UnionWith(userUnknownTags);
                        }
                    }
                }

                var allEntities = builtin.Values
                    .SelectMany(d => d.Values)
                    .OrderBy(e => e.Faction, StringComparer.OrdinalIgnoreCase)
                    .ThenBy(e => e.AssetName, StringComparer.OrdinalIgnoreCase)
                    .ToImmutableArray();
                var byAsset = new Dictionary<string, EntityKnowledge>(StringComparer.OrdinalIgnoreCase);
                foreach (var entity in allEntities)
                {
                    byAsset[entity.AssetName] = entity;
                    foreach (var alias in entity.Aliases)
                    {
                        byAsset[alias] = entity;
                    }
                }
                var byFaction = builtin.ToImmutableDictionary(
                    kv => kv.Key,
                    kv => kv.Value.Values.OrderBy(e => e.AssetName, StringComparer.OrdinalIgnoreCase).ToImmutableArray(),
                    StringComparer.OrdinalIgnoreCase);
                var unknownTagsArray = unknownTags.OrderBy(x => x, StringComparer.OrdinalIgnoreCase).ToImmutableArray();
                if (!unknownTagsArray.IsEmpty)
                {
                    System.Diagnostics.Debug.WriteLine(
                        $"[AiKnowledge] 未知标签（{modName}）：{string.Join(", ", unknownTagsArray)}");
                }

                return new StructuredKnowledge(
                    byAsset.ToImmutableDictionary(StringComparer.OrdinalIgnoreCase),
                    allEntities,
                    byFaction,
                    unknownTagsArray);
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine($"[AiKnowledge] Failed to load knowledge_units_{modName}.json: {ex.Message}");
                return null;
            }
        }

        /// <summary>
        /// 解析知识 JSON 的 factions 结构，返回 faction → (assetName → EntityKnowledge)；
        /// 同时收集未知标签。
        /// </summary>
        private static Dictionary<string, Dictionary<string, EntityKnowledge>>? ParseFactions(
            string path,
            out HashSet<string> unknownTags)
        {
            var unknownTagsLocal = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
            var json = File.ReadAllText(path, Encoding.UTF8);
            using var doc = JsonDocument.Parse(json);
            var root = doc.RootElement;
            if (!root.TryGetProperty("factions", out var factions))
            {
                unknownTags = unknownTagsLocal;
                return null;
            }

            var result = new Dictionary<string, Dictionary<string, EntityKnowledge>>(StringComparer.OrdinalIgnoreCase);
            foreach (var faction in factions.EnumerateObject())
            {
                var factionName = faction.Name;
                if (!result.TryGetValue(factionName, out var entries))
                {
                    entries = new Dictionary<string, EntityKnowledge>(StringComparer.OrdinalIgnoreCase);
                    result[factionName] = entries;
                }

                void AddEntity(JsonElement el, bool isBuilding)
                {
                    var assetName = GetString(el, "assetName") ?? "unknown";
                    var tags = GetStringArray(el, "tags");
                    foreach (var tag in tags)
                    {
                        if (!KnowledgeTag.All.Contains(tag, StringComparer.OrdinalIgnoreCase))
                        {
                            unknownTagsLocal.Add(tag);
                        }
                    }
                    var producedBy = GetStringArray(el, "producedBy");
                    var alsoProducedBy = GetStringArray(el, "alsoProducedBy");
                    var combinedProducedBy = producedBy
                        .Concat(alsoProducedBy)
                        .Distinct(StringComparer.OrdinalIgnoreCase)
                        .ToImmutableArray();
                    var ek = new EntityKnowledge(
                        assetName,
                        GetString(el, "displayName") ?? "",
                        factionName,
                        isBuilding ? null : GetString(el, "tier"),
                        tags,
                        ParseSpecialPowers(el),
                        isBuilding ? ImmutableArray<string>.Empty : combinedProducedBy,
                        GetStringArray(el, "aliases"),
                        GetString(el, "text") ?? "");
                    entries[assetName] = ek;
                }

                if (faction.Value.TryGetProperty("buildings", out var bldgs))
                {
                    foreach (var b in bldgs.EnumerateArray())
                    {
                        AddEntity(b, isBuilding: true);
                    }
                }
                if (faction.Value.TryGetProperty("units", out var units))
                {
                    foreach (var u in units.EnumerateArray())
                    {
                        AddEntity(u, isBuilding: false);
                    }
                }
            }
            unknownTags = unknownTagsLocal;
            return result;
        }

        private static string? GetString(JsonElement el, string prop) =>
            el.TryGetProperty(prop, out var v) && v.ValueKind == JsonValueKind.String
                ? v.GetString()
                : null;

        private static ImmutableArray<string> GetStringArray(JsonElement el, string prop)
        {
            if (!el.TryGetProperty(prop, out var arr) || arr.ValueKind != JsonValueKind.Array)
                return ImmutableArray<string>.Empty;
            var result = new List<string>();
            foreach (var item in arr.EnumerateArray())
            {
                if (item.ValueKind == JsonValueKind.String && item.GetString() is { } s)
                    result.Add(s);
            }
            return result.ToImmutableArray();
        }

        private static ImmutableArray<SpecialPowerInfo> ParseSpecialPowers(JsonElement el)
        {
            if (!el.TryGetProperty("specialPowers", out var arr) || arr.ValueKind != JsonValueKind.Array)
                return ImmutableArray<SpecialPowerInfo>.Empty;
            var result = new List<SpecialPowerInfo>();
            foreach (var item in arr.EnumerateArray())
            {
                if (item.ValueKind != JsonValueKind.Object) continue;
                var name = GetString(item, "name") ?? "";
                var desc = GetString(item, "description") ?? "";
                if (!string.IsNullOrWhiteSpace(name))
                    result.Add(new SpecialPowerInfo(name, desc));
            }
            return result.ToImmutableArray();
        }
    }

    /// <summary>
    /// A named collection of game knowledge entries for a specific game version (mod).
    /// Entries are organized by scope; the set is self-contained and complete for its mod.
    /// </summary>
    internal sealed class KnowledgeSet
    {
        private readonly ImmutableArray<(KnowledgeScope Scope, KnowledgeEntry Entry)> _entries;

        public KnowledgeSet(IEnumerable<(KnowledgeScope Scope, KnowledgeEntry Entry)> entries)
        {
            _entries = entries.ToImmutableArray();
        }

        // ── Query helpers ────────────────────────────────────────────

        public ImmutableArray<KnowledgeEntry> ByScope(KnowledgeScopeKind kind, string? name = null) =>
            _entries
                .Where(e => e.Scope.Kind == kind
                    && (name is null || string.Equals(e.Scope.Name, name, StringComparison.OrdinalIgnoreCase)))
                .Select(e => e.Entry)
                .ToImmutableArray();

        public ImmutableArray<KnowledgeEntry> ByTag(string tag) =>
            _entries
                .Where(e => e.Entry.HasTag(tag))
                .Select(e => e.Entry)
                .ToImmutableArray();

        public ImmutableArray<KnowledgeEntry> ByAnyTag(params string[] tags) =>
            _entries
                .Where(e => e.Entry.HasAnyTag(tags))
                .Select(e => e.Entry)
                .ToImmutableArray();

        // ── Prompt rendering ─────────────────────────────────────────

        public string RenderAsPrompt(IReadOnlyList<string> factionNames, string? mapId)
        {
            var sb = new StringBuilder();

            foreach (var entry in ByScope(KnowledgeScopeKind.Global))
            {
                var text = entry.Id.StartsWith("knowledge-text-", StringComparison.Ordinal)
                    ? FilterFlatTextByFactions(entry.Text, factionNames)
                    : entry.Text;
                sb.AppendLine(text.Trim());
                sb.AppendLine();
            }

            foreach (var faction in factionNames)
            {
                foreach (var entry in ByScope(KnowledgeScopeKind.Faction, faction))
                {
                    sb.AppendLine(entry.Text.Trim());
                    sb.AppendLine();
                }
            }

            if (mapId is not null)
            {
                foreach (var entry in ByScope(KnowledgeScopeKind.Map, mapId))
                {
                    sb.AppendLine(entry.Text.Trim());
                    sb.AppendLine();
                }
            }

            return sb.ToString().Replace("\r", "");
        }

        private static readonly (string Faction, string StartMarker)[] FactionSectionMarkers =
        {
            ("盟军", "盟军常用建筑与升级"),
            ("神州", "神州常用建筑"),
        };

        /// <summary>flat 文本按参战阵营过滤：只保留全局部分与参战阵营的章节，减少 token 浪费。</summary>
        private static string FilterFlatTextByFactions(string text, IReadOnlyList<string> factionNames)
        {
            if (factionNames.Count == 0)
            {
                return text;
            }
            var participating = new HashSet<string>(factionNames, StringComparer.OrdinalIgnoreCase);
            var lines = text.Replace("\r", "").Split('\n');
            var sb = new StringBuilder();
            string? currentFaction = null;
            foreach (var raw in lines)
            {
                var line = raw.TrimStart();
                var matched = FactionSectionMarkers.FirstOrDefault(
                    m => line.StartsWith(m.StartMarker, StringComparison.OrdinalIgnoreCase));
                if (matched.Faction is not null)
                {
                    currentFaction = matched.Faction;
                    if (participating.Contains(currentFaction))
                    {
                        sb.AppendLine(raw);
                    }
                    continue;
                }
                if (line.StartsWith("# 地图参数", StringComparison.OrdinalIgnoreCase))
                {
                    currentFaction = null;
                }
                if (currentFaction is null || participating.Contains(currentFaction))
                {
                    sb.AppendLine(raw);
                }
            }
            return sb.ToString().TrimEnd();
        }

        // ── Built-in factory ─────────────────────────────────────────

        /// <summary>
        /// Create a built-in KnowledgeSet for a given mod name.
        /// Loads text from <c>knowledge_{modName}.md</c> and structured entries
        /// from <c>knowledge_units.json</c>. The flat text's unit/building
        /// sections are stripped and replaced by structured entries for rendering.
        /// </summary>
        public static KnowledgeSet ForMod(string modName, string? baseDirectory = null)
        {
            var searchDir = baseDirectory ?? AppContext.BaseDirectory;
            var entries = new List<(KnowledgeScope Scope, KnowledgeEntry Entry)>();
            var structured = StructuredKnowledge.GetForMod(modName);

            // 1. Load flat text from knowledge_{modName}.md
            var flatPath = Path.Combine(searchDir, $"knowledge_{modName}.md");
            string? flatText = null;
            if (File.Exists(flatPath))
            {
                flatText = File.ReadAllText(flatPath, Encoding.UTF8);
            }

            // 2. If structured data is available, strip unit sections from flat text
            //    and add structured entries as faction-scoped KnowledgeEntry.
            if (structured is not null && flatText is not null)
            {
                var cleaned = StripUnitSections(flatText, structured);
                entries.Add((KnowledgeScope.Global, new KnowledgeEntry(
                    $"knowledge-text-{modName}",
                    ImmutableArray.Create("rule"),
                    cleaned)));

                foreach (var kv in structured.EntitiesByFaction)
                {
                    var factionName = kv.Key;
                    var sb = new StringBuilder();
                    sb.AppendLine($"# {factionName}");

                    // Buildings (entities with structure tag)
                    var bldgs = kv.Value
                        .Where(e => e.IsBuilding)
                        .ToImmutableArray();
                    if (!bldgs.IsEmpty)
                    {
                        sb.AppendLine("## 建筑与升级");
                        foreach (var b in bldgs)
                        {
                            sb.Append("- ");
                            sb.Append(b.DisplayName);
                            sb.Append('(');
                            sb.Append(b.AssetName);
                            sb.Append(")：");
                            sb.AppendLine(b.Text.Trim());
                        }
                        sb.AppendLine();
                    }

                    // Units (entities without structure tag) by tier
                    var units = kv.Value
                        .Where(e => e.IsUnit)
                        .GroupBy(u => u.Tier ?? "")
                        .OrderBy(g => TierOrder(g.Key));
                    foreach (var tier in units)
                    {
                        var label = tier.Key switch
                        {
                            "基础" => "基础单位",
                            "T2" => "T2 单位（需要T2升级）",
                            "T3" => "T3 单位（需要T3升级）",
                            "T4" => "T4 单位（需要T4升级）",
                            _ => tier.Key,
                        };
                        sb.AppendLine($"## {label}");
                        foreach (var unit in tier)
                        {
                            sb.Append("- ");
                            sb.Append(unit.DisplayName);
                            sb.Append('(');
                            sb.Append(unit.AssetName);
                            sb.AppendLine(")");

                            // Type info from tags
                            var typeTags = unit.Tags
                                .Where(t => t is "vehicle" or "infantry" or "aircraft" or "naval" or "structure" or "hero" or "amphibious")
                                .Select(TagDisplayName);
                            if (typeTags.Any())
                            {
                                sb.Append("  - 类型: ");
                                sb.AppendLine(string.Join("、", typeTags));
                            }

                            // Special powers
                            if (!unit.SpecialPowers.IsEmpty)
                            {
                                foreach (var sp in unit.SpecialPowers)
                                {
                                    sb.Append("  - 技能: ");
                                    sb.Append(sp.Name);
                                    if (!string.IsNullOrWhiteSpace(sp.Description))
                                    {
                                        sb.Append(" — ");
                                        sb.Append(sp.Description);
                                    }
                                    sb.AppendLine();
                                }
                            }

                            // Produced by
                            if (!unit.ProducedBy.IsEmpty)
                            {
                                var producerNames = unit.ProducedBy
                                    .Select(name => structured.GetDisplayName(name) ?? name)
                                    .ToImmutableArray();
                                sb.Append("  - 生产: ");
                                sb.AppendLine(string.Join("、", producerNames));
                            }

                            // Remaining description
                            if (!string.IsNullOrWhiteSpace(unit.Text))
                            {
                                sb.Append("  - 描述: ");
                                sb.AppendLine(unit.Text.Trim());
                            }
                        }
                        sb.AppendLine();
                    }

                    entries.Add((KnowledgeScope.Faction(factionName), new KnowledgeEntry(
                        $"structured-{factionName}",
                        ImmutableArray.Create("faction", "structured"),
                        sb.ToString().TrimEnd())));
                }
            }
            else if (flatText is not null)
            {
                entries.Add((KnowledgeScope.Global, new KnowledgeEntry(
                    $"knowledge-file-{modName}",
                    ImmutableArray.Create("rule"),
                    flatText)));
            }
            else
            {
                entries.Add((KnowledgeScope.Global, new KnowledgeEntry(
                    "knowledge-unavailable",
                    ImmutableArray.Create("rule"),
                    $"# 注意\n\n游戏知识文件 knowledge_{modName}.md 未找到。\n\n")));
            }

            return new KnowledgeSet(entries);
        }

        private static int TierOrder(string tier) => tier switch
        {
            "基础" => 0,
            "T2" => 1,
            "T3" => 2,
            "T4" => 3,
            _ => 99,
        };

        private static string TagDisplayName(string tag) => tag switch
        {
            "vehicle" => "载具",
            "infantry" => "步兵",
            "aircraft" => "飞行器",
            "naval" => "海军",
            "structure" => "建筑",
            "hero" => "英雄",
            "amphibious" => "两栖",
            _ => tag,
        };

        /// <summary>
        /// Strip unit and building sections from flat text for factions that
        /// have structured data, to avoid duplication when rendering.
        /// </summary>
        private static string StripUnitSections(string flatText, StructuredKnowledge structured)
        {
            var stripMarkers = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);

            foreach (var factionName in structured.EntitiesByFaction.Keys)
            {
                var (buildingHeader, nextHeader) = factionName switch
                {
                    "盟军" => ("盟军常用建筑与升级", "盟军常用开局"),
                    "神州" => ("神州常用建筑", "神州常用开局"),
                    _ => ((string?)null, (string?)null),
                };

                if (buildingHeader is not null && nextHeader is not null)
                {
                    stripMarkers[buildingHeader] = nextHeader;
                }
            }

            if (stripMarkers.Count == 0) return flatText;

            var lines = flatText.Replace("\r", "").Split('\n');
            var result = new List<string>();
            var skipping = false;
            var currentStopMarker = (string?)null;

            foreach (var line in lines)
            {
                var trimmed = line.TrimStart();

                if (skipping)
                {
                    if (currentStopMarker is not null &&
                        trimmed.StartsWith(currentStopMarker, StringComparison.OrdinalIgnoreCase))
                    {
                        skipping = false;
                        result.Add(line);
                    }
                    continue;
                }

                var matched = stripMarkers.Keys.FirstOrDefault(
                    m => trimmed.StartsWith(m, StringComparison.OrdinalIgnoreCase));
                if (matched is not null)
                {
                    skipping = true;
                    currentStopMarker = stripMarkers[matched];
                    continue;
                }

                result.Add(line);
            }

            return string.Join("\n", result);
        }

        public static KnowledgeSet ForReplay(ReplayFile.Replay replay, string? baseDirectory = null)
        {
            var modName = replay.Mod.ModName?.ToLowerInvariant() switch
            {
                "corona" => "corona",
                _ => "default",
            };
            return ForMod(modName, baseDirectory);
        }
    }
}