#!/usr/bin/env python3
"""Create responsive image variants and patch existing HTML img tags."""

from __future__ import annotations

import argparse
import os
import re
import sys
from pathlib import Path

from generate import log, write_text_atomic
from images import create_responsive_variants, iter_source_images

HERO_IMG_RE = re.compile(
    r'<img src="/img/(\d{4}-\d{2}-\d{2})\.jpg" alt="([^"]*)" width="560" height="420">'
)
THUMB_IMG_RE = re.compile(
    r'<img src="/img/(\d{4}-\d{2}-\d{2})\.jpg" alt="([^"]*)" width="360" height="203" loading="lazy">'
)


def patch_html_images(path: Path, descriptors: dict[str, dict[str, str]]) -> bool:
    html = path.read_text(encoding="utf-8")
    original = html

    def replace_hero(match: re.Match[str]) -> str:
        date_iso, alt = match.group(1), match.group(2)
        image = descriptors.get(date_iso)
        if not image:
            return match.group(0)
        return (
            f'<img src="{image["src"]}" srcset="{image["srcset"]}" sizes="{image["sizes"]}" '
            f'alt="{alt}" width="560" height="420">'
        )

    def replace_thumb(match: re.Match[str]) -> str:
        date_iso, alt = match.group(1), match.group(2)
        image = descriptors.get(date_iso)
        if not image:
            return match.group(0)
        return (
            f'<img src="{image["thumb_src"]}" srcset="{image["thumb_srcset"]}" '
            f'sizes="{image["thumb_sizes"]}" alt="{alt}" width="360" height="203" loading="lazy">'
        )

    html = HERO_IMG_RE.sub(replace_hero, html)
    html = THUMB_IMG_RE.sub(replace_thumb, html)
    if html != original:
        write_text_atomic(path, html)
        log(f"patched images in {path}")
        return True
    return False


def main() -> int:
    parser = argparse.ArgumentParser(description="Create responsive hero image variants")
    parser.add_argument("--site-dir", default=None)
    args = parser.parse_args()

    repo_root = Path(__file__).resolve().parent.parent
    site_dir = Path(args.site_dir or os.environ.get("SITE_DIR", repo_root / "public"))
    img_dir = site_dir / "img"

    descriptors: dict[str, dict[str, str]] = {}
    for source in iter_source_images(img_dir):
        date_iso = source.stem
        descriptor = create_responsive_variants(img_dir, date_iso)
        if descriptor:
            descriptors[date_iso] = descriptor
            log(f"created variants for {date_iso}")

    patched = 0
    targets = [site_dir / "index.html", site_dir / "archiv" / "index.html"]
    targets.extend(sorted((site_dir / "archiv").glob("2026-*.html")))
    for path in targets:
        if path.exists():
            patched += patch_html_images(path, descriptors)

    log(f"done, {len(descriptors)} image set(s), patched {patched} html file(s)")
    return 0


if __name__ == "__main__":
    sys.exit(main())