---
import type { PostEntry } from '@/lib/content';

interface Props { posts: PostEntry[]; }
interface WeekCell { week: number; words: number; level: number; }

const { posts } = Astro.props;
const currentYear = new Date().getFullYear();
const years = Array.from({ length: 3 }, (_, index) => currentYear - 2 + index);

function countWords(source: string): number {
  const text = source
    .replace(/```[\s\S]*?```/g, '')
    .replace(/`[^`]+`/g, '')
    .replace(/!\[[^\]]*\]\([^)]*\)/g, '')
    .replace(/\[([^\]]*)\]\([^)]*\)/g, '$1')
    .replace(/<[^>]+>/g, '')
    .replace(/https?:\/\/\S+/g, '')
    .replace(/[#{*_~>`|+-]/g, ' ')
    .replace(/\s+/g, ' ')
    .trim();
  const chineseCharacters = text.match(/[\u3400-\u4dbf\u4e00-\u9fff]/g)?.length ?? 0;
  const otherWords = text
    .replace(/[\u3400-\u4dbf\u4e00-\u9fff]/g, ' ')
    .split(/\s+/)
    .filter(Boolean).length;
  return chineseCharacters + otherWords;
}

function getIsoWeek(date: Date): { year: number; week: number } {
  const utcDate = new Date(Date.UTC(date.getFullYear(), date.getMonth(), date.getDate()));
  const day = utcDate.getUTCDay() || 7;
  utcDate.setUTCDate(utcDate.getUTCDate() + 4 - day);
  const year = utcDate.getUTCFullYear();
  const yearStart = new Date(Date.UTC(year, 0, 1));
  const week = Math.ceil(((utcDate.getTime() - yearStart.getTime()) / 86_400_000 + 1) / 7);
  return { year, week };
}

function getLevel(words: number): number {
  if (words === 0) return 0;
  if (words < 1_000) return 1;
  if (words < 3_000) return 2;
  if (words < 8_000) return 3;
  return 4;
}

const wordsByWeek = new Map<string, number>();
let totalWords = 0;
for (const post of posts) {
  const words = countWords(post.body ?? '');
  totalWords += words;
  const { year, week } = getIsoWeek(post.data.pubDate);
  if (!years.includes(year)) continue;
  const key = `${year}-${week}`;
  wordsByWeek.set(key, (wordsByWeek.get(key) ?? 0) + words);
}

const yearRows = years.map((year) => ({
  year,
  weeks: Array.from({ length: 53 }, (_, index): WeekCell => {
    const week = index + 1;
    const words = wordsByWeek.get(`${year}-${week}`) ?? 0;
    return { week, words, level: getLevel(words) };
  })
}));

const totalWordsLabel = totalWords >= 10_000
  ? `${(totalWords / 10_000).toFixed(2)}W`
  : totalWords.toLocaleString('zh-CN');
---

<section class="writing-heatmap" aria-labelledby="writing-heatmap-title" data-pagefind-ignore="all">
  <header>
    <div class="writing-heading">
      <h2 id="writing-heatmap-title">写作热力图</h2>
      <p class="writing-total">自博客建立以来，已输出 <span class="writing-total-value">{totalWordsLabel}</span><span class="writing-total-label">字</span></p>
    </div>
    <div class="heatmap-legend" aria-label="写作字数：从少到多">
      <span>少</span>
      {[0, 1, 2, 3, 4].map((level) => <i class={`level-${level}`} aria-hidden="true"></i>)}
      <span>多</span>
    </div>
  </header>
  <div class="heatmap-viewport" data-heatmap-viewport>
    <div class="heatmap-scroll" aria-label="最近三年每周写作字数热力图" data-heatmap-scroll>
      <div class="heatmap-grid">
        {yearRows.map((row) => <div class="heatmap-row">
          <strong>{row.year}</strong>
          {row.weeks.map((cell) => <span
            class={`heatmap-cell level-${cell.level}`}
            aria-label={`${row.year} 年第 ${cell.week} 周，${cell.words.toLocaleString('zh-CN')} 字`}
          >
            <span class="heatmap-tooltip" role="tooltip"><span class="heatmap-tooltip-code">{row.year} W{String(cell.week).padStart(2, '0')} · {cell.words.toLocaleString('zh-CN')}</span><span class="heatmap-tooltip-label">字</span></span>
          </span>)}
        </div>)}
        <div class="week-labels" aria-hidden="true">
          <span></span>
          {Array.from({ length: 53 }, (_, index) => <span>{[1, 14, 27, 40, 53].includes(index + 1) ? `W${String(index + 1).padStart(2, '0')}` : ''}</span>)}
        </div>
      </div>
    </div>
  </div>
</section>

<script>
  let cleanupHeatmap: (() => void) | undefined;

  const initHeatmap = () => {
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    cleanupHeatmap = undefined;

    const heatmapScroll = document.querySelector<HTMLElement>('[data-heatmap-scroll]');
    if (!heatmapScroll) return;

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    const heatmapGrid = heatmapScroll.querySelector<HTMLElement>('.heatmap-grid');
    const root = document.documentElement;
    const baseRootFontSize = 16;
    let baseCellSize = 0;
    let activeTooltip: { cell: HTMLElement; tooltip: HTMLElement; placeholder: Comment } | undefined;

    const updateTooltipPosition = () => {
      if (!activeTooltip) return;
      const { cell, tooltip } = activeTooltip;
      const cellRect = cell.getBoundingClientRect();
      const tooltipRect = tooltip.getBoundingClientRect();
      const gap = 6;
      const horizontalPadding = 8;
      const left = Math.min(
        Math.max(cellRect.left + cellRect.width / 2, tooltipRect.width / 2 + horizontalPadding),
        window.innerWidth - tooltipRect.width / 2 - horizontalPadding
      );
      const fitsAbove = cellRect.top >= tooltipRect.height + gap;
      const fitsBelow = cellRect.bottom + tooltipRect.height + gap <= window.innerHeight;
      const top = fitsAbove || !fitsBelow
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        : cellRect.bottom + gap;
      tooltip.style.left = `${left}px`;
      tooltip.style.top = `${Math.max(horizontalPadding, top)}px`;
    };

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      if (!activeTooltip) return;
      const { tooltip, placeholder } = activeTooltip;
      tooltip.removeAttribute('data-heatmap-portal');
      tooltip.removeAttribute('style');
      placeholder.parentNode?.insertBefore(tooltip, placeholder);
      placeholder.remove();
      activeTooltip = undefined;
    };

    const openTooltip = (cell: HTMLElement) => {
      closeTooltip();
      const tooltip = cell.querySelector<HTMLElement>('.heatmap-tooltip');
      if (!tooltip) return;
      const placeholder = document.createComment('heatmap-tooltip');
      tooltip.replaceWith(placeholder);
      tooltip.setAttribute('data-heatmap-portal', '');
      document.body.append(tooltip);
      activeTooltip = { cell, tooltip, placeholder };
      updateTooltipPosition();
      requestAnimationFrame(() => tooltip.classList.add('is-visible'));
    };

    const heatmapCells = [...heatmapScroll.querySelectorAll<HTMLElement>('.heatmap-cell')];
    const cellListeners = heatmapCells.map((cell) => {
      const onMouseEnter = () => openTooltip(cell);
      cell.addEventListener('mouseenter', onMouseEnter);
      cell.addEventListener('mouseleave', closeTooltip);
      return { cell, onMouseEnter };
    });
    window.addEventListener('resize', updateTooltipPosition);
    window.addEventListener('scroll', updateTooltipPosition, true);

    const updateHeatmapFades = () => {
      if (!heatmapViewport || !heatmapGrid) return;
      const maxScrollLeft = Math.max(0, heatmapGrid.getBoundingClientRect().width - heatmapScroll.clientWidth);
      heatmapViewport.classList.toggle('can-scroll-left', heatmapScroll.scrollLeft > 1);
      heatmapViewport.classList.toggle('can-scroll-right', heatmapScroll.scrollLeft < maxScrollLeft - 1);
    };

    const updateHeatmapOverflow = () => {
      if (!heatmapGrid) return;
      const rootFontSize = Number.parseFloat(getComputedStyle(root).fontSize) || baseRootFontSize;
      const scale = rootFontSize / baseRootFontSize;
      const availableCellSize = (heatmapScroll.clientWidth - 3.25 * baseRootFontSize) / 53;

      if (scale <= 1.01 || baseCellSize === 0) {
        baseCellSize = Math.max(8, availableCellSize);
      }
      heatmapGrid.style.setProperty('--heatmap-cell-size', `${baseCellSize * scale}px`);
      heatmapViewport?.classList.toggle('has-overflow', heatmapGrid.getBoundingClientRect().width > heatmapScroll.clientWidth + 1);
      updateHeatmapFades();
    };

    const resizeObserver = new ResizeObserver(updateHeatmapOverflow);
    const fontScaleObserver = new MutationObserver(updateHeatmapOverflow);
    resizeObserver.observe(heatmapScroll);
    fontScaleObserver.observe(root, { attributes: true, attributeFilter: ['style'] });
    heatmapScroll.addEventListener('scroll', updateHeatmapFades, { passive: true });
    updateHeatmapOverflow();

    cleanupHeatmap = () => {
      closeTooltip();
      cellListeners.forEach(({ cell, onMouseEnter }) => {
        cell.removeEventListener('mouseenter', onMouseEnter);
        cell.removeEventListener('mouseleave', closeTooltip);
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      window.removeEventListener('resize', updateTooltipPosition);
      window.removeEventListener('scroll', updateTooltipPosition, true);
      resizeObserver.disconnect();
      fontScaleObserver.disconnect();
      heatmapScroll.removeEventListener('scroll', updateHeatmapFades);
    };
  };

  document.addEventListener('astro:page-load', initHeatmap);
  initHeatmap();
</script>

<style>
  .writing-heatmap { margin-bottom: 3.5rem; }
  .writing-heatmap header { display: flex; gap: 1rem; align-items: flex-start; justify-content: space-between; margin-bottom: 1rem; }
  .writing-heading { min-width: 0; }
  .writing-heatmap h2 { margin: 0; font-size: 1.375rem; font-weight: 400; }
  .writing-total { margin: .25rem 0 0; color: var(--color-muted); font-size: .8125rem; }
  .writing-total-value { font-family: Consolas, Menlo, Monaco, 'lucida_console', 'Liberation_Mono', 'Courier_New', 'andale_mono', monospaceX, monospace, sans-serif; }
  .writing-total-label { font-family: var(--reading-font-family); }
  .heatmap-legend { display: flex; gap: .25rem; align-items: center; padding-top: .25rem; color: var(--color-muted); font-size: .75rem; }
  .heatmap-legend i { width: .75rem; height: .75rem; }
  .heatmap-viewport { position: relative; }
  .heatmap-viewport::before,
  .heatmap-viewport::after { display: none; position: absolute; z-index: 1; top: 0; bottom: .5rem; width: 1.75rem; content: ''; pointer-events: none; }
  .heatmap-viewport::before { left: 0; background: linear-gradient(90deg, var(--color-bg) 15%, transparent); }
  .heatmap-viewport::after { right: 0; background: linear-gradient(90deg, transparent, var(--color-bg) 85%); }
  .heatmap-viewport.has-overflow.can-scroll-left::before,
  .heatmap-viewport.has-overflow.can-scroll-right::after { display: block; }
  .heatmap-scroll { overflow-x: hidden; padding: .125rem 0 .5rem; container-type: inline-size; scrollbar-width: thin; }
  .heatmap-viewport.has-overflow .heatmap-scroll { overflow-x: auto; }
  .heatmap-grid { --heatmap-label-width: 3.25rem; --heatmap-cell-size: clamp(8px, .75rem, 18px); display: grid; width: max-content; gap: 4px; }
  .heatmap-row,
  .week-labels { display: grid; grid-template-columns: var(--heatmap-label-width) repeat(53, var(--heatmap-cell-size)); column-gap: 0; row-gap: 2px; align-items: center; }
  .heatmap-row strong { color: var(--color-text); font-family: Consolas, Menlo, Monaco, 'lucida_console', 'Liberation_Mono', 'Courier_New', 'andale_mono', monospaceX, monospace, sans-serif; font-size: .8125rem; }
  .heatmap-cell { position: relative; display: block; width: var(--heatmap-cell-size); height: var(--heatmap-cell-size); }
  .heatmap-tooltip { position: absolute; bottom: calc(100% + .375rem); left: 50%; z-index: 10; display: inline-block; padding: .3rem .5rem; border: 1px solid var(--color-border); background: var(--color-surface); color: var(--color-text); box-shadow: var(--shadow-soft); font-size: .75rem; line-height: 1.2; white-space: nowrap; pointer-events: none; opacity: 0; transform: translate(-50%, .25rem); transition: opacity 160ms ease, transform 160ms ease; }
  .heatmap-cell:hover .heatmap-tooltip { opacity: 1; transform: translate(-50%, 0); }
  .heatmap-tooltip[data-heatmap-portal] { position: fixed; top: 0; left: 0; z-index: 1000; bottom: auto; transform: translateX(-50%); opacity: 0; }
  .heatmap-tooltip[data-heatmap-portal].is-visible { opacity: 1; }
  .heatmap-tooltip-code { font-family: Consolas, Menlo, Monaco, 'lucida_console', 'Liberation_Mono', 'Courier_New', 'andale_mono', monospaceX, monospace, sans-serif; }
  .heatmap-tooltip-label { font-family: var(--reading-font-family); }
  .week-labels span { color: var(--color-muted); font-family: Consolas, Menlo, Monaco, 'lucida_console', 'Liberation_Mono', 'Courier_New', 'andale_mono', monospaceX, monospace, sans-serif; font-size: .625rem; text-align: center; white-space: nowrap; }
  .level-0 { background: var(--heatmap-0); }
  .level-1 { background: var(--heatmap-1); }
  .level-2 { background: var(--heatmap-2); }
  .level-3 { background: var(--heatmap-3); }
  .level-4 { background: var(--heatmap-4); }

  @media (max-width: 37.5rem) {
    .writing-heatmap { display: none; }
  }
</style>