/**
 * convex/lib/audit.ts
 *
 * Externe Clients und reine Helfer für die Audit-Pipeline. Wird nur aus
 * Convex *Actions* aufgerufen (fetch). Alles dependency-frei (kein "use node"),
 * damit audits.ts Queries/Mutations/Actions in einer Datei halten kann.
 */

// ---- Kosten (Quelle: PitchFast_Pricing_Modell.xlsx) --------------------------

export const AUDIT_COSTS = {
  llmInputPerMTokUsd: 0.75,
  llmOutputPerMTokUsd: 4.5,
  screenshotUsd: 0.0085,
  jinaUsd: 0.003,
};

export function estimateAuditCostUsd(p: {
  inputTokens: number;
  outputTokens: number;
  screenshots: number;
}): number {
  return (
    (p.inputTokens / 1_000_000) * AUDIT_COSTS.llmInputPerMTokUsd +
    (p.outputTokens / 1_000_000) * AUDIT_COSTS.llmOutputPerMTokUsd +
    p.screenshots * AUDIT_COSTS.screenshotUsd +
    AUDIT_COSTS.jinaUsd
  );
}

// ---- ScreenshotOne -----------------------------------------------------------

const SCREENSHOTONE_URL = "https://api.screenshotone.com/take";

/** Einen Screenshot holen (PNG-Bytes). Cookie-Banner/Ads werden gefiltert. */
export async function takeScreenshot(args: {
  accessKey: string;
  url: string;
  device: "desktop" | "mobile";
}): Promise<Uint8Array> {
  const params = new URLSearchParams({
    access_key: args.accessKey,
    url: args.url,
    format: "png",
    full_page: "true",
    block_cookie_banners: "true",
    block_ads: "true",
    block_banners_by_heuristics: "true",
    viewport_width: args.device === "mobile" ? "390" : "1280",
    viewport_height: args.device === "mobile" ? "844" : "900",
    device_scale_factor: args.device === "mobile" ? "2" : "1",
  });
  const res = await fetch(`${SCREENSHOTONE_URL}?${params.toString()}`);
  if (!res.ok) {
    throw new Error(`ScreenshotOne ${res.status}: ${(await res.text()).slice(0, 200)}`);
  }
  return new Uint8Array(await res.arrayBuffer());
}

export function toDataUrl(bytes: Uint8Array): string {
  let bin = "";
  for (const b of bytes) bin += String.fromCharCode(b);
  return `data:image/png;base64,${btoa(bin)}`;
}

// ---- Jina AI Reader (HTML → Markdown) ----------------------------------------

const COMMON_SUBPATHS = ["kontakt", "impressum", "leistungen", "ueber-uns"];
const MARKDOWN_CHAR_CAP = 12000;

/** Startseite + (falls vorhanden) relevante Unterseiten als Markdown. */
export async function fetchSiteMarkdown(args: {
  jinaKey?: string;
  baseUrl: string;
}): Promise<{ markdown: string; pages: string[] }> {
  const headers: Record<string, string> = { "X-Return-Format": "markdown" };
  if (args.jinaKey) headers.Authorization = `Bearer ${args.jinaKey}`;

  const base = args.baseUrl.replace(/\/$/, "");
  const urls = [base, ...COMMON_SUBPATHS.map((p) => `${base}/${p}`)];
  const pages: string[] = [];
  let combined = "";

  for (const u of urls) {
    if (combined.length >= MARKDOWN_CHAR_CAP) break;
    try {
      const res = await fetch(`https://r.jina.ai/${u}`, { headers });
      if (!res.ok) continue;
      const md = await res.text();
      if (md && md.trim().length > 50) {
        pages.push(u);
        combined += `\n\n## Seite: ${u}\n${md}`;
      }
    } catch {
      // Unterseite existiert nicht / Fehler → überspringen
    }
  }
  return { markdown: combined.slice(0, MARKDOWN_CHAR_CAP), pages };
}

// ---- PageSpeed Insights ------------------------------------------------------

export async function fetchPageSpeed(args: {
  googleKey: string;
  url: string;
}): Promise<any> {
  const params = new URLSearchParams({
    url: args.url,
    key: args.googleKey,
    strategy: "mobile",
  });
  params.append("category", "performance");
  params.append("category", "accessibility");
  const res = await fetch(
    `https://www.googleapis.com/pagespeedonline/v5/runPagespeed?${params.toString()}`,
  );
  if (!res.ok) throw new Error(`PageSpeed ${res.status}`);
  const data = await res.json();
  const lh = data.lighthouseResult ?? {};
  const audits = lh.audits ?? {};
  return {
    performanceScore: lh.categories?.performance?.score ?? null,
    accessibilityScore: lh.categories?.accessibility?.score ?? null,
    lcp: audits["largest-contentful-paint"]?.displayValue ?? null,
    cls: audits["cumulative-layout-shift"]?.displayValue ?? null,
    inp: audits["interaction-to-next-paint"]?.displayValue ?? null,
  };
}

// ---- Struktur-Check (regex, dependency-frei) ---------------------------------

export function parseStructuralSignals(html: string, url: string) {
  const m = (re: RegExp) => (html.match(re)?.[1] ?? "").trim();
  return {
    title: m(/<title[^>]*>([^<]*)<\/title>/i) || null,
    metaDescription:
      m(/<meta[^>]+name=["']description["'][^>]+content=["']([^"']*)["']/i) ||
      m(/<meta[^>]+content=["']([^"']*)["'][^>]+name=["']description["']/i) ||
      null,
    h1Count: (html.match(/<h1[\s>]/gi) ?? []).length,
    hasViewport: /<meta[^>]+name=["']viewport["']/i.test(html),
    isHttps: url.startsWith("https://"),
  };
}

// ---- Multimodale Auswertung (OpenRouter, GPT-5.4 mini) -----------------------

const OPENROUTER_URL = "https://openrouter.ai/api/v1/chat/completions";
const MODEL = "openai/gpt-5.4-mini"; // OpenRouter-Slug ggf. verifizieren

export function buildSystemPrompt(skillsRegistry: string): string {
  return [
    "Du bist der Audit-Agent von PitchFast. Du beurteilst die Website eines lokalen",
    "Dienstleisters anhand der folgenden Skill-Registry. Wähle alle zutreffenden",
    "Skills, deren benötigte Eingaben vorliegen, und erzeuge Findings.",
    "",
    "VOICE: Ich-Form, auf Augenhöhe, respektvoll, ohne Floskeln, ohne Dringlichkeit,",
    "ohne Preise. Beobachtung statt Urteil. Übersetze jeden Befund in Kundennutzen.",
    "Severity ist INTERN — niemals im öffentlichen Text nennen, keine Scores/Ampeln.",
    "",
    "Gib AUSSCHLIESSLICH valides JSON zurück, ohne Markdown-Fences, exakt in diesem Schema:",
    `{
  "findings": [{"skill_id": string, "observation": string, "customer_benefit": string,
                "public_phrasing": string, "severity": 1|2|3, "evidence": string}],
  "finalSummary": string,        // intern, vollständig
  "publicAuditText": string,     // extern, voice-konform, wenige konkrete Punkte
  "emailSubject": string,
  "emailBody": string,           // Ich-Form, persönlich, ohne Preise
  "phoneScript": string,
  "ctaType": string,             // z.B. "anruf" | "termin" | "rueckruf"
  "usedSkills": [string]
}`,
    "",
    "=== SKILL-REGISTRY (skills.md) ===",
    skillsRegistry,
  ].join("\n");
}

export async function runMultimodalAnalysis(args: {
  openRouterKey: string;
  systemPrompt: string;
  textContext: string;
  desktopDataUrl: string;
  mobileDataUrl: string;
}): Promise<{ json: any; inputTokens: number; outputTokens: number }> {
  const res = await fetch(OPENROUTER_URL, {
    method: "POST",
    headers: {
      Authorization: `Bearer ${args.openRouterKey}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      model: MODEL,
      response_format: { type: "json_object" },
      messages: [
        { role: "system", content: args.systemPrompt },
        {
          role: "user",
          content: [
            { type: "text", text: args.textContext },
            { type: "image_url", image_url: { url: args.desktopDataUrl } },
            { type: "image_url", image_url: { url: args.mobileDataUrl } },
          ],
        },
      ],
    }),
  });
  if (!res.ok) {
    throw new Error(`OpenRouter ${res.status}: ${(await res.text()).slice(0, 300)}`);
  }
  const data = await res.json();
  const content: string = data.choices?.[0]?.message?.content ?? "{}";
  const clean = content.replace(/```json|```/g, "").trim();
  let json: any;
  try {
    json = JSON.parse(clean);
  } catch {
    throw new Error("LLM-Antwort war kein valides JSON");
  }
  return {
    json,
    inputTokens: data.usage?.prompt_tokens ?? 0,
    outputTokens: data.usage?.completion_tokens ?? 0,
  };
}