#!/usr/bin/env python3
from __future__ import annotations

import json
import sys
from pathlib import Path

ROOT = Path(__file__).resolve().parents[1]
if hasattr(sys.stdout, "reconfigure"):
    sys.stdout.reconfigure(encoding="utf-8", errors="replace")
if hasattr(sys.stderr, "reconfigure"):
    sys.stderr.reconfigure(encoding="utf-8", errors="replace")
BASELINE_PATH = ROOT / "docs" / "engineering" / "size-baseline.json"
ENVS = ["production", "debug", "test"]


def file_size(path: Path) -> int:
    return path.stat().st_size if path.exists() else -1


def main() -> int:
    if not BASELINE_PATH.exists():
        print(f"Missing size baseline: {BASELINE_PATH.relative_to(ROOT)}")
        return 1

    baseline = json.loads(BASELINE_PATH.read_text(encoding="utf-8"))
    baseline_envs = baseline.get("environments", {})
    errors: list[str] = []

    print("Firmware size report:")
    for env in ENVS:
        build_dir = ROOT / ".pio" / "build" / env
        bin_path = build_dir / "firmware.bin"
        elf_path = build_dir / "firmware.elf"
        bin_size = file_size(bin_path)
        elf_size = file_size(elf_path)
        if bin_size < 0 or elf_size < 0:
            errors.append(f"{env}: missing firmware artifacts; run python -m platformio run -e {env}")
            continue
        entry = baseline_envs.get(env)
        if not entry:
            errors.append(f"{env}: missing baseline entry")
            continue
        baseline_bin = int(entry["firmware_bin_bytes"])
        max_bin = int(entry.get("max_firmware_bin_bytes", baseline_bin))
        delta = bin_size - baseline_bin
        print(
            f"- {env}: firmware.bin={bin_size} bytes "
            f"(baseline {baseline_bin}, delta {delta:+}), firmware.elf={elf_size} bytes"
        )
        if bin_size > max_bin:
            errors.append(f"{env}: firmware.bin {bin_size} exceeds limit {max_bin}")

    if errors:
        for error in errors:
            print(f"ERROR: {error}")
        return 1
    return 0


if __name__ == "__main__":
    raise SystemExit(main())