'use strict';

const conf = require('>/conf');

// Pull the first JSON object out of a model response( tolerates ```json fences / prose).
function extractJSON(content){
	let text = String(content).replace(/```json/gi, '').replace(/```/g, '').trim();
	let start = text.indexOf('{');
	let end = text.lastIndexOf('}');
	if(start === -1 || end === -1){
		console.error('extractJSON: no JSON object found in:', content);
		throw new Error('No JSON in model response');
	}
	try{
		return JSON.parse(text.slice(start, end + 1));
	}catch(error){
		console.error('extractJSON: parse failed. extracted:', text.slice(start, end + 1));
		throw error;
	}
}

// One-shot JSON chat against the Ollama cloud model.
async function chatJSON(system, user){
	let res = await fetch(`${conf.ollama.url}/api/chat`, {
		method: 'POST',
		headers: {
			'Content-Type': 'application/json',
			'Authorization': `Bearer ${conf.ollama.apiKey}`,
		},
		body: JSON.stringify({
			model: conf.ollama.model,
			stream: false,
			format: 'json',
			messages: [
				{ role: 'system', content: system },
				{ role: 'user', content: user },
			],
		}),
	});
	if(!res.ok){
		let body = await res.text().catch(() => '');
		console.error(`Ollama chat failed (${res.status}):`, body.slice(0, 500));
		let error = new Error('OllamaError');
		error.message = `Ollama chat failed( ${res.status})`;
		error.status = 502;
		throw error;
	}
	let data = await res.json();
	return extractJSON(data.message && data.message.content);
}

module.exports = { chatJSON, extractJSON };