"""ModelTranslator CLI：FBX -> 纯模型 FBX + XPbr 贴图 + Unity .mat/.meta。
用法：python model_translator.py src/tong.fbx [-o out] [--max-size 2048] [--blender exe]
"""
import argparse
import json
import os
import sys

import unity_assets as ua
from mt_run import HERE, find_blender, run_blender_script
from png_compress import compress_dir_pngs


def write_unity_assets(outdir, summary, max_size):
    remaps = []
    for m in summary["materials"]:
        base_png = os.path.join(outdir, m["base_png"])
        mix_png = os.path.join(outdir, m["mix_png"])
        base_guid = ua.guid_for(base_png)
        mix_guid = ua.guid_for(mix_png)
        alpha_test = m["alpha_mode"] == "transparency"
        with open(base_png + ".meta", "w", encoding="utf-8", newline="\n") as f:
            f.write(
                ua.texture_meta(
                    base_guid,
                    srgb=True,
                    max_size=max_size,
                    alpha_is_transparency=alpha_test,
                )
            )
        with open(mix_png + ".meta", "w", encoding="utf-8", newline="\n") as f:
            f.write(ua.texture_meta(mix_guid, srgb=False, max_size=max_size))

        mat_name = (
            summary["model"]
            if m["safe_name"] == summary["model"]
            else "%s_%s" % (summary["model"], m["safe_name"])
        )
        mat_path = os.path.join(outdir, mat_name + ".mat")
        mat_guid = ua.guid_for(mat_path)
        with open(mat_path, "w", encoding="utf-8", newline="\n") as f:
            f.write(
                ua.material_yaml(
                    mat_name, ua.XPBR_SHADER_GUID, base_guid, mix_guid, alpha_test
                )
            )
        with open(mat_path + ".meta", "w", encoding="utf-8", newline="\n") as f:
            f.write(ua.material_meta(mat_guid))
        remaps.append((m["name"], mat_guid))

    fbx_path = os.path.join(outdir, summary["fbx"])
    fbx_guid = ua.guid_for(fbx_path)
    with open(fbx_path + ".meta", "w", encoding="utf-8", newline="\n") as f:
        f.write(ua.model_meta(fbx_guid, remaps))
    return {
        "fbx": fbx_path,
        "fbx_guid": fbx_guid,
        "materials": remaps,
        "outdir": outdir,
    }


def report(summary, outdir):
    print("== %s -> %s" % (summary["model"], outdir))
    for m in summary["materials"]:
        print(
            "  材质 %-24s A通道=%s 尺寸=%dx%d"
            % (m["name"], m["alpha_mode"], m["size"][0], m["size"][1])
        )
        for k, v in m["sources"].items():
            print("    %-10s %s" % (k, v or "(常量)"))
        for w in m["warnings"]:
            print("    [警告] %s" % w)


def translate_fbx(src, outdir, max_size=2048, blender=None):
    """Convert bake-output FBX (+ sibling PBR maps) into XPbr assets. Returns summary dict."""
    blender_exe = find_blender(blender)
    os.makedirs(outdir, exist_ok=True)
    summary = run_blender_script(
        blender_exe, "bl_convert.py", [src, outdir, str(max_size)]
    )
    compress_dir_pngs(outdir, suffixes=("_base.png", "_mix.png"))
    unity = write_unity_assets(outdir, summary, max_size)
    return {**summary, "unity": unity}


def main():
    ap = argparse.ArgumentParser(description=__doc__)
    ap.add_argument("input", help="FBX 文件或目录")
    ap.add_argument("-o", "--out", default=os.path.join(HERE, "out_xpbr"))
    ap.add_argument("--max-size", type=int, default=2048)
    ap.add_argument("--blender", default=None)
    args = ap.parse_args()

    if os.path.isdir(args.input):
        srcs = [
            os.path.join(args.input, f)
            for f in sorted(os.listdir(args.input))
            if f.lower().endswith(".fbx")
        ]
        if not srcs:
            sys.exit("目录中没有 FBX：%s" % args.input)
    else:
        srcs = [args.input]

    for src in srcs:
        name = os.path.splitext(os.path.basename(src))[0]
        outdir = os.path.join(args.out, name)
        summary = translate_fbx(src, outdir, args.max_size, args.blender)
        report(summary, outdir)


if __name__ == "__main__":
    main()