#!/usr/bin/env python3
import os
import sys
import glob
import subprocess
import concurrent.futures

def main():
    cc = sys.argv[1] if len(sys.argv) > 1 else "gcc"
    cflags_str = sys.argv[2] if len(sys.argv) > 2 else ""
    build_dir = sys.argv[3] if len(sys.argv) > 3 else "build"

    cflags = [f for f in cflags_str.split() if f]
    lvgl_obj_dir = os.path.join(build_dir, "lvgl")
    target_lib = os.path.join(build_dir, "liblvgl.a")

    srcs = sorted(glob.glob("lib/lvgl/src/**/*.c", recursive=True))
    tasks = []

    for src in srcs:
        rel = os.path.relpath(src, "lib/lvgl")
        obj = os.path.join(lvgl_obj_dir, os.path.splitext(rel)[0] + ".o")
        os.makedirs(os.path.dirname(obj), exist_ok=True)
        tasks.append((src, obj))

    def compile_task(item):
        src, obj = item
        if not os.path.exists(obj) or os.path.getmtime(src) > os.path.getmtime(obj):
            cmd = [cc] + cflags + ["-Ilib/lvgl", "-O2", "-c", src, "-o", obj]
            res = subprocess.run(cmd, capture_output=True, text=True)
            if res.returncode != 0:
                print(f"[ERR] Failed to compile {src}:\n{res.stderr}", file=sys.stderr)
                return False
        return True

    cpu_count = min(os.cpu_count() or 4, 16)
    with concurrent.futures.ThreadPoolExecutor(max_workers=cpu_count) as ex:
        results = list(ex.map(compile_task, tasks))

    if not all(results):
        sys.exit(1)

    all_objs = [obj for _, obj in tasks]
    subprocess.run(["ar", "rcs", target_lib] + all_objs, check=True)

if __name__ == "__main__":
    main()