import path from "node:path";
import fs from "fs-extra";
import type { CaptureRow, NormalizedConversation } from "./types.js";
import { artifactAssetsDir, artifactDir, artifactIndexPath } from "./artifacts.js";
import { config } from "./config.js";

const fallbackChatGptIconUrl = "https://chatgpt.com/cdn/assets/favicon-l4nq08hd.svg";

function escapeHtml(value: string): string {
  return value
    .replace(/&/g, "&")
    .replace(/</g, "&lt;")
    .replace(/>/g, "&gt;")
    .replace(/"/g, "&quot;");
}

const icons = {
  download: `<svg viewBox="0 0 24 24" aria-hidden="true"><path d="M12 4v10m0 0 4-4m-4 4-4-4"/><path d="M5 18.5h14"/></svg>`,
  image: `<svg viewBox="0 0 24 24" aria-hidden="true"><rect x="4" y="5" width="16" height="14" rx="2"/><path d="m7 16 4-4 3 3 2-2 3 3"/><circle cx="8.5" cy="8.5" r="1.2"/></svg>`,
  share: `<svg viewBox="0 0 24 24" aria-hidden="true"><path d="M8.5 12.5 15.5 8.5M8.5 11.5 15.5 15.5"/><circle cx="6.5" cy="12" r="2.5"/><circle cx="17.5" cy="7.5" r="2.5"/><circle cx="17.5" cy="16.5" r="2.5"/></svg>`,
  chevron: `<svg viewBox="0 0 24 24" aria-hidden="true"><path d="m8 10 4 4 4-4"/></svg>`,
  sun: `<svg viewBox="0 0 24 24" aria-hidden="true"><circle cx="12" cy="12" r="4"/><path d="M12 3v2m0 14v2M3 12h2m14 0h2M5.6 5.6 7 7m10 10 1.4 1.4M18.4 5.6 17 7M7 17l-1.4 1.4"/></svg>`,
  moon: `<svg viewBox="0 0 24 24" aria-hidden="true"><path d="M20 14.6A7.6 7.6 0 0 1 9.4 4 8 8 0 1 0 20 14.6Z"/></svg>`,
  arrowUp: `<svg viewBox="0 0 24 24" aria-hidden="true"><path d="m6 14 6-6 6 6"/><path d="M12 8v12"/></svg>`,
  arrowDown: `<svg viewBox="0 0 24 24" aria-hidden="true"><path d="m6 10 6 6 6-6"/><path d="M12 4v12"/></svg>`
};

function css(): string {
  return `
:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --panel: #ffffff;
  --text: #1f2328;
  --muted: #6b7280;
  --border: #e5e7eb;
  --soft: #f7f7f8;
  --code: #0f172a;
  --code-bg: #f4f4f5;
  --accent: #10a37f;
  --user-bubble: #f4f4f4;
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", "Noto Sans CJK SC", "Noto Sans CJK JP", "Noto Sans CJK KR", "Noto Sans Thai", "Helvetica Neue", Arial, sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #212121;
    --panel: #212121;
    --text: #ececec;
    --muted: #a8a8a8;
    --border: #3f3f46;
    --soft: #2f2f2f;
    --code: #e5e7eb;
    --code-bg: #171717;
    --user-bubble: #303030;
  }
}
html[data-theme="light"] {
  --bg: #ffffff; --panel: #ffffff; --text: #1f2328; --muted: #6b7280; --border: #e5e7eb; --soft: #f7f7f8; --code: #0f172a; --code-bg: #f4f4f5; --user-bubble: #f4f4f4;
}
html[data-theme="dark"] {
  --bg: #212121; --panel: #212121; --text: #ececec; --muted: #a8a8a8; --border: #3f3f46; --soft: #2f2f2f; --code: #e5e7eb; --code-bg: #171717; --user-bubble: #303030;
}
* { box-sizing: border-box; }
body, .topbar, .message.user .content, .content pre, .content :not(pre) > code, .code-block, .code-block .code-header, .content th, .content td, .content blockquote, .content a[data-citation], .downloads, .icon-button, .shot-menu, .shot-menu button, .toast {
  transition: background-color .22s ease, border-color .22s ease, color .22s ease, box-shadow .22s ease;
}
body { margin: 0; background: var(--bg); color: var(--text); font-size: 16px; line-height: 1.65; }
a { color: inherit; }
.page { min-height: 100vh; }
.topbar { position: sticky; top: 0; z-index: 2; border-bottom: 1px solid var(--border); background: color-mix(in srgb, var(--bg) 92%, transparent); backdrop-filter: blur(12px); }
.topbar-inner { max-width: 880px; margin: 0 auto; padding: 14px 20px; display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.topbar-actions { display: inline-flex; align-items: center; gap: 8px; min-width: 0; }
.snapshot-label { font-size: 13px; color: var(--muted); white-space: nowrap; }
.theme-toggle .moon-icon { display: none; }
html[data-theme="dark"] .theme-toggle .sun-icon { display: none; }
html[data-theme="dark"] .theme-toggle .moon-icon { display: block; }
.title { max-width: 880px; margin: 0 auto; padding: 34px 20px 18px; }
h1 { margin: 0; font-size: clamp(28px, 5vw, 44px); line-height: 1.12; letter-spacing: 0; }
.conversation { max-width: 880px; margin: 0 auto; padding: 4px 20px 36px; }
.message { padding: 18px 0; }
.message.assistant { display: block; }
.message.user { display: flex; justify-content: flex-end; }
.message.user .content-wrap { max-width: min(72%, 620px); }
.message.user .content { background: var(--user-bubble); border-radius: 18px; padding: 10px 16px; line-height: 1.55; }
.message.user .content p { margin: 0; }
.avatar { width: 28px; height: 28px; display: grid; place-items: center; margin: 0 0 10px; }
.assistant-icon { width: 28px; height: 28px; display: block; border-radius: 50%; }
.role { display: none; }
.content { min-width: 0; overflow-wrap: anywhere; }
.content h2, .content h3, .content h4 { margin: 1.35em 0 0.55em; line-height: 1.35; font-weight: 700; }
.content h2 { font-size: 1.28em; }
.content h3 { font-size: 1.12em; }
.content h4 { font-size: 1em; }
.content p { margin: 0 0 0.9em; }
.content p:last-child { margin-bottom: 0; }
.content ul, .content ol { margin: 0.6em 0 1em; padding-left: 1.45em; }
.content li { margin: 0.3em 0; padding-left: 0.1em; }
.content li > p { margin: 0.2em 0; }
.content li > ul, .content li > ol { margin: 0.35em 0 0.45em; padding-left: 1.25em; }
.content strong { font-weight: 700; }
.content pre { margin: 1em 0; overflow: auto; padding: 14px 16px; border-radius: 8px; background: var(--code-bg); color: var(--code); font-size: 14px; line-height: 1.55; white-space: pre; overflow-wrap: normal; word-break: normal; }
.content code { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Noto Sans Mono", monospace; }
.content :not(pre) > code { background: var(--code-bg); border-radius: 5px; padding: 0.1em 0.32em; }
.code-block { margin: 1em 0; border-radius: 8px; background: var(--code-bg); overflow: hidden; }
.code-block .code-header { min-height: 34px; display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 6px 10px 6px 14px; color: var(--muted); font-size: 12px; border-bottom: 1px solid var(--border); }
.code-block .code-header span:empty::before { content: "code"; }
.code-block [data-copy-code] { border: 0; background: transparent; color: var(--muted); font: inherit; font-size: 12px; padding: 4px 6px; cursor: pointer; }
.code-block pre { margin: 0; border-radius: 0; background: transparent; }
.content table { width: 100%; border-collapse: collapse; margin: 1em 0; display: block; overflow-x: auto; }
.content th, .content td { border: 1px solid var(--border); padding: 8px 10px; text-align: left; vertical-align: top; }
.content blockquote { border-left: 3px solid var(--border); margin: 1em 0; padding-left: 14px; color: var(--muted); }
.content img { max-width: 100%; height: auto; border-radius: 8px; }
.content a[data-citation] { display: inline-flex; align-items: center; gap: 5px; max-width: min(100%, 260px); min-height: 24px; margin: 0 2px; padding: 2px 8px 2px 5px; border: 1px solid var(--border); border-radius: 999px; background: var(--soft); color: var(--text); font-size: 0.88em; line-height: 1.25; white-space: nowrap; text-decoration: none; vertical-align: -5px; }
.content a[data-citation]:hover { background: color-mix(in srgb, var(--soft) 82%, var(--text) 18%); }
.content a[data-citation] img { width: 16px; height: 16px; max-width: 16px; max-height: 16px; border-radius: 50%; object-fit: cover; flex: 0 0 auto; }
.content a[data-citation] span { overflow: hidden; text-overflow: ellipsis; }
.downloads { position: relative; z-index: 3; border-top: 1px solid var(--border); background: var(--soft); }
.downloads-inner { max-width: 880px; margin: 0 auto; padding: 14px 20px; display: flex; flex-wrap: nowrap; gap: 8px; align-items: center; overflow: visible; }
.icon-button { width: 36px; height: 36px; border: 1px solid var(--border); border-radius: 8px; background: var(--panel); color: var(--text); padding: 0; display: inline-grid; place-items: center; flex: 0 0 auto; cursor: pointer; text-decoration: none; }
.icon-button svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.icon-button:hover { background: color-mix(in srgb, var(--panel) 88%, var(--text) 12%); }
.shot-control { display: inline-flex; align-items: stretch; flex: 0 0 auto; position: relative; }
.shot-control .shot-main { border-radius: 8px 0 0 8px; border-right: 0; }
.shot-control details { position: static; }
.shot-control summary { list-style: none; border-radius: 0 8px 8px 0; width: 28px; }
.shot-control summary::-webkit-details-marker { display: none; }
.shot-control summary svg { width: 15px; height: 15px; }
.shot-menu { position: absolute; left: 0; bottom: calc(100% + 8px); z-index: 20; min-width: 150px; padding: 6px; border: 1px solid var(--border); border-radius: 8px; background: var(--panel); box-shadow: 0 12px 30px rgba(0,0,0,.12); }
.shot-menu button { width: 100%; border: 0; border-radius: 6px; background: transparent; color: var(--text); padding: 8px 10px; font: inherit; font-size: 13px; text-align: left; cursor: pointer; }
.shot-menu button:hover, .shot-menu button[data-current="true"] { background: var(--soft); }
.toast-region { position: fixed; left: 50%; bottom: 22px; z-index: 40; display: grid; justify-items: center; pointer-events: none; transform: translateX(-50%); }
.toast { max-width: min(calc(100vw - 32px), 320px); border: 1px solid var(--border); border-radius: 8px; background: var(--panel); color: var(--text); padding: 9px 12px; font-size: 13px; line-height: 1.35; box-shadow: 0 12px 30px rgba(0,0,0,.14); opacity: 0; transform: translateY(8px); transition: opacity .16s ease, transform .16s ease; }
.toast[data-visible="true"] { opacity: 1; transform: translateY(0); }
.jump-controls { position: fixed; right: 18px; bottom: 18px; z-index: 30; display: grid; gap: 8px; }
.jump-controls .icon-button { box-shadow: 0 8px 24px rgba(0,0,0,.12); }
.source { max-width: 880px; margin: 0 auto; padding: 18px 20px 34px; color: var(--muted); font-size: 12px; }
.source a { color: var(--muted); }
.failure { max-width: 720px; margin: 0 auto; padding: 80px 20px; }
.failure h1 { font-size: 32px; }
@media (max-width: 640px) {
  body { font-size: 15px; }
  .topbar-inner { padding: 12px 16px; }
  .topbar-actions { gap: 6px; }
  .title { padding: 26px 16px 12px; }
  .conversation { padding: 0 16px 28px; }
  .message { padding: 16px 0; }
  .message.assistant { display: block; }
  .message.user .content-wrap { max-width: 84%; }
  .message.user .content { border-radius: 18px; padding: 9px 14px; }
  .avatar, .assistant-icon { width: 26px; height: 26px; }
  .content ul, .content ol { padding-left: 1.25em; }
  .downloads-inner { padding: 12px 16px; }
  .jump-controls { right: 12px; bottom: 12px; }
}`;
}

function initialThemeScript(): string {
  return `!function(){var p=new URLSearchParams(location.search),t=p.get("theme");if(t!=="light"&&t!=="dark")t=matchMedia("(prefers-color-scheme: dark)").matches?"dark":"light";document.documentElement.dataset.theme=t}();`;
}

function pageScript(slug: string): string {
  return `
(function () {
  function currentVariant() {
    var device = matchMedia("(max-width: 640px)").matches ? "mobile" : "desktop";
    var theme = document.documentElement.dataset.theme || (matchMedia("(prefers-color-scheme: dark)").matches ? "dark" : "light");
    return device + "-" + theme;
  }
  function downloadShot(variant) {
    location.href = "screenshots/" + variant + ".png";
  }
  var systemTheme = matchMedia("(prefers-color-scheme: dark)");
  var themeToggle = document.querySelector("[data-theme-toggle]");
  var manualTheme = false;
  function preferredTheme() {
    return systemTheme.matches ? "dark" : "light";
  }
  function applyTheme(theme, manual) {
    document.documentElement.dataset.theme = theme;
    if (manual) manualTheme = true;
    if (themeToggle) {
      themeToggle.setAttribute("aria-label", theme === "dark" ? "Switch to light theme" : "Switch to dark theme");
      themeToggle.setAttribute("title", theme === "dark" ? "Switch to light theme" : "Switch to dark theme");
    }
  }
  var toastTimer;
  function showToast(message) {
    var region = document.querySelector("[data-toast-region]");
    if (!region) return;
    var toast = region.querySelector("[data-toast]");
    if (!toast) {
      toast = document.createElement("div");
      toast.className = "toast";
      toast.dataset.toast = "true";
      region.appendChild(toast);
    }
    toast.textContent = message;
    toast.dataset.visible = "true";
    clearTimeout(toastTimer);
    toastTimer = setTimeout(function () {
      delete toast.dataset.visible;
    }, 1600);
  }
  async function copyText(text, successMessage) {
    try {
      await navigator.clipboard.writeText(text);
      showToast(successMessage);
    } catch (error) {
      showToast("Copy failed");
    }
  }
  var params = new URLSearchParams(location.search);
  var theme = params.get("theme");
  manualTheme = theme === "light" || theme === "dark";
  applyTheme(theme === "light" || theme === "dark" ? theme : preferredTheme(), theme === "light" || theme === "dark");
  systemTheme.addEventListener("change", function () {
    if (!manualTheme) applyTheme(preferredTheme(), false);
  });
  if (themeToggle) themeToggle.addEventListener("click", function () {
    applyTheme(document.documentElement.dataset.theme === "dark" ? "light" : "dark", true);
  });
  var copy = document.querySelector("[data-copy]");
  if (copy) copy.addEventListener("click", async function () {
    await copyText(location.href.replace(/[?#].*$/, ""), "Link copied");
  });
  var jumpTop = document.querySelector("[data-jump-top]");
  if (jumpTop) jumpTop.addEventListener("click", function () {
    scrollTo({ top: 0, behavior: "smooth" });
  });
  var jumpBottom = document.querySelector("[data-jump-bottom]");
  if (jumpBottom) jumpBottom.addEventListener("click", function () {
    scrollTo({ top: document.documentElement.scrollHeight, behavior: "smooth" });
  });
  document.querySelectorAll("[data-copy-code]").forEach(function (button) {
    button.addEventListener("click", async function () {
      var block = button.closest(".code-block");
      var code = block && block.querySelector("code");
      if (!code) return;
      await copyText(code.textContent || "", "Code copied");
    });
  });
  var defaultShot = document.querySelector("[data-shot-current]");
  if (defaultShot) defaultShot.addEventListener("click", function () {
    downloadShot(currentVariant());
  });
  document.querySelectorAll("[data-shot-variant]").forEach(function (button) {
    if (button.dataset.shotVariant === currentVariant()) button.dataset.current = "true";
    button.addEventListener("click", function () {
      downloadShot(button.dataset.shotVariant);
    });
  });
})();`;
}

function messageAvatar(role: string, chatGptIconSrc?: string): string {
  if (role === "assistant") {
    return `<div class="avatar"><img class="assistant-icon" src="${escapeHtml(chatGptIconSrc || fallbackChatGptIconUrl)}" alt="ChatGPT"></div>`;
  }
  return "";
}

export function renderConversationPage(slug: string, conversation: NormalizedConversation): string {
  const title = escapeHtml(conversation.title);
  const messages = conversation.messages
    .map((message) => `
      <article class="message ${message.role}">
        ${messageAvatar(message.role, conversation.chatGptIconSrc)}
        <div class="content-wrap">
          <div class="role">${message.role === "assistant" ? "Assistant" : message.role === "user" ? "You" : "Message"}</div>
          <div class="content">${message.html}</div>
        </div>
      </article>`)
    .join("\n");

  return `<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <meta name="robots" content="noindex">
  <title>${title}</title>
  <script>${initialThemeScript()}</script>
  <style>${css()}</style>
</head>
<body>
  <div class="page">
    <header class="topbar"><div class="topbar-inner"><strong>AI Share</strong><div class="topbar-actions"><span class="snapshot-label">ChatGPT snapshot</span><button class="icon-button theme-toggle" type="button" data-theme-toggle aria-label="Switch theme" title="Switch theme"><span class="sun-icon">${icons.sun}</span><span class="moon-icon">${icons.moon}</span></button></div></div></header>
    <main>
      <section class="title"><h1>${title}</h1></section>
      <section class="conversation">${messages}</section>
    </main>
    <section class="downloads">
      <div class="downloads-inner">
        <a class="icon-button" href="download" aria-label="Download export" title="Download export">${icons.download}</a>
        <div class="shot-control">
          <button class="icon-button shot-main" type="button" data-shot-current aria-label="Download screenshot" title="Download screenshot">${icons.image}</button>
          <details>
            <summary class="icon-button" aria-label="Choose screenshot variant" title="Choose screenshot variant">${icons.chevron}</summary>
            <div class="shot-menu">
              <button type="button" data-shot-variant="desktop-light">Desktop light</button>
              <button type="button" data-shot-variant="desktop-dark">Desktop dark</button>
              <button type="button" data-shot-variant="mobile-light">Mobile light</button>
              <button type="button" data-shot-variant="mobile-dark">Mobile dark</button>
            </div>
          </details>
        </div>
        <button class="icon-button" type="button" data-copy aria-label="Copy link" title="Copy link">${icons.share}</button>
      </div>
    </section>
    <footer class="source">
      Captured from ChatGPT on ${escapeHtml(new Date(conversation.capturedAt).toLocaleString())}.
      Source: <a href="${escapeHtml(conversation.sourceUrl)}" rel="nofollow noreferrer">${escapeHtml(conversation.sourceUrl)}</a>
    </footer>
    <div class="jump-controls" aria-label="Page navigation">
      <button class="icon-button" type="button" data-jump-top aria-label="Jump to top" title="Jump to top">${icons.arrowUp}</button>
      <button class="icon-button" type="button" data-jump-bottom aria-label="Jump to bottom" title="Jump to bottom">${icons.arrowDown}</button>
    </div>
    <div class="toast-region" data-toast-region aria-live="polite" aria-atomic="true"></div>
  </div>
  <script>${pageScript(slug)}</script>
</body>
</html>`;
}

export function renderFailurePage(row: CaptureRow): string {
  const title = escapeHtml(row.title || "Capture failed");
  const reason = escapeHtml(row.error_public || "This ChatGPT share could not be captured.");
  return `<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <meta name="robots" content="noindex">
  <title>${title}</title>
  <style>${css()}</style>
</head>
<body>
  <main class="failure">
    <p class="snapshot-label">AI Share capture</p>
    <h1>${title}</h1>
    <p>${reason}</p>
  </main>
  <footer class="source">
    Source: <a href="${escapeHtml(row.source_url)}" rel="nofollow noreferrer">${escapeHtml(row.source_url)}</a>
  </footer>
</body>
</html>`;
}

export async function writeConversationArtifact(slug: string, conversation: NormalizedConversation): Promise<void> {
  await fs.ensureDir(artifactAssetsDir(slug));
  await fs.writeFile(artifactIndexPath(slug), renderConversationPage(slug, conversation), "utf8");
}

export async function writeFailureArtifact(row: CaptureRow): Promise<void> {
  if (!row.slug) return;
  await fs.ensureDir(artifactDir(row.slug));
  await fs.writeFile(path.join(artifactDir(row.slug), "index.html"), renderFailurePage(row), "utf8");
}