using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using AcDream.Bake;

// acdream-bake: offline CLI producing a versioned pak file containing every
// ObjectMeshData the client's decode workers would otherwise produce at
// runtime (GfxObj / Setup / EnvCell mesh+texture payloads).
//
// Thin arg-parsing shell over BakeRunner (the real pipeline lives there so
// the dat-gated byte-reproducibility test can drive it directly).
//
// Plan: docs/superpowers/plans/2026-07-05-mp1b-pak-and-bake.md, Task 5.

string? datDir = null;
string? outPath = null;
HashSet<uint>? idFilter = null;
HashSet<uint>? landblockFilter = null;
int threads = Environment.ProcessorCount;

for (int i = 0; i < args.Length; i++) {
    switch (args[i]) {
        case "--dat-dir":
            datDir = args.ElementAtOrDefault(++i);
            break;
        case "--out":
            outPath = args.ElementAtOrDefault(++i);
            break;
        case "--ids":
            idFilter = ParseHexList(args.ElementAtOrDefault(++i));
            break;
        case "--landblocks":
            landblockFilter = ParseHexList(args.ElementAtOrDefault(++i));
            break;
        case "--threads":
            if (int.TryParse(args.ElementAtOrDefault(++i), out var t) && t > 0) threads = t;
            break;
        default:
            Console.Error.WriteLine($"unrecognized argument: {args[i]}");
            return 2;
    }
}

if (string.IsNullOrWhiteSpace(datDir)) {
    Console.Error.WriteLine("usage: acdream-bake --dat-dir <path> [--out <file>] [--ids 0xId,0xId,...] [--landblocks 0xId,...] [--threads <n>]");
    return 2;
}

if (!Directory.Exists(datDir)) {
    Console.Error.WriteLine($"error: directory not found: {datDir}");
    return 2;
}

outPath ??= Path.Combine(datDir, "acdream.pak");

return BakeRunner.Run(new BakeOptions {
    DatDir = datDir,
    OutPath = outPath,
    IdFilter = idFilter,
    LandblockFilter = landblockFilter,
    Threads = threads,
});

static HashSet<uint> ParseHexList(string? raw) {
    var result = new HashSet<uint>();
    if (string.IsNullOrWhiteSpace(raw)) return result;
    foreach (var token in raw.Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)) {
        var hex = token.StartsWith("0x", StringComparison.OrdinalIgnoreCase) ? token[2..] : token;
        if (uint.TryParse(hex, System.Globalization.NumberStyles.HexNumber, null, out var value)) {
            result.Add(value);
        }
        else {
            Console.Error.WriteLine($"warning: could not parse id '{token}' — skipped");
        }
    }
    return result;
}