video2document/services/modules/llm-chat_gpt/chatgpt.js

const fs = require('fs');
const path = require('path');

const outputDir = path.join(__dirname, "../../../storage/documents"); //  path for output directory

if (!fs.existsSync(outputDir)) {
    fs.mkdirSync(outputDir, { recursive: true }); // Create output directory if it doesn't exist
}

// Ensure SAIA API key is set in environment variables: export SAIA_API_KEY="your_api_key_here"
const SAIA_API_KEY = process.env.SAIA_API_KEY; // Ensure SAIA API key is set in environment variables

const SAIA_URL = "https://chat-ai.academiccloud.de/v1/chat/completions"; //URL for the REST call, used model and action

const module_exports = {
    name: "llm-saia_openai_gpt",
    type: "llm",
    displayname: "SAIA OpenAI GPT OSS 120B",
    description: "Generates documents using OpenAI GPT OSS 120B via SAIA platform",

    async function(parameter) {
        try {
            console.log("SAIA OpenAI GPT module invoked with parameters:", parameter);

            await this.createDocumentFromTranscript( //Call the function to create document with transcript, document type and language
                parameter.inputTranscriptPath, // Path to input transcript file
                parameter.documentTypePath, // Path to document type file which is chosen in the front end by the user
                parameter.language // Language for the document which is chosen in the front end by the user
            );

        } catch (error) {
            console.error("Error in SAIA OpenAI GPT module:", error);
        }
    },

    createDocumentFromTranscript: async function(transcriptPath, documentTypePath, language = "en") { // default language is English
        try {
            const transcript = await fs.promises.readFile(transcriptPath, "utf-8"); //read transcript file from Path
            const documentType = await fs.promises.readFile(documentTypePath, "utf-8"); //read document type from Path
            const promptText = `${documentType}, in language ${language}, transcript:\n\n${transcript}`; //combine doc type, language and transcript - Change prompt here if needed

            // --- REST CALL ---
            const response = await fetch(SAIA_URL, {
                method: "POST",
                headers: {
                    "Authorization": `Bearer ${SAIA_API_KEY}`,
                    "Accept": "application/json",
                    "Content-Type": "application/json"
                },
                body: JSON.stringify({
                    model: "openai-gpt-oss-120b",
                    messages: [
                        { role: "system", content: "You are a helpful assistant that generates documents from transcripts." },
                        { role: "user", content: promptText }
                    ],
                    temperature: 0
                })
            });

            if (!response.ok) { //ok is true when a response was successful
                const text = await response.text();
                throw new Error(`SAIA API error (${response.status}): ${text}`);
            }

            const data = await response.json();

            // Get generated text from response or default to empty string (if null)
            // SAIA uses OpenAI-compatible structure: data.choices[x].message.content
            const output = data.choices?.[0]?.message?.content || "";

            let inputTranscriptName = path.basename(transcriptPath, path.extname(transcriptPath)); // Name for the output file 
            console.log(inputTranscriptName);

            const outPath = path.join(outputDir, `${inputTranscriptName}.md`); // Output file path & name to make naming dynamic. Pulled from input transcript name
            fs.writeFileSync(outPath, output, "utf8"); // Write output to file

            console.log("Generated document written to:", outPath);

        } catch (error) {
            console.error("Error generating SAIA content:", error);
        }
    }
};

module.exports = module_exports;

// CLI Mode: Allow direct execution
if (require.main === module) {
    (async () => {
        const args = process.argv.slice(2);
        
        if (args.length < 2) {
            console.error("Usage: node llm-openai-gpt.js <transcriptPath> <documentTypePath> [language]");
            console.error("Example: node llm-openai-gpt.js ./transcript.json ./docType.json de");
            process.exit(1);
        }

        const [transcriptPath, documentTypePath, language] = args;

        // Check if API key is set
        if (!SAIA_API_KEY) {
            console.error("ERROR: SAIA_API_KEY environment variable is not set!");
            console.error("Please set it with: export SAIA_API_KEY='your_api_key_here'");
            process.exit(1);
        }

        // Check if files exist
        if (!fs.existsSync(transcriptPath)) {
            console.error(`ERROR: Transcript file not found: ${transcriptPath}`);
            process.exit(1);
        }

        if (!fs.existsSync(documentTypePath)) {
            console.error(`ERROR: Document type file not found: ${documentTypePath}`);
            process.exit(1);
        }

        console.log("Starting document generation...");
        console.log(`Transcript: ${transcriptPath}`);
        console.log(`Document Type: ${documentTypePath}`);
        console.log(`Language: ${language || 'en (default)'}`);
        
        await module_exports.createDocumentFromTranscript(
            transcriptPath,
            documentTypePath,
            language || 'en'
        );
        
        console.log("Done!");
    })();
}