card-game-engine/RuleEngine/AI/HumanMahjongPlayer.cs

namespace RuleEngine.AI;

using RuleEngine.Core;
using RuleEngine.Phase;
using RuleEngine.Patterns;

/// <summary>
/// Human player — reads commands from console stdin.
/// Commands: h=hu, p=pung, k=kong (an_kong/ming_kong/bu_kong), c=chi, 1-N=discard by index, q=quit
/// </summary>
public class HumanMahjongPlayer
{
    public string Name { get; }
    private readonly MeldsSolver _solver;
    private readonly bool _includeHonors;

    public HumanMahjongPlayer(string name, MeldsSolver solver, bool includeHonors = false)
    {
        Name = name;
        _solver = solver;
        _includeHonors = includeHonors;
    }

    public (string action, int? tile) Decide(List<ActionOption> legalActions, MahjongGameState state)
    {
        var hand = state.Hands.GetValueOrDefault(Name, new List<int>());
        var sorted = hand.OrderBy(t => t).ToList();

        int? drawnTile = state.LastDrawnTile;
        int drawnIdx = drawnTile.HasValue ? sorted.IndexOf(drawnTile.Value) : -1;

        while (true)
        {
            Console.WriteLine();
            Console.WriteLine($"=== {Name} 的回合 ===");
            Console.WriteLine($"  牌墙: {state.Deck.Count}张 | 弃牌堆: {state.DiscardPool.Count}张");

            // Show wildcard info
                        var wcTiles = state.Wildcards.ConfiguredWildcards;
                        if (wcTiles.Count > 0)
                        {
                            var wcDisplay = string.Join(" ", wcTiles.Select(t => MahjongTile.ToString(t, state.Wildcards)));
                            if (state.Wildcards.RevealedTile.HasValue)
                                Console.WriteLine($"  🀫 精: {wcDisplay} (翻牌: {MahjongTile.ToString(state.Wildcards.RevealedTile.Value)})");
                            else
                                Console.WriteLine($"  🀫 宝牌(癞子): {wcDisplay}");
                        }

            // Show opponent summary
            Console.Write("  对手: ");
            var parts = new List<string>();
            foreach (var op in state.PlayerOrder)
            {
                if (op == Name || !state.AlivePlayers.Contains(op)) continue;
                var opHand = state.Hands[op];
                var opExposed = "";
                if (state.Exposed.TryGetValue(op, out var melds) && melds.Count > 0)
                    opExposed = $" 已{melds.Count}副";
                var opDiscards = "";
                if (state.DiscardHistory.TryGetValue(op, out var dh) && dh.Count > 0)
                    opDiscards = $" 出:{string.Join("", dh.TakeLast(5).Select(MahjongTile.ToString))}";
                parts.Add($"{op}:{opHand.Count}张{opExposed}{opDiscards}");
            }
            Console.WriteLine(string.Join(" | ", parts));

            // Show exposed melds
            if (state.Exposed.TryGetValue(Name, out var exposed) && exposed.Count > 0)
            {
                var meldStr = string.Join(" ", exposed.Select(m =>
                    $"{m.Type}[{string.Join(",", m.Tiles.Where(t => t != -1).Select(MahjongTile.ToString))}]"));
                Console.WriteLine($"  已碰/杠: {meldStr}");
            }

            if (drawnTile.HasValue && drawnIdx >= 0)
                Console.WriteLine($"  🀫 刚刚摸到: {MahjongTile.ToString(drawnTile.Value, state.Wildcards)}");
            Console.WriteLine($"  手牌 ({hand.Count}张):");
            for (int i = 0; i < sorted.Count; i++)
            {
                bool isDrawn = (i == drawnIdx);
                Console.WriteLine($"    [{i + 1}] {(isDrawn ? "→ " : "  ")}{MahjongTile.ToString(sorted[i], state.Wildcards)}{(isDrawn ? " ← 新摸" : "")}");
            }
            Console.WriteLine();

            // Show available actions
            var winOpt = legalActions.FirstOrDefault(a => a.Action == "win");
            var pungOpt = legalActions.FirstOrDefault(a => a.Action == "pung");
            var kongOpts = legalActions.Where(a => a.Action is "ming_kong" or "an_kong" or "bu_kong").ToList();

            // Check if we're one tile away from winning (ting) — returns list of winning tiles
            var tingTiles = GetTingTiles(state);

            Console.Write("  可选操作: ");
            var ops = new List<string>();
            if (hand.Count > 0) ops.Add($"1-{hand.Count}(出牌)");
            if (pungOpt != null) ops.Add("p(碰)");
            if (kongOpts.Count > 0) ops.Add($"k(杠: {string.Join("/", kongOpts.Select(o => o.Action))})");
            if (winOpt != null) ops.Add("h✨(胡!)");
            if (tingTiles.Count > 0)
            {
                var names = tingTiles.Select(t => MahjongTile.ToString(t, state.Wildcards));
                ops.Add($"🀄听 {tingTiles.Count}张({string.Join(" ", names)})");
            }
            ops.Add("q(退出)");
            Console.WriteLine(string.Join(" ", ops));
            Console.Write("> ");

            string? input = Console.ReadLine()?.Trim().ToLower();
            if (string.IsNullOrEmpty(input)) continue;

            if (input == "q") return ("pass", null);
            if (input == "h" && winOpt != null) return ("win", null);
            if (input == "p" && pungOpt != null) return ("pung", null);
            if (input == "k" && kongOpts.Count > 0) return (kongOpts[0].Action, null);

            if (int.TryParse(input, out int idx) && idx >= 1 && idx <= sorted.Count)
                return ("discard", sorted[idx - 1]);

            Console.WriteLine("  无效输入，请重试");
        }
    }

    private List<int> GetTingTiles(MahjongGameState state)
    {
        var result = new List<int>();
        var hand = state.Hands.GetValueOrDefault(Name, new List<int>());
        // Combine with exposed melds
        var fullHand = new List<int>(hand);
        if (state.Exposed.TryGetValue(Name, out var melds))
            foreach (var m in melds)
                fullHand.AddRange(m.Tiles.Where(t => t != -1));

        // Check all possible tiles for win potential
        var allTiles = MahjongTile.AllTiles(_includeHonors, false);
        int wc = state.Wildcards.CountWildcards(fullHand);
        foreach (var tile in allTiles)
        {
            if (hand.Count(t => t == tile) >= 4) continue;
            var r = _solver.CheckWin(fullHand, newTile: tile, wildcardCount: wc);
            if (r != null && r.IsWin) result.Add(tile);
        }
        return result;
    }
}