backend/services/ollamaClient.js

import { config } from "../config/index.js";
import fs from "node:fs";

async function ollamaFetch(path, body) {
  let res;
  try {
    res = await fetch(`${config.ollama.url}${path}`, {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify(body)
    });
  } catch (err) {
    // #region debug-point C:ollama-fetch-throw
    (() => {
      let u = "http://127.0.0.1:7777/event";
      let s = "chat-502-gateway";
      try {
        const e = fs.readFileSync(".dbg/chat-502-gateway.env", "utf8");
        u = e.match(/DEBUG_SERVER_URL=(.+)/)?.[1] || u;
        s = e.match(/DEBUG_SESSION_ID=(.+)/)?.[1] || s;
      } catch {}
      fetch(u, {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          sessionId: s,
          runId: "post-fix",
          hypothesisId: "C",
          location: "api/services/ollamaClient.js",
          msg: "[DEBUG] ollama fetch threw",
          data: {
            url: config.ollama.url,
            path,
            model: body?.model ?? null,
            promptLen: typeof body?.prompt === "string" ? body.prompt.length : null,
            messagesCount: Array.isArray(body?.messages) ? body.messages.length : null,
            name: err?.name ?? null,
            message: typeof err?.message === "string" ? err.message : null
          },
          ts: Date.now()
        })
      }).catch(() => {});
    })();
    // #endregion
    throw err;
  }

  if (!res.ok) {
    const text = await res.text().catch(() => "");
    // #region debug-point C:ollama-non-200
    (() => {
      let u = "http://127.0.0.1:7777/event";
      let s = "chat-502-gateway";
      try {
        const e = fs.readFileSync(".dbg/chat-502-gateway.env", "utf8");
        u = e.match(/DEBUG_SERVER_URL=(.+)/)?.[1] || u;
        s = e.match(/DEBUG_SESSION_ID=(.+)/)?.[1] || s;
      } catch {}
      fetch(u, {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({
          sessionId: s,
          runId: "post-fix",
          hypothesisId: "C",
          location: "api/services/ollamaClient.js",
          msg: "[DEBUG] ollama non-200",
          data: {
            url: config.ollama.url,
            path,
            status: res.status,
            statusText: res.statusText,
            model: body?.model ?? null,
            promptLen: typeof body?.prompt === "string" ? body.prompt.length : null,
            messagesCount: Array.isArray(body?.messages) ? body.messages.length : null,
            responseSnippet: typeof text === "string" ? text.slice(0, 300) : ""
          },
          ts: Date.now()
        })
      }).catch(() => {});
    })();
    // #endregion
    let msg = `ollama_error:${res.status}:${text || res.statusText}`;
    if (
      res.status === 404 &&
      typeof body?.model === "string" &&
      typeof text === "string" &&
      text.toLowerCase().includes("model") &&
      text.toLowerCase().includes("not found")
    ) {
      let installed = [];
      try {
        const tagsRes = await fetch(`${config.ollama.url}/api/tags`);
        const tags = await tagsRes.json().catch(() => ({}));
        installed = Array.isArray(tags?.models) ? tags.models.map((m) => m?.name).filter(Boolean) : [];
      } catch {}
      const installedList = installed.length ? installed.slice(0, 10).join(",") : "none";
      msg = `ollama_model_not_found:${body.model}:installed=${installedList}:hint=ollama pull ${body.model}`;
    }
    const err = new Error(msg);
    err.statusCode = 502;
    throw err;
  }

  return res.json();
}

export async function embedTexts(texts) {
  const embeddings = [];

  for (const text of texts) {
    const data = await ollamaFetch("/api/embeddings", {
      model: config.ollama.embeddingsModel,
      prompt: text
    });
    embeddings.push(data.embedding);
  }

  return embeddings;
}

export async function chatCompletion({ messages }) {
  const data = await ollamaFetch("/api/chat", {
    model: config.ollama.chatModel,
    messages,
    stream: false
  });

  return {
    content: data?.message?.content ?? ""
  };
}

export async function visionExtractFromImage({ imageBase64, prompt }) {
  const data = await ollamaFetch("/api/chat", {
    model: config.ollama.visionModel,
    messages: [
      {
        role: "user",
        content: prompt,
        images: [imageBase64]
      }
    ],
    stream: false
  });

  return {
    content: data?.message?.content ?? ""
  };
}