GMW/src/moderation/llmModerationClient.ts

import OpenAI from "openai";
import { AbortError } from "p-retry";
import { z } from "zod";
import { config } from "../config.js";
import { createChildLogger } from "../logger.js";
import { retryWithBackoff } from "../retry.js";
import { extractMessageMediaEvidence } from "./messageMetadata.js";
import type {
  AnalysisResult,
  AttachmentRecord,
  MessageRecord,
} from "./types.js";
import { extractUrlsFromText, fetchUrlSafely } from "./urlFetcher.js";

const ModerationResponseSchema = z.object({
  results: z.array(
    z.object({
      message_id: z.union([z.string(), z.number()]).transform(String),
      status: z.enum(["clean", "warn", "flagged"]).catch("clean"),
      flags: z.array(z.string()).catch([]),
      score: z.number().catch(0),
      analysis: z.string().catch(""),
    }),
  ),
});

const log = createChildLogger("llmModerationClient");
const DEFERRAL_ANALYSIS_PATTERN =
  /kurang konteks|kekurangan konteks|perlu (dicek|diperiksa|ditinjau).*(admin|moderator)|admin perlu|moderator perlu|tidak bisa menentukan|tidak dapat menentukan|cannot determine|insufficient context/i;

function hasDeferralAnalysis(analysis: string): boolean {
  return DEFERRAL_ANALYSIS_PATTERN.test(analysis);
}

const openai = new OpenAI({
  apiKey: config.AI_LLM_API_KEY,
  baseURL: config.AI_LLM_BASE_URL,
  maxRetries: 0,
  timeout: 30000,
  fetch: async (url, init) => {
    // Add internal timeout for the global fetch as safety
    const controller = new AbortController();
    const timeout = setTimeout(() => controller.abort(), 30000);

    // Override headers to bypass Cloudflare WAF Bot Fight Mode
    const headers = new Headers(init?.headers);
    headers.set(
      "User-Agent",
      "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36",
    );
    for (const key of Array.from(headers.keys())) {
      if (key.toLowerCase().startsWith("x-stainless")) {
        headers.delete(key);
      }
    }

    const fetchInit = { ...init, headers, signal: controller.signal };

    try {
      const response = await globalThis.fetch(url, fetchInit);
      const body =
        typeof response.text === "function"
          ? await response.text()
          : JSON.stringify(await response.json());

      let normalizedBody = body;
      if (response.ok !== false) {
        try {
          JSON.parse(body);
        } catch (error) {
          log.warn(
            {
              error: error instanceof Error ? error.message : String(error),
              status: response.status ?? 200,
              bodyLength: body.length,
              body,
            },
            "LLM provider returned malformed JSON response body",
          );
          normalizedBody = JSON.stringify(extractJson(body));
        }
      }

      const headers = new Headers(response.headers ?? undefined);
      headers.set("Content-Type", "application/json");
      headers.delete("Content-Length");

      return new Response(normalizedBody, {
        status: response.status ?? 200,
        headers,
      });
    } finally {
      clearTimeout(timeout);
    }
  },
});

/**
 * Helper to extract JSON from a potentially conversational or markdown-wrapped string.
 */
export function extractJson(content: string): any {
  const codeBlockRegex = /```(?:json)?\s*([\s\S]*?)\s*```/g;
  const matches = content.matchAll(codeBlockRegex);
  for (const match of matches) {
    const codeContent = match[1].trim();
    try {
      const parsed = JSON.parse(codeContent);
      if (parsed && typeof parsed === "object") {
        return parsed;
      }
    } catch (_) {}
  }

  for (let start = 0; start < content.length; start++) {
    const firstChar = content[start];
    if (firstChar !== "{" && firstChar !== "[") continue;

    const stack = [firstChar];
    let inString = false;
    let escaped = false;

    for (let i = start + 1; i < content.length; i++) {
      const char = content[i];

      if (inString) {
        if (escaped) {
          escaped = false;
        } else if (char === "\\") {
          escaped = true;
        } else if (char === '"') {
          inString = false;
        }
        continue;
      }

      if (char === '"') {
        inString = true;
        continue;
      }

      if (char === "{" || char === "[") {
        stack.push(char);
        continue;
      }

      const last = stack[stack.length - 1];
      if ((char === "}" && last === "{") || (char === "]" && last === "[")) {
        stack.pop();
        if (stack.length === 0) {
          const candidate = content.slice(start, i + 1);
          try {
            const parsed = JSON.parse(candidate);
            if (parsed && typeof parsed === "object") {
              return parsed;
            }
          } catch (_) {}
          break;
        }
      }
    }
  }

  throw new Error("No JSON object found in response");
}

export function parseModerationResponse(
  content: string,
  targetIds: string[],
): AnalysisResult[] {
  let parsed: any;
  try {
    parsed = JSON.parse(content);
  } catch (e) {
    parsed = extractJson(content);
  }

  if (Array.isArray(parsed)) {
    parsed = { results: parsed };
  } else if (parsed && typeof parsed === "object" && !("results" in parsed)) {
    const arrayKey = Object.keys(parsed).find((key) =>
      Array.isArray((parsed as any)[key]),
    );
    if (arrayKey) {
      parsed.results = (parsed as any)[arrayKey];
    } else {
      parsed = { results: [parsed] };
    }
  }

  const parseResult = ModerationResponseSchema.safeParse(parsed);
  if (!parseResult.success) {
    throw new Error(`Zod validation failed: ${parseResult.error.message}`);
  }

  const response = parseResult.data;
  const foundIds = new Set<string>();
  const targetIdSet = new Set(targetIds);

  const results: (AnalysisResult | null)[] = response.results.map((result) => {
    const { message_id, status, flags, score, analysis } = result;
    const finalId = message_id.trim();

    if (!targetIdSet.has(finalId)) {
      return null;
    }

    if (foundIds.has(finalId)) {
      return null; // Ignore duplicates safely
    }

    foundIds.add(finalId);

    if (hasDeferralAnalysis(analysis)) {
      throw new Error(
        `Deferral analysis is not allowed for message ${finalId}; return a direct moderation decision`,
      );
    }

    return {
      messageId: finalId,
      status: status as "clean" | "warn" | "flagged",
      flags,
      score: Math.max(0, Math.min(1, score)),
      analysis,
    };
  });

  const filteredResults = results.filter(
    (r): r is AnalysisResult => r !== null,
  );

  const missingIds = targetIds.filter((id) => !foundIds.has(id));
  if (missingIds.length > 0) {
    log.warn(
      { missingIds, foundCount: foundIds.size, totalCount: targetIds.length },
      "Some target IDs missing in response - marking as incomplete",
    );
    for (const missingId of missingIds) {
      filteredResults.push({
        messageId: missingId,
        status: "error",
        flags: ["analysis_incomplete"],
        score: 0,
        analysis: "Analysis incomplete - LLM did not process this message",
      });
    }
  }

  return filteredResults;
}

interface ModerationInput {
  targets: MessageRecord[];
  contextText: string;
  attachments?: AttachmentRecord[];
}

interface ModerationOutput {
  results: AnalysisResult[];
  raw: unknown;
}

/**
 * Sniff the first bytes of a buffer to determine if it is a supported image
 * format. Returns the canonical MIME type string on success, or null if the
 * bytes are not a recognizable image.
 *
 * Supported probes (in order):
 *   - JPEG:  FF D8 FF
 *   - PNG:   89 50 4E 47 0D 0A 1A 0A
 *   - GIF:   47 49 46 38 (GIF8)
 *   - WebP:  52 49 46 46 ?? ?? ?? ?? 57 45 42 50 (RIFF....WEBP)
 *   - AVIF / HEIF: 4-byte big-endian size + 66 74 79 70 (ftyp ISO base-media box)
 */
function sniffImageMimeType(buf: Buffer): string | null {
  if (buf.length < 12) return null;

  // JPEG
  if (buf[0] === 0xff && buf[1] === 0xd8 && buf[2] === 0xff) {
    return "image/jpeg";
  }

  // PNG
  if (
    buf[0] === 0x89 &&
    buf[1] === 0x50 &&
    buf[2] === 0x4e &&
    buf[3] === 0x47 &&
    buf[4] === 0x0d &&
    buf[5] === 0x0a &&
    buf[6] === 0x1a &&
    buf[7] === 0x0a
  ) {
    return "image/png";
  }

  // GIF
  if (
    buf[0] === 0x47 &&
    buf[1] === 0x49 &&
    buf[2] === 0x46 &&
    buf[3] === 0x38
  ) {
    return "image/gif";
  }

  // WebP: RIFF????WEBP
  if (
    buf[0] === 0x52 &&
    buf[1] === 0x49 &&
    buf[2] === 0x46 &&
    buf[3] === 0x46 &&
    buf[8] === 0x57 &&
    buf[9] === 0x45 &&
    buf[10] === 0x42 &&
    buf[11] === 0x50
  ) {
    return "image/webp";
  }

  // AVIF / HEIF: ISO base media file format — ftyp box at offset 4
  if (
    buf.length >= 12 &&
    buf[4] === 0x66 &&
    buf[5] === 0x74 &&
    buf[6] === 0x79 &&
    buf[7] === 0x70
  ) {
    const brand = buf.subarray(8, 12).toString("ascii");
    if (brand.startsWith("avif") || brand.startsWith("avis")) {
      return "image/avif";
    }
    if (
      brand.startsWith("mif1") ||
      brand.startsWith("heic") ||
      brand.startsWith("heis")
    ) {
      return "image/heic";
    }
  }

  return null;
}

/**
 * Runs LLM-based moderation analysis on messages.
 * POSTs to AI_LLM_BASE_URL with auth bearer token.
 */
export async function runModerationAnalysis(
  input: ModerationInput,
): Promise<ModerationOutput> {
  const { targets, contextText, attachments } = input;

  if (!targets.length) {
    throw new Error("No targets provided for analysis");
  }

  const targetIds = targets.map((t) => t.id);

  // Build a lookup: message_id → list of resolved base64 image parts
  type MessageImagePart = {
    type: "image_url";
    image_url: { url: string };
    sourceLabel: string;
  };
  type MessageImageMap = Map<string, MessageImagePart[]>;

  // Resolve and download image attachments, grouped by message_id.
  // Only images whose message_id appears in the full attachment list are kept;
  // target messages get priority in the 8-image global cap.
  const getAttachmentImageUrl = (att: AttachmentRecord): string | null =>
    att.uploaded_url ?? null;

  const targetIdSet = new Set(targets.map((t) => t.id));

  const candidateAttachments = (attachments ?? [])
    .filter(
      (att) => getAttachmentImageUrl(att) && att.type.startsWith("image/"),
    )
    .sort((a, b) => {
      // Target-message attachments always come first so they consume the cap first
      const aIsTarget = targetIdSet.has(a.message_id) ? 1 : 0;
      const bIsTarget = targetIdSet.has(b.message_id) ? 1 : 0;
      if (aIsTarget !== bIsTarget) return bIsTarget - aIsTarget;
      // Within the same priority tier, newest first
      return b.created_at - a.created_at;
    })
    .slice(0, 8); // Hard cap — some vision APIs (Nemotron, Omni) reject >8 images

  const messageImageMap: MessageImageMap = new Map();

  await Promise.all(
    candidateAttachments.map(async (att) => {
      const urlToUse = getAttachmentImageUrl(att);
      if (!urlToUse) return;

      const controller = new AbortController();
      const timeoutId = setTimeout(() => controller.abort(), 15000);

      try {
        log.info(
          { attachmentId: att.id, messageId: att.message_id, url: urlToUse },
          "Downloading attachment for base64 encoding",
        );

        const res = await fetch(urlToUse, { signal: controller.signal });
        if (!res.ok) {
          log.warn(
            { attachmentId: att.id, status: res.status, url: urlToUse },
            "Failed to fetch attachment image — non-2xx status",
          );
          return;
        }

        if (!res.body) return;

        let totalBytes = 0;
        const chunks: Uint8Array[] = [];
        const reader = res.body.getReader();

        while (true) {
          const { done, value } = await reader.read();
          if (done) break;

          if (value) {
            totalBytes += value.length;
            if (totalBytes > 10 * 1024 * 1024) {
              log.warn(
                { attachmentId: att.id },
                "Attachment exceeded 10MB limit, aborting stream",
              );
              reader.cancel();
              return;
            }
            chunks.push(value);
          }
        }

        const imageBytes = Buffer.concat(chunks);
        const sniffedMime = sniffImageMimeType(imageBytes);
        if (!sniffedMime) {
          log.warn(
            {
              attachmentId: att.id,
              url: urlToUse,
              dbType: att.type,
              bytesLength: imageBytes.length,
              headerHex: imageBytes.subarray(0, 16).toString("hex"),
            },
            "Skipping attachment: downloaded bytes are not a recognised image format",
          );
          return;
        }

        const dataUrl = `data:${sniffedMime};base64,${imageBytes.toString("base64")}`;
        const part: MessageImagePart = {
          type: "image_url",
          image_url: { url: dataUrl },
          sourceLabel: `[gambar di atas adalah attachment ${att.filename} dari pesan id=${att.message_id}]`,
        };

        const existing = messageImageMap.get(att.message_id) ?? [];
        existing.push(part);
        messageImageMap.set(att.message_id, existing);
      } catch (err) {
        log.warn(
          {
            attachmentId: att.id,
            error: err instanceof Error ? err.message : String(err),
          },
          "Error base64 encoding attachment",
        );
      } finally {
        clearTimeout(timeoutId);
      }
    }),
  );

  // --- Fetch URLs found in target messages ---
  // To avoid slowing down the pipeline too much, we limit to 3 URLs per message.
  const messageWebTextMap = new Map<string, string[]>();

  await Promise.all(
    targets.map(async (msg) => {
      const content = msg.edited_content ?? msg.content;
      const urls = extractUrlsFromText(content).slice(0, 3);
      if (urls.length === 0) return;

      const webTexts: string[] = [];

      await Promise.all(
        urls.map(async (url) => {
          const result = await fetchUrlSafely(url);

          if (result.type === "image" && result.data && result.mimeType) {
            // Append as an image part
            const dataUrl = `data:${result.mimeType};base64,${result.data.toString("base64")}`;
            const part: MessageImagePart = {
              type: "image_url",
              image_url: { url: dataUrl },
              sourceLabel: `[gambar di atas berasal dari link ${url} pada pesan id=${msg.id}]`,
            };
            const existing = messageImageMap.get(msg.id) ?? [];
            existing.push(part);
            messageImageMap.set(msg.id, existing);
          } else if (result.type === "text" && result.textContent) {
            webTexts.push(`[Isi Web dari ${url}]: ${result.textContent}`);
          } else if (result.type === "error") {
            log.debug(
              { url, error: result.error },
              "Failed to fetch URL for moderation context",
            );
          }
        }),
      );

      if (webTexts.length > 0) {
        messageWebTextMap.set(msg.id, webTexts);
      }
    }),
  );

  const mediaImageCandidates = targets.flatMap((msg) => {
    const evidence = extractMessageMediaEvidence(msg.metadata);
    return [
      ...evidence.stickers
        .filter((sticker) => sticker.url)
        .map((sticker) => ({
          messageId: msg.id,
          url: sticker.url,
          label: `[gambar di atas adalah sticker "${sticker.name}" dari pesan id=${msg.id}]`,
        })),
      ...evidence.embeds.flatMap((embed) =>
        [
          embed.image
            ? {
                messageId: msg.id,
                url: embed.image,
                label: `[gambar di atas berasal dari embed image pada pesan id=${msg.id}]`,
              }
            : null,
          embed.thumbnail
            ? {
                messageId: msg.id,
                url: embed.thumbnail,
                label: `[gambar di atas berasal dari embed thumbnail pada pesan id=${msg.id}]`,
              }
            : null,
        ].filter(
          (candidate): candidate is { messageId: string; url: string; label: string } =>
            candidate !== null,
        ),
      ),
    ];
  });

  const remainingImageSlots = Math.max(
    0,
    8 - Array.from(messageImageMap.values()).reduce((sum, imgs) => sum + imgs.length, 0),
  );

  await Promise.all(
    mediaImageCandidates.slice(0, remainingImageSlots).map(async (candidate) => {
      const result = await fetchUrlSafely(candidate.url);
      if (result.type !== "image" || !result.data || !result.mimeType) return;

      const part: MessageImagePart = {
        type: "image_url",
        image_url: {
          url: `data:${result.mimeType};base64,${result.data.toString("base64")}`,
        },
        sourceLabel: candidate.label,
      };
      const existing = messageImageMap.get(candidate.messageId) ?? [];
      existing.push(part);
      messageImageMap.set(candidate.messageId, existing);
    }),
  );

  const analyzeSingleMediaImage = async (
    messageId: string,
    image: MessageImagePart,
  ): Promise<string | null> => {
    try {
      const completion = await openai.chat.completions.create({
        model: config.AI_LLM_MODEL,
        messages: [
          {
            role: "user",
            content: [
              {
                type: "text",
                text: `Analisis media Discord berikut sebagai evidence moderasi. ${image.sourceLabel}\nJelaskan isi visual, teks yang terlihat, konteks risiko, dan apakah ada indikasi spam, scam, SARA, harassment, sexual content, violence, self-harm, doxxing, NSFW, gore, atau illegal content. Jawab Bahasa Indonesia, maksimal 3 kalimat. Jangan bilang kurang konteks atau perlu admin cek; berikan observasi langsung dari media.`,
              },
              { type: "image_url", image_url: image.image_url },
            ],
          },
        ],
        temperature: 0.1,
        top_p: 0.9,
        max_tokens: 500,
        stream: false,
        chat_template_kwargs: { enable_thinking: false },
        reasoning_budget: 0,
      } as OpenAI.Chat.Completions.ChatCompletionCreateParamsNonStreaming);

      const content = completion.choices[0]?.message?.content?.trim();
      if (!content) return null;
      return `[Media analysis for message ${messageId}] ${image.sourceLabel}: ${content}`;
    } catch (error) {
      log.warn(
        {
          messageId,
          error: error instanceof Error ? error.message : String(error),
        },
        "Separate media analysis failed",
      );
      return `[Media analysis for message ${messageId}] ${image.sourceLabel}: gagal dianalisis otomatis; gunakan metadata URL/nama media sebagai evidence.`;
    }
  };

  const messageMediaAnalysisMap = new Map<string, string[]>();
  await Promise.all(
    Array.from(messageImageMap.entries()).flatMap(([messageId, images]) =>
      images.map(async (image) => {
        const summary = await analyzeSingleMediaImage(messageId, image);
        if (!summary) return;
        const existing = messageMediaAnalysisMap.get(messageId) ?? [];
        existing.push(summary);
        messageMediaAnalysisMap.set(messageId, existing);
      }),
    ),
  );


  // -------------------------------------------------------------------------
  // System prompt — Indonesian-first, English as secondary language.
  //
  // Core design decisions:
  //  • Explicitly names the server as a Discord community whose primary
  //    communication language is Indonesian; English is secondary.
  //  • Instructs the model to understand Indonesian slang, abbreviations,
  //    and culturally specific harmful patterns (SARA, hoaks, dll).
  //  • When images are present, instructs the model to treat each image as
  //    an integral part of the message that precedes it — not as standalone
  //    content — so text + image are evaluated together.
  //  • Strict JSON-only output, no markdown or prose.
  // -------------------------------------------------------------------------
  const buildSystemPrompt = (correction?: {
    error: string;
    preview: string;
  }): string => {
    const imageInstructions = `
## Instruksi Analisis Media
Gambar, sticker, embed image, preview link, dan attachment sudah dianalisis lewat request media terpisah sebelum batch utama.
Gunakan baris "Media analysis" sebagai evidence visual utama dalam keputusan moderasi batch ini.
Sticker wajib diperlakukan sebagai image evidence, bukan sekadar nama sticker.
Jangan abaikan link: gunakan isi web, preview image, atau hasil analisis media link bila tersedia.
`;

    const base = `Kamu adalah asisten moderasi konten untuk server Discord berbahasa Indonesia.
Bahasa utama komunitas ini adalah BAHASA INDONESIA. Bahasa Inggris adalah bahasa sekunder.

## Konteks Server
Ini adalah server Discord komunitas Indonesia. Kamu harus memahami:
- Bahasa gaul/slang Indonesia: "anjay", "wkwk", "gws", "gaskeun", "santuy", "njir", "baka", dll.
- Singkatan umum: "gw", "lo", "emg", "kyk", "tdk", "krn", "jgn", dll.
- Konteks budaya lokal: SARA (Suku, Agama, Ras, Antar-golongan), hoaks, ujaran kebencian berbasis konteks Indonesia.
- Perbedaan antara humor/banter biasa vs konten yang benar-benar melanggar.
- Kalimat ambigu dalam bahasa Indonesia harus diberi keputusan final: "clean" bila bukti pelanggaran tidak jelas, "flagged" bila bukti pelanggaran jelas.
- Jangan pernah menulis analisis yang meminta admin/moderator memeriksa ulang, menyebut kurang konteks, atau tidak bisa menentukan. Berikan kesimpulan langsung berdasarkan teks + media + konteks yang tersedia.
- Gambar, sticker, embed, dan preview link adalah evidence utama yang setara dengan teks, bukan sekadar URL teks.
${imageInstructions}
## Konteks Percakapan
${contextText}

## Format Output
Balas HANYA dengan satu objek JSON valid. Tanpa markdown, tanpa prose, tanpa komentar, tanpa XML.
Struktur wajib:
{
  "results": [
    {
      "message_id": "<ID string PERSIS seperti di input>",
      "status": "clean" | "warn" | "flagged",
      "flags": [<string array, kosong jika clean>],
      "score": <float 0.0–1.0>,
      "analysis": "<penjelasan singkat dalam Bahasa Indonesia, maks 2 kalimat>"
    }
  ]
}

Kriteria status:
- "clean": tidak ada pelanggaran yang terdeteksi, atau kasus masih ambigu setelah semua evidence dianalisis
- "warn": risiko ringan yang konkret terdeteksi, misalnya spam borderline atau harassment ringan; BUKAN untuk kurang konteks/perlu admin cek
- "flagged": pelanggaran jelas terdeteksi

Larangan output analysis:
- Jangan tulis "kurang konteks", "perlu dicek admin", "perlu moderator periksa", "tidak bisa menentukan", atau frasa deferral sejenis.
- Jika evidence tidak cukup kuat untuk pelanggaran, status harus "clean" dan analysis menjelaskan alasan langsung.

Flag yang valid: spam, hate_speech, sara, hoaks, harassment, sexual_content, violence, self_harm, doxxing, scam, misinformation, nsfw_image, gore_image, illegal_content

CRITICAL: "message_id" HARUS berupa STRING (dibungkus tanda kutip ganda). Jangan perlakukan ID sebagai angka — ini snowflake Discord yang bisa kehilangan presisi jika diparse sebagai number.`;

    if (correction) {
      return `${base}\n\nRESPON SEBELUMNYA GAGAL VALIDASI.\nError: ${correction.error}\nPreview respons tidak valid:\n${correction.preview}\n\nCoba lagi dengan output JSON yang benar sesuai skema di atas.`;
    }
    return base;
  };

  // -------------------------------------------------------------------------
  // Build the user-turn content.
  // Media images are NOT sent in the main moderation batch. They are analyzed
  // above through separate vision requests, then injected here as text evidence.
  // -------------------------------------------------------------------------

  let lastParseError: string | null = null;
  let lastInvalidContent: string | null = null;

  const buildMessageContent = (): string => {
    const correction = lastParseError
      ? {
          error: lastParseError,
          preview: lastInvalidContent?.slice(0, 800) ?? "<empty>",
        }
      : undefined;

    const systemText = buildSystemPrompt(correction);

    const messagesBlock = targets
      .map((msg) => {
        const content = msg.edited_content ?? msg.content;
        const webTexts = messageWebTextMap.get(msg.id) ?? [];
        const mediaAnalyses = messageMediaAnalysisMap.get(msg.id) ?? [];
        const webContext = webTexts.length > 0 ? `\n${webTexts.join("\n")}` : "";
        const mediaAnalysisContext =
          mediaAnalyses.length > 0 ? `\n${mediaAnalyses.join("\n")}` : "";
        const mediaEvidence = extractMessageMediaEvidence(msg.metadata);
        const mediaContext = [
          mediaEvidence.stickers.length > 0
            ? `[sticker evidence: ${mediaEvidence.stickers.map((s) => `${s.name} (${s.url})`).join(" | ")}]`
            : null,
          mediaEvidence.embeds.length > 0
            ? `[embed evidence: ${mediaEvidence.embeds
                .map((e) => [e.title, e.description, e.url, e.image, e.thumbnail].filter(Boolean).join(" | "))
                .join(" || ")}]`
            : null,
        ]
          .filter(Boolean)
          .join(" ");
        return `[target] id=${msg.id} user=${msg.username}: ${content}${mediaContext ? ` ${mediaContext}` : ""}${webContext}${mediaAnalysisContext}`;
      })
      .join("\n");

    return `${systemText}\n\n## Pesan yang Dianalisis\n${messagesBlock}`;
  };

  let parsed: AnalysisResult[];
  let result: OpenAI.Chat.Completions.ChatCompletion | null = null;
  try {
    const analysis = await retryWithBackoff(
      async () => {
        try {
          const completion = await openai.chat.completions.create({
            model: config.AI_LLM_MODEL,
            messages: [
              {
                role: "user",
                content: buildMessageContent(),
              },
            ],
            temperature: 0.2,
            top_p: 0.95,
            max_tokens: 16384,
            response_format: {
              type: "json_object",
            },
            stream: false,
            chat_template_kwargs: { enable_thinking: false },
            reasoning_budget: 0,
          } as OpenAI.Chat.Completions.ChatCompletionCreateParamsNonStreaming);

          if (
            !completion.choices ||
            !Array.isArray(completion.choices) ||
            !completion.choices[0]
          ) {
            throw new Error("Invalid LLM response structure");
          }

          const content = completion.choices[0].message?.content;
          if (!content) {
            throw new Error("No content in LLM response");
          }

          try {
            return {
              parsed: parseModerationResponse(content, targetIds),
              result: completion,
            };
          } catch (parseError) {
            lastParseError =
              parseError instanceof Error
                ? parseError.message
                : String(parseError);
            lastInvalidContent = content;
            log.warn(
              {
                error: lastParseError,
                contentLength: content.length,
                contentPreview: content.substring(0, 1000),
                fullContent: content,
                targetIds,
                model: config.AI_LLM_MODEL,
              },
              "Failed to parse moderation response from LLM",
            );
            throw parseError;
          }
        } catch (apiError: any) {
          // Immediately abort retries on rate limits or auth errors so the
          // message can return to the DB queue instead of bursting retries.
          if (
            apiError?.status === 429 ||
            apiError?.status === 401 ||
            apiError?.status === 403
          ) {
            throw new AbortError(apiError);
          }
          throw apiError;
        }
      },
      {
        retries: 3,
        minTimeout: 1000,
        maxTimeout: 10000,
        logger: log,
      },
    );
    parsed = analysis.parsed;
    result = analysis.result;
  } catch (parseError) {
    if (!lastInvalidContent) {
      throw parseError;
    }

    const errorMsg =
      parseError instanceof Error ? parseError.message : String(parseError);
    const content: string = lastInvalidContent;

    log.error(
      {
        error: errorMsg,
        contentLength: content.length,
        contentPreview: content.substring(0, 500),
        fullContent: content,
        targetIds,
        model: config.AI_LLM_MODEL,
        timestamp: new Date().toISOString(),
      },
      "Robust Fallback: Failed to parse moderation response. Marking all targets as analysis errors.",
    );
    parsed = targetIds.map((id) => ({
      messageId: id,
      status: "error",
      flags: ["analysis_parse_failed"],
      score: 0,
      analysis: `Parsing failed: ${errorMsg}.`,
    }));
  }

  log.info(
    {
      targetCount: targets.length,
      resultCount: parsed.length,
    },
    "Moderation analysis complete",
  );

  return {
    results: parsed,
    raw: result,
  };
}