// ==========================================
//             API HANDLER FILE
// ==========================================

require('dotenv').config();
const OpenAI = require('openai');
const fs = require('fs');

// Initialize OpenAI client
const openai = new OpenAI({
  apiKey: process.env.OPENAI_UNLIMITED_API_KEY,
});

// ------------------------------------------
// Chat Completions (Text Generation, Reasoning, Function Calling)
// ------------------------------------------

async function createChatCompletion(requestBody, res) {
  if (requestBody.stream) {
    // Handle streaming response
    try {
      const completion = await openai.chat.completions.create({
        ...requestBody,
        stream: true,
      });

      res.setHeader('Content-Type', 'text/event-stream');
      res.setHeader('Cache-Control', 'no-cache');
      res.flushHeaders();

      for await (const part of completion) {
        const data = JSON.stringify(part);
        res.write(`data: ${data}\n\n`);
      }
      res.write('data: [DONE]\n\n');
      res.end();
    } catch (error) {
      console.error('Error in createChatCompletion:', error);
      if (!res.headersSent) {
        res.status(500).json(error.response ? error.response.data : error);
      } else {
        res.write(`data: ${JSON.stringify({ error: error.message })}\n\n`);
        res.end();
      }
    }
  } else {
    // Non-streaming case
    try {
      const completion = await openai.chat.completions.create(requestBody);
      return completion;
    } catch (error) {
      throw error.response ? error.response.data : error;
    }
  }
}

// ------------------------------------------
// Image Generation
// ------------------------------------------

async function createImage(requestBody) {
  try {
    const response = await openai.images.generate(requestBody);
    return response;
  } catch (error) {
    throw error.response ? error.response.data : error;
  }
}

// ------------------------------------------
// Image Editing
// ------------------------------------------

async function createImageEdit(requestBody) {
  try {
    const response = await openai.images.edit({
      image: fs.createReadStream(requestBody.image),
      mask: fs.createReadStream(requestBody.mask),
      prompt: requestBody.prompt,
      n: requestBody.n,
      size: requestBody.size,
    });
    return response;
  } catch (error) {
    throw error.response ? error.response.data : error;
  }
}

// ------------------------------------------
// Image Variation
// ------------------------------------------

async function createImageVariation(requestBody) {
  try {
    const response = await openai.images.createVariation({
      image: fs.createReadStream(requestBody.image),
      n: requestBody.n,
      size: requestBody.size,
    });
    return response;
  } catch (error) {
    throw error.response ? error.response.data : error;
  }
}

// ------------------------------------------
// Audio Transcription
// ------------------------------------------

async function createTranscription(requestBody) {
  try {
    const response = await openai.audio.transcriptions.create({
      file: fs.createReadStream(requestBody.file),
      model: requestBody.model,
    });
    return response;
  } catch (error) {
    throw error.response ? error.response.data : error;
  }
}

// ------------------------------------------
// Text to Speech
// ------------------------------------------

async function createSpeech(requestBody, res) {
  try {
    const response = await openai.audio.speech.create({
      ...requestBody,
    });

    const arrayBuffer = await response.arrayBuffer();
    res.setHeader('Content-Type', 'audio/mpeg');
    res.send(Buffer.from(arrayBuffer));
  } catch (error) {
    console.error('Error in createSpeech:', error);
    if (!res.headersSent) {
      res.status(500).json(error.response ? error.response.data : error);
    }
  }
}

// ------------------------------------------
// Vision (Image Analysis)
// ------------------------------------------

async function createVisionAnalysis(requestBody) {
  try {
    const response = await openai.chat.completions.create(requestBody);
    return response;
  } catch (error) {
    throw error.response ? error.response.data : error;
  }
}

// ------------------------------------------
// Export Modules
// ------------------------------------------

module.exports = {
  createChatCompletion,
  createImage,
  createImageEdit,
  createImageVariation,
  createTranscription,
  createSpeech,
  createVisionAnalysis,
};