#!/usr/bin/env python3
"""Apply the shared gallery presentation and lightbox behavior to mission galleries."""

from __future__ import annotations

import re
from pathlib import Path


ROOT = Path(__file__).resolve().parents[1]
WIKI_DIR = ROOT / "data" / "wiki"
GALLERY_FILES = sorted(WIKI_DIR.glob("guanghan_*_gallery_zh.html"))

STYLE_END_RE = re.compile(r"</style>", re.IGNORECASE)
SCRIPT_RE = re.compile(r"\s*<script>.*?</script>\s*", re.IGNORECASE | re.DOTALL)
ASSET_IMAGE_RE = re.compile(r"<img\b(?=[^>]*\bdata-wiki-asset=)[^>]*>", re.IGNORECASE)
CSS_BLOCK_RE = re.compile(
    r"\n?/\* mission-gallery-enhancements:start \*/.*?"
    r"/\* mission-gallery-enhancements:end \*/\n?",
    re.DOTALL,
)
LEGACY_LIGHTBOX_CSS_RE = re.compile(
    r"\n?\.wiki-article img\[data-wiki-asset\][^\n]*\n"
    r".*?@media \(max-width: 820px\) \{ \.wiki-image-lightbox \{.*?\}\s*\}\n?",
    re.DOTALL,
)

GALLERY_CSS = r"""
/* mission-gallery-enhancements:start */
.wiki-article .gallery-grid {
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 300px), 1fr));
  align-items: stretch;
}
.wiki-article .gallery-item {
  display: grid;
  grid-template-rows: auto 1fr;
  overflow: hidden;
  content-visibility: auto;
  contain-intrinsic-size: 340px 300px;
}
.wiki-article .gallery-item img[data-wiki-asset] {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: #202122;
  cursor: zoom-in;
}
.wiki-article .gallery-item .thumbcaption {
  padding: 8px 7px 7px;
}
.wiki-article .gallery-notice {
  margin: 1em 0 1.25em;
  padding: 10px 12px;
  border-left: 4px solid #36c;
  background: #f1f4fd;
  color: #202122;
}
.wiki-article .image-placeholder {
  position: relative;
  border: 1px dashed #72777d;
  background: linear-gradient(135deg, #f8f9fa, #eaecf0);
  color: #54595d;
}
.wiki-article.gallery-planning .gallery-grid {
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 360px), 1fr));
  gap: 12px;
}
.wiki-article.gallery-planning .gallery-item {
  display: block;
  content-visibility: visible;
  contain-intrinsic-size: none;
  border-color: #a2a9b1;
  background: #fff;
  box-shadow: 0 1px 2px rgba(32, 33, 34, 0.08);
}
.wiki-article.gallery-planning .image-placeholder {
  min-height: 0 !important;
  display: block;
  padding: 14px 14px 12px;
  border: 0;
  border-left: 4px solid #72777d;
  background: #f8f9fa;
  color: #202122;
  text-align: left;
  font-size: 13px;
  font-weight: 600;
  line-height: 1.65;
}
.wiki-article.gallery-planning .gallery-item .thumbcaption {
  padding: 10px 14px 12px;
  border-top: 1px solid #eaecf0;
  color: #54595d;
}
.wiki-article.gallery-planning > .image-placeholder {
  min-height: 0;
  padding: 22px 18px;
  border-left: 4px solid #72777d;
}
.wiki-image-lightbox {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: rgba(32, 33, 34, 0.88);
  z-index: 10000;
  box-sizing: border-box;
}
.wiki-image-lightbox[hidden] { display: none; }
.wiki-image-lightbox-panel {
  position: relative;
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr) 44px;
  grid-template-areas: "close close close" "prev image next" "counter caption caption";
  gap: 8px;
  width: min(1320px, 96vw);
  max-height: 94vh;
  overflow: auto;
  margin: 0;
  padding: 10px;
  border: 1px solid #a2a9b1;
  background: #fff;
  box-shadow: 0 12px 38px rgba(0, 0, 0, 0.35);
  box-sizing: border-box;
}
.wiki-image-lightbox-panel > img {
  grid-area: image;
  width: 100%;
  height: min(78vh, 900px);
  object-fit: contain;
  background: #000;
}
.wiki-image-lightbox-close {
  grid-area: close;
  justify-self: end;
  position: static;
  float: none;
  width: 34px;
  height: 34px;
  margin: 0;
  border: 1px solid #a2a9b1;
  border-radius: 3px;
  background: #eaecf0;
  color: #202122;
  font-size: 22px;
  line-height: 30px;
  cursor: pointer;
}
.wiki-image-lightbox-close:hover,
.wiki-image-lightbox-close:focus { background: #fff; }
.wiki-image-lightbox-prev { grid-area: prev; }
.wiki-image-lightbox-next { grid-area: next; }
.wiki-image-lightbox-nav {
  align-self: center;
  width: 40px;
  height: 56px;
  border: 1px solid #a2a9b1;
  border-radius: 3px;
  background: #eaecf0;
  color: #202122;
  font-size: 26px;
  cursor: pointer;
}
.wiki-image-lightbox-nav:hover,
.wiki-image-lightbox-nav:focus { background: #fff; }
.wiki-image-lightbox-counter { grid-area: counter; color: #54595d; white-space: nowrap; }
.wiki-image-lightbox-panel .thumbcaption { grid-area: caption; padding: 0 4px 3px; }
body.wiki-image-lightbox-open { overflow: hidden; }
@media (max-width: 820px) {
  .wiki-article .gallery-grid { grid-template-columns: 1fr; }
  .wiki-image-lightbox-panel {
    grid-template-columns: 36px minmax(0, 1fr) 36px;
    width: 98vw;
  }
  .wiki-image-lightbox-panel > img { height: 70vh; }
  .wiki-image-lightbox-nav { width: 34px; height: 48px; }
}
/* mission-gallery-enhancements:end */
""".strip()

GALLERY_JS = r"""<script>
(function () {
  function ready(fn) {
    if (document.readyState === 'loading') {
      document.addEventListener('DOMContentLoaded', fn, { once: true });
    } else {
      fn();
    }
  }

  function captionFor(image) {
    var container = image.closest('.gallery-item, figure, td, tr, .infobox-image');
    var caption = container && container.querySelector('.thumbcaption');
    return caption ? caption.textContent.trim() : (image.alt || '');
  }

  function install(article) {
    if (!article || article.dataset.galleryLightboxReady === '1') { return; }
    var images = Array.prototype.slice.call(article.querySelectorAll('img[data-wiki-asset]'));
    if (!images.length) { return; }
    article.dataset.galleryLightboxReady = '1';

    var overlay = document.createElement('div');
    overlay.className = 'wiki-image-lightbox';
    overlay.hidden = true;
    overlay.innerHTML = '<figure class="wiki-image-lightbox-panel" role="dialog" aria-modal="true" aria-label="任务图集图片预览">' +
      '<button class="wiki-image-lightbox-close" type="button" aria-label="关闭图片预览">×</button>' +
      '<button class="wiki-image-lightbox-nav wiki-image-lightbox-prev" type="button" aria-label="上一张">‹</button>' +
      '<img alt="">' +
      '<button class="wiki-image-lightbox-nav wiki-image-lightbox-next" type="button" aria-label="下一张">›</button>' +
      '<span class="wiki-image-lightbox-counter" aria-live="polite"></span>' +
      '<figcaption class="thumbcaption"></figcaption></figure>';
    document.body.appendChild(overlay);

    var previewImage = overlay.querySelector('img');
    var previewCaption = overlay.querySelector('figcaption');
    var counter = overlay.querySelector('.wiki-image-lightbox-counter');
    var closeButton = overlay.querySelector('.wiki-image-lightbox-close');
    var previousButton = overlay.querySelector('.wiki-image-lightbox-prev');
    var nextButton = overlay.querySelector('.wiki-image-lightbox-next');
    var activeIndex = 0;
    var lastTrigger = null;

    function render(index) {
      activeIndex = (index + images.length) % images.length;
      var image = images[activeIndex];
      previewImage.src = image.dataset.wikiAsset || image.currentSrc || image.src;
      previewImage.alt = image.alt || '';
      previewCaption.textContent = captionFor(image);
      counter.textContent = (activeIndex + 1) + ' / ' + images.length;
    }

    function closePreview() {
      overlay.hidden = true;
      previewImage.removeAttribute('src');
      document.body.classList.remove('wiki-image-lightbox-open');
      if (lastTrigger) { lastTrigger.focus(); }
    }

    function openPreview(image, event) {
      if (event) { event.preventDefault(); event.stopPropagation(); }
      lastTrigger = image;
      render(images.indexOf(image));
      overlay.hidden = false;
      document.body.classList.add('wiki-image-lightbox-open');
      closeButton.focus();
    }

    images.forEach(function (image) {
      image.tabIndex = 0;
      image.setAttribute('role', 'button');
      image.setAttribute('aria-label', '打开图片预览：' + (image.alt || '任务影像'));
      image.addEventListener('click', function (event) { openPreview(image, event); });
      image.addEventListener('keydown', function (event) {
        if (event.key === 'Enter' || event.key === ' ') { openPreview(image, event); }
      });
    });

    previousButton.hidden = images.length < 2;
    nextButton.hidden = images.length < 2;
    previousButton.addEventListener('click', function () { render(activeIndex - 1); });
    nextButton.addEventListener('click', function () { render(activeIndex + 1); });
    closeButton.addEventListener('click', closePreview);
    overlay.addEventListener('click', function (event) {
      if (event.target === overlay) { closePreview(); }
    });
    document.addEventListener('keydown', function (event) {
      if (overlay.hidden) { return; }
      if (event.key === 'Escape') { closePreview(); }
      if (event.key === 'ArrowLeft') { render(activeIndex - 1); }
      if (event.key === 'ArrowRight') { render(activeIndex + 1); }
    });
  }

  ready(function () {
    Array.prototype.forEach.call(document.querySelectorAll('.wiki-article'), install);
  });
}());
</script>"""


def add_image_loading_attributes(match: re.Match[str]) -> str:
    tag = match.group(0)
    additions = []
    if not re.search(r"\bloading=", tag, re.IGNORECASE):
        additions.append('loading="lazy"')
    if not re.search(r"\bdecoding=", tag, re.IGNORECASE):
        additions.append('decoding="async"')
    if not re.search(r"\bfetchpriority=", tag, re.IGNORECASE):
        additions.append('fetchpriority="low"')
    if not additions:
        return tag
    return tag[:-1].rstrip() + " " + " ".join(additions) + ">"


def normalize(path: Path) -> bool:
    original = path.read_text(encoding="utf-8")
    updated = LEGACY_LIGHTBOX_CSS_RE.sub("\n", original)
    updated = CSS_BLOCK_RE.sub("\n", updated)
    updated = STYLE_END_RE.sub(GALLERY_CSS + "\n</style>", updated, count=1)
    updated = ASSET_IMAGE_RE.sub(add_image_loading_attributes, updated)

    updated = SCRIPT_RE.sub("\n", updated).rstrip()
    updated += "\n"

    if updated == original:
        return False
    path.write_text(updated, encoding="utf-8", newline="\n")
    return True


def main() -> int:
    changed = 0
    for path in GALLERY_FILES:
        was_changed = normalize(path)
        changed += int(was_changed)
        print(f"gallery_normalized file={path.name} changed={str(was_changed).lower()}")
    print(f"gallery_normalized_summary files={len(GALLERY_FILES)} changed={changed}")
    return 0


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