from __future__ import annotations

import html
import json
import shutil
from datetime import datetime
from pathlib import Path
from typing import Any

from .config import SiteSettings

try:
    from markdown_it import MarkdownIt
except ImportError:  # pragma: no cover
    MarkdownIt = None


_MARKDOWN = (
    MarkdownIt("commonmark", {"html": False, "linkify": True}).enable(["table", "strikethrough"])
    if MarkdownIt
    else None
)


def build_site(archive_dir: Path, site_dir: Path, settings: SiteSettings) -> list[dict[str, Any]]:
    archive_dir = Path(archive_dir)
    site_dir = Path(site_dir)
    manifests = _load_run_manifests(archive_dir)

    if site_dir.exists():
        shutil.rmtree(site_dir)
    (site_dir / "assets").mkdir(parents=True, exist_ok=True)
    _write_text(site_dir / "assets" / "style.css", _STYLE_CSS)

    for manifest in manifests:
        run_dir = Path(manifest["_run_dir"])
        _copy_artifacts(site_dir, run_dir, manifest)
        _write_text(
            site_dir / "runs" / manifest["run_id"] / "index.html",
            _render_run_page(manifest, settings),
        )
        for ticker_summary in manifest.get("tickers", []):
            _write_text(
                site_dir / "runs" / manifest["run_id"] / f"{ticker_summary['ticker']}.html",
                _render_ticker_page(manifest, ticker_summary, settings),
            )

    _write_text(site_dir / "index.html", _render_index_page(manifests, settings))
    _write_json(
        site_dir / "feed.json",
        {
            "generated_at": datetime.now().isoformat(),
            "runs": [
                {key: value for key, value in manifest.items() if key != "_run_dir"}
                for manifest in manifests
            ],
        },
    )
    return manifests


def _load_run_manifests(archive_dir: Path) -> list[dict[str, Any]]:
    manifests: list[dict[str, Any]] = []
    runs_root = archive_dir / "runs"
    if not runs_root.exists():
        return manifests

    for path in runs_root.rglob("run.json"):
        payload = json.loads(path.read_text(encoding="utf-8"))
        payload["_run_dir"] = str(path.parent)
        manifests.append(payload)

    manifests.sort(key=lambda item: item.get("started_at", ""), reverse=True)
    return manifests


def _copy_artifacts(site_dir: Path, run_dir: Path, manifest: dict[str, Any]) -> None:
    for ticker_summary in manifest.get("tickers", []):
        download_dir = site_dir / "downloads" / manifest["run_id"] / ticker_summary["ticker"]
        download_dir.mkdir(parents=True, exist_ok=True)
        for relative_path in (ticker_summary.get("artifacts") or {}).values():
            if not relative_path:
                continue
            source = run_dir / relative_path
            if source.is_file():
                shutil.copy2(source, download_dir / source.name)


def _render_index_page(manifests: list[dict[str, Any]], settings: SiteSettings) -> str:
    latest = manifests[0] if manifests else None
    latest_html = (
        f"""
        <section class="hero">
          <div>
            <p class="eyebrow">Latest automated run</p>
            <h1>{_escape(settings.title)}</h1>
            <p class="subtitle">{_escape(settings.subtitle)}</p>
          </div>
          <div class="hero-card">
            <div class="status {latest['status']}">{_escape(latest['status'].replace('_', ' '))}</div>
            <p><strong>Run ID</strong><span>{_escape(latest['run_id'])}</span></p>
            <p><strong>Started</strong><span>{_escape(latest['started_at'])}</span></p>
            <p><strong>Tickers</strong><span>{latest['summary']['total_tickers']}</span></p>
            <p><strong>Success</strong><span>{latest['summary']['successful_tickers']}</span></p>
            <p><strong>Failed</strong><span>{latest['summary']['failed_tickers']}</span></p>
            <a class="button" href="runs/{_escape(latest['run_id'])}/index.html">Open latest run</a>
          </div>
        </section>
        """
        if latest
        else f"""
        <section class="hero">
          <div>
            <p class="eyebrow">Waiting for first run</p>
            <h1>{_escape(settings.title)}</h1>
            <p class="subtitle">{_escape(settings.subtitle)}</p>
          </div>
          <div class="hero-card">
            <div class="status pending">no data yet</div>
            <p>The scheduled workflow has not produced an archived run yet.</p>
          </div>
        </section>
        """
    )

    cards = []
    for manifest in manifests[: settings.max_runs_on_homepage]:
        cards.append(
            f"""
            <article class="run-card">
              <div class="run-card-header">
                <a href="runs/{_escape(manifest['run_id'])}/index.html">{_escape(manifest['run_id'])}</a>
                <span class="status {manifest['status']}">{_escape(manifest['status'].replace('_', ' '))}</span>
              </div>
              <p>{_escape(manifest['started_at'])}</p>
              <p>{manifest['summary']['successful_tickers']} succeeded, {manifest['summary']['failed_tickers']} failed</p>
              <p>{_escape(manifest['settings']['provider'])} / {_escape(manifest['settings']['deep_model'])}</p>
            </article>
            """
        )

    body = latest_html + f"""
    <section class="section">
      <div class="section-head">
        <h2>Recent runs</h2>
        <p>{len(manifests)} archived run(s)</p>
      </div>
      <div class="run-grid">
        {''.join(cards) if cards else '<p class="empty">No archived runs were found.</p>'}
      </div>
    </section>
    """
    return _page_template(settings.title, body, prefix="")


def _render_run_page(manifest: dict[str, Any], settings: SiteSettings) -> str:
    ticker_cards = []
    for ticker_summary in manifest.get("tickers", []):
        ticker_cards.append(
            f"""
            <article class="ticker-card">
              <div class="ticker-card-header">
                <a href="{_escape(ticker_summary['ticker'])}.html">{_escape(ticker_summary['ticker'])}</a>
                <span class="status {ticker_summary['status']}">{_escape(ticker_summary['status'])}</span>
              </div>
              <p><strong>Trade date</strong><span>{_escape(ticker_summary.get('trade_date') or '-')}</span></p>
              <p><strong>Duration</strong><span>{ticker_summary.get('duration_seconds', 0):.1f}s</span></p>
              <p><strong>Decision</strong><span>{_escape(ticker_summary.get('decision') or ticker_summary.get('error') or '-')}</span></p>
            </article>
            """
        )

    body = f"""
    <nav class="breadcrumbs"><a href="../../index.html">Home</a></nav>
    <section class="hero compact">
      <div>
        <p class="eyebrow">Run detail</p>
        <h1>{_escape(manifest['run_id'])}</h1>
        <p class="subtitle">{_escape(manifest['started_at'])}</p>
      </div>
      <div class="hero-card">
        <div class="status {manifest['status']}">{_escape(manifest['status'].replace('_', ' '))}</div>
        <p><strong>Provider</strong><span>{_escape(manifest['settings']['provider'])}</span></p>
        <p><strong>Deep model</strong><span>{_escape(manifest['settings']['deep_model'])}</span></p>
        <p><strong>Quick model</strong><span>{_escape(manifest['settings']['quick_model'])}</span></p>
        <p><strong>Language</strong><span>{_escape(manifest['settings']['output_language'])}</span></p>
      </div>
    </section>
    <section class="section">
      <div class="section-head">
        <h2>Tickers</h2>
        <p>{manifest['summary']['successful_tickers']} success / {manifest['summary']['failed_tickers']} failed</p>
      </div>
      <div class="ticker-grid">
        {''.join(ticker_cards)}
      </div>
    </section>
    """
    return _page_template(f"{manifest['run_id']} | {settings.title}", body, prefix="../../")


def _render_ticker_page(
    manifest: dict[str, Any],
    ticker_summary: dict[str, Any],
    settings: SiteSettings,
) -> str:
    run_dir = Path(manifest["_run_dir"])
    report_html = "<p class='empty'>No report markdown was generated for this ticker.</p>"
    report_relative = (ticker_summary.get("artifacts") or {}).get("report_markdown")
    if report_relative:
        report_path = run_dir / report_relative
        if report_path.exists():
            report_html = _render_markdown(report_path.read_text(encoding="utf-8"))

    download_links = []
    for relative_path in (ticker_summary.get("artifacts") or {}).values():
        if not relative_path:
            continue
        artifact_name = Path(relative_path).name
        download_links.append(
            f"<a class='pill' href='../../downloads/{_escape(manifest['run_id'])}/{_escape(ticker_summary['ticker'])}/{_escape(artifact_name)}'>{_escape(artifact_name)}</a>"
        )

    failure_html = ""
    if ticker_summary["status"] != "success":
        failure_html = (
            "<section class='section'>"
            "<div class='section-head'><h2>Failure</h2></div>"
            f"<pre class='error-block'>{_escape(ticker_summary.get('error') or 'Unknown error')}</pre>"
            "</section>"
        )

    body = f"""
    <nav class="breadcrumbs">
      <a href="../../index.html">Home</a>
      <a href="index.html">{_escape(manifest['run_id'])}</a>
    </nav>
    <section class="hero compact">
      <div>
        <p class="eyebrow">Ticker report</p>
        <h1>{_escape(ticker_summary['ticker'])}</h1>
        <p class="subtitle">{_escape(ticker_summary.get('trade_date') or '-')} / {_escape(ticker_summary['status'])}</p>
      </div>
      <div class="hero-card">
        <div class="status {ticker_summary['status']}">{_escape(ticker_summary['status'])}</div>
        <p><strong>Decision</strong><span>{_escape(ticker_summary.get('decision') or '-')}</span></p>
        <p><strong>Duration</strong><span>{ticker_summary.get('duration_seconds', 0):.1f}s</span></p>
        <p><strong>LLM calls</strong><span>{ticker_summary.get('metrics', {}).get('llm_calls', 0)}</span></p>
        <p><strong>Tool calls</strong><span>{ticker_summary.get('metrics', {}).get('tool_calls', 0)}</span></p>
      </div>
    </section>
    <section class="section">
      <div class="section-head">
        <h2>Artifacts</h2>
      </div>
      <div class="pill-row">
        {''.join(download_links) if download_links else "<span class='empty'>No downloadable artifacts</span>"}
      </div>
    </section>
    {failure_html}
    <section class="section prose">
      <div class="section-head">
        <h2>Rendered report</h2>
      </div>
      {report_html}
    </section>
    """
    return _page_template(
        f"{ticker_summary['ticker']} | {settings.title}",
        body,
        prefix="../../",
    )


def _page_template(title: str, body: str, *, prefix: str) -> str:
    return f"""<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1" />
  <title>{_escape(title)}</title>
  <link rel="stylesheet" href="{prefix}assets/style.css" />
</head>
<body>
  <main class="shell">
    {body}
  </main>
</body>
</html>
"""


def _render_markdown(content: str) -> str:
    if _MARKDOWN is None:
        return f"<pre>{_escape(content)}</pre>"
    return _MARKDOWN.render(content)


def _write_text(path: Path, content: str) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(content, encoding="utf-8")


def _write_json(path: Path, payload: dict[str, Any]) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(payload, indent=2, ensure_ascii=False), encoding="utf-8")


def _escape(value: object) -> str:
    return html.escape(str(value))


_STYLE_CSS = """
:root {
  --bg: #f4efe7;
  --paper: rgba(255, 255, 255, 0.84);
  --ink: #132238;
  --muted: #5d6c7d;
  --line: rgba(19, 34, 56, 0.12);
  --accent: #0f7c82;
  --success: #1f7a4d;
  --warning: #c46a1c;
  --danger: #b23b3b;
  --shadow: 0 18px 45px rgba(17, 34, 51, 0.12);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  font-family: Aptos, "Segoe UI", "Noto Sans KR", sans-serif;
  background:
    radial-gradient(circle at top right, rgba(15, 124, 130, 0.16), transparent 34%),
    radial-gradient(circle at top left, rgba(196, 106, 28, 0.16), transparent 28%),
    linear-gradient(180deg, #f8f3eb 0%, #eef4f5 100%);
}

a { color: inherit; }

.shell {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 24px 0 56px;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.7fr) minmax(280px, 0.9fr);
  gap: 20px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: linear-gradient(135deg, rgba(255,255,255,0.9), rgba(248,251,252,0.9));
  box-shadow: var(--shadow);
}

.hero h1, .section h2 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  letter-spacing: -0.03em;
}

.hero h1 {
  font-size: clamp(2.1rem, 4vw, 3.4rem);
  line-height: 0.95;
}

.subtitle, .section-head p, .hero-card p, .run-card p, .ticker-card p, .breadcrumbs, .empty {
  color: var(--muted);
}

.eyebrow {
  margin: 0 0 14px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.78rem;
  color: var(--accent);
}

.hero-card, .run-card, .ticker-card, .section, .error-block, .prose pre {
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--paper);
  box-shadow: var(--shadow);
}

.hero-card, .run-card, .ticker-card, .section { padding: 18px 20px; }

.hero-card p, .ticker-card p {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin: 10px 0;
}

.status {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: 999px;
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 12px;
}

.status.success { background: rgba(31, 122, 77, 0.12); color: var(--success); }
.status.partial_failure, .status.pending { background: rgba(196, 106, 28, 0.14); color: var(--warning); }
.status.failed { background: rgba(178, 59, 59, 0.12); color: var(--danger); }

.button, .pill {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  border-radius: 999px;
  padding: 10px 16px;
  font-weight: 600;
  border: 1px solid rgba(15, 124, 130, 0.22);
  background: rgba(15, 124, 130, 0.12);
}

.section { margin-top: 20px; }

.section-head, .run-card-header, .ticker-card-header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: baseline;
}

.run-grid, .ticker-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.breadcrumbs {
  display: flex;
  gap: 12px;
  margin: 0 0 12px;
}

.breadcrumbs a::after {
  content: "/";
  margin-left: 12px;
  opacity: 0.4;
}

.breadcrumbs a:last-child::after { display: none; }

.pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.prose { line-height: 1.65; }
.prose h1, .prose h2, .prose h3 { font-family: Georgia, "Times New Roman", serif; }
.prose pre, .error-block {
  padding: 16px;
  overflow: auto;
  white-space: pre-wrap;
  font-family: Consolas, "Courier New", monospace;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
}

.prose th, .prose td {
  border: 1px solid var(--line);
  padding: 10px;
  text-align: left;
}

@media (max-width: 840px) {
  .hero { grid-template-columns: 1fr; }
  .shell { width: min(100% - 20px, 1180px); }
}
"""