import { esc, icon, external, section } from "./ui.js";

export function previewHTML(dataset, context) {
  const previews = context.previews[dataset.id] || [];
  if (!previews.length) return "";
  return `<section class="preview" id="dataset-preview" aria-label="${esc(dataset.name)}样例">
    <div class="preview-toolbar">${icon("chevron-left", "上一个样例", "data-prev")}
      <select data-sample aria-label="样例">${previews.map((p, i) => `<option value="${i}">${i + 1} · ${esc(p.caption)}</option>`).join("")}</select>
      ${icon("chevron-right", "下一个样例", "data-next")}
      <select data-mode aria-label="标注类型"></select>
    </div>
    <div class="preview-pair">
      <figure><figcaption data-rgb-label>原始图像</figcaption><svg data-left role="img" aria-label="原始图像" preserveAspectRatio="xMidYMid meet"><image data-rgb/></svg></figure>
      <figure><figcaption><span data-gt-label>来源标注</span><span data-loading role="status" aria-live="polite">加载中</span></figcaption><svg data-right role="img" aria-label="来源标注叠加" preserveAspectRatio="xMidYMid meet"><image data-base/><image data-overlay/></svg></figure>
    </div>
    <div class="preview-adjustments">
      <label>透明度<input data-alpha aria-label="叠加透明度" type="range" min="0" max="100" value="100"><output data-alpha-value>100%</output></label>
      <label>缩放<input data-zoom aria-label="同步缩放" type="range" min="1" max="8" step="0.1" value="1"><output data-zoom-value>1×</output></label>
      <div class="button-group">${icon("scan", "定位手部", "data-hand")}${icon("maximize", "显示全图", "data-reset")}</div>
    </div>
    <div class="preview-thumbs" aria-label="选择样例">${previews.map((p, i) => `<button type="button" data-preview="${i}" aria-label="样例${i + 1}"><img src="${esc(p.rgb)}" alt="" loading="lazy"><span>${i + 1}</span></button>`).join("")}</div>
    <details class="provenance"><summary>来源与抽样</summary><div data-source class="source-content"></div>${samplingHTML(dataset.id, context.sampling)}</details>
  </section>`;
}

export function samplingHTML(id, sampling) {
  const sample = sampling.datasets?.[id];
  if (!sample) return "";
  return `<dl class="facts compact">${Object.entries(sample.categories)
    .map(
      ([dimension, groups]) =>
        `<div><dt>${esc(dimension)}</dt><dd>${Object.entries(groups)
          .map(([name, n]) => `${esc(name)} ${n.selected}/${n.pool}`)
          .join(" · ")}</dd></div>`,
    )
    .join(
      "",
    )}</dl><p class="source-note">${esc(sampling.strategy)} ${esc(sampling.dimensions_note)}</p>`;
}

export function bindPreview(dataset, context) {
  const root = document.getElementById("dataset-preview");
  if (!root) return;
  const previews = context.previews[dataset.id];
  const find = (name) => root.querySelector(`[data-${name}]`);
  let index = 0,
    box,
    version = 0;
  function viewport() {
    const zoom = Number(find("zoom").value);
    const w = box[2] / zoom,
      h = box[3] / zoom;
    const viewBox = [
      box[0] + (box[2] - w) / 2,
      box[1] + (box[3] - h) / 2,
      w,
      h,
    ].join(" ");
    find("left").setAttribute("viewBox", viewBox);
    find("right").setAttribute("viewBox", viewBox);
    find("zoom-value").textContent = `${Number(zoom.toFixed(1))}×`;
  }
  async function annotation() {
    const sample = previews[index],
      mode = sample.modes[Number(find("mode").value)];
    const own = ++version,
      pane = find("right"),
      loading = find("loading");
    find("gt-label").textContent =
      mode.label + (dataset.method === "pseudo" ? " · 预测标注" : "");
    loading.hidden = false;
    loading.textContent = "加载中";
    pane.setAttribute("aria-busy", "true");
    const images = [];
    try {
      await Promise.all(
        [
          ["base", sample.rgb],
          ["overlay", mode.src],
        ].map(
          ([name, url]) =>
            new Promise((resolve, reject) => {
              const image = document.createElementNS(
                "http://www.w3.org/2000/svg",
                "image",
              );
              image.dataset[name] = "";
              image.setAttribute("width", sample.width);
              image.setAttribute("height", sample.height);
              image.style.visibility = "hidden";
              if (name === "overlay")
                image.style.opacity = Number(find("alpha").value) / 100;
              image.onload = resolve;
              image.onerror = reject;
              find(name).replaceWith(image);
              images.push(image);
              image.setAttribute("href", url);
            }),
        ),
      );
      if (own !== version || !root.isConnected) return;
      images.forEach((image) => {
        image.style.visibility = "visible";
      });
      loading.hidden = true;
    } catch (_) {
      if (own !== version || !root.isConnected) return;
      loading.textContent = "图像加载失败";
    } finally {
      if (own === version && root.isConnected)
        pane.setAttribute("aria-busy", "false");
    }
  }
  function show() {
    const sample = previews[index];
    find("sample").value = index;
    for (const [name, value] of [
      ["width", sample.width],
      ["height", sample.height],
      ["href", sample.rgb],
    ])
      find("rgb").setAttribute(name, value);
    find("rgb-label").textContent = sample.rgb_label;
    find("mode").innerHTML = sample.modes
      .map((m, i) => `<option value="${i}">${esc(m.label)}</option>`)
      .join("");
    annotation();
    box = [0, 0, sample.width, sample.height];
    find("zoom").value = 1;
    viewport();
    find("hand").hidden = !sample.crop;
    find("source").innerHTML =
      `<p>${esc(sample.source)}</p>${sample.note ? `<p>${esc(sample.note)}</p>` : ""}<p>${Object.entries(
        sample.strata || {},
      )
        .map(([k, v]) => `${esc(k)}：${esc(v)}`)
        .join(
          " · ",
        )}</p><div class="link-list">${sample.source_page ? external("来源图册", sample.source_page) : ""}${sample.evidence_url ? external("素材记录", sample.evidence_url) : ""}${external("原图", sample.rgb)}</div>${sample.license ? `<p>${esc(sample.license)}</p>` : ""}`;
    root
      .querySelectorAll("[data-preview]")
      .forEach((button) =>
        button.setAttribute(
          "aria-pressed",
          Number(button.dataset.preview) === index,
        ),
      );
  }
  find("prev").onclick = () => {
    index = (index + previews.length - 1) % previews.length;
    show();
  };
  find("next").onclick = () => {
    index = (index + 1) % previews.length;
    show();
  };
  find("sample").onchange = (event) => {
    index = Number(event.target.value);
    show();
  };
  find("mode").onchange = annotation;
  find("alpha").oninput = (event) => {
    find("overlay").style.opacity = event.target.value / 100;
    find("alpha-value").textContent = `${event.target.value}%`;
  };
  find("zoom").oninput = viewport;
  find("hand").onclick = () => {
    box = previews[index].crop;
    find("zoom").value = 1;
    viewport();
  };
  find("reset").onclick = () => {
    box = [0, 0, previews[index].width, previews[index].height];
    find("zoom").value = 1;
    viewport();
  };
  root.querySelectorAll("[data-preview]").forEach((button) => {
    button.onclick = () => {
      index = Number(button.dataset.preview);
      show();
    };
  });
  show();
}

export function figuresHTML(id, context) {
  const entry = context.figures[id];
  if (!entry?.figures?.length) return "";
  return section(
    "采集与标注",
    `${entry.note ? `<p class="source-note">${esc(entry.note)}</p>` : ""}<div class="official-figures">${entry.figures.map((figure) => `<figure><h3>${esc(figure.title)}</h3><div class="figure-images">${figure.images.map((img) => `<a href="${esc(img.src)}" target="_blank" rel="noopener"><img src="${esc(img.src)}" alt="${esc(figure.title)}" width="${img.width}" height="${img.height}" loading="lazy"></a>`).join("")}</div><figcaption>${esc(figure.caption)} ${external(figure.source_label, figure.source_url)}</figcaption><details><summary>原文与署名</summary><p>${esc(figure.original_caption)}</p><p>${esc(figure.attribution)}</p></details></figure>`).join("")}</div>`,
  );
}

export function videoHTML(id, context) {
  const list = context.videos[id] || [];
  if (!list.length) return "";
  return section(
    "动作序列",
    `<select id="clip-select" aria-label="视频序列">${list.map((v, i) => `<option value="${i}">${esc(v.recording_id)} · ${esc(v.source_tag)}</option>`).join("")}</select><video id="clip-player" controls playsinline preload="none"></video><p id="clip-note" class="source-note"></p>`,
  );
}

export function bindVideo(id, context) {
  const select = document.getElementById("clip-select");
  if (!select) return;
  const player = document.getElementById("clip-player");
  const update = () => {
    const video = context.videos[id][Number(select.value)];
    player.pause();
    player.src = video.url;
    document.getElementById("clip-note").textContent =
      `${video.source_tag} · ${video.mano_source} · 来源帧 ${video.source_first_frame}–${video.source_last_frame} · ${video.duration_s}秒`;
  };
  select.onchange = update;
  update();
}