import { serve } from "https://deno.land/std@0.168.0/http/server.ts";
import * as Sentry from "https://deno.land/x/sentry/index.mjs";

Sentry.init({
  dsn: "https://ca41c3f96489cc1b3e69c9a44704f7ee@o4508722276007936.ingest.de.sentry.io/4508772265558096",
  defaultIntegrations: false,
  // Performance Monitoring
  tracesSampleRate: 1.0,
  // Set sampling rate for profiling - this is relative to tracesSampleRate
  profilesSampleRate: 1.0,
});

Sentry.setTag('region', Deno.env.get('SB_REGION'));
Sentry.setTag('execution_id', Deno.env.get('SB_EXECUTION_ID'));

const corsHeaders = {
  'Access-Control-Allow-Origin': '*',
  'Access-Control-Allow-Headers': 'authorization, x-client-info, apikey, content-type',
};

const languagePrompts = {
  en: {
    systemPrompt: "You are helping in a word game. The secret word is",
    task: "Your task is to find a sentence to describe this word without using it directly.",
    instruction: "Answer with a description for this word. Start your answer with",
    noQuotes: "Do not add quotes or backticks. Just answer with the sentence."
  },
  fr: {
    systemPrompt: "Vous aidez dans un jeu de mots. Le mot secret est",
    task: "Votre tâche est de trouver une phrase pour décrire ce mot sans l'utiliser directement.",
    instruction: "Répondez avec une phrase qui commence par",
    noQuotes: "Ne rajoutez pas de guillemets ni de backticks. Répondez simplement par la phrase."
  },
  de: {
    systemPrompt: "Sie helfen bei einem Wortspiel. Das geheime Wort ist",
    task: "Ihre Aufgabe ist es, eine Beschreibung zu finden, der dieses Wort beschreibt, ohne es direkt zu verwenden.",
    instruction: "Beginnen sie ihre Antwort mit",
    noQuotes: "Fügen Sie keine Anführungszeichen oder Backticks hinzu. Antworten Sie einfach mit dem Satz."
  },
  it: {
    systemPrompt: "Stai aiutando in un gioco di parole. La parola segreta è",
    task: "Il tuo compito è trovare una frase per descrivere questa parola senza usarla direttamente.",
    instruction: "Rispondi con una frase completa e grammaticalmente corretta che inizia con",
    noQuotes: "Non aggiungere virgolette o backticks. Rispondi semplicemente con la frase."
  },
  es: {
    systemPrompt: "Estás ayudando en un juego de palabras. La palabra secreta es",
    task: "Tu tarea es encontrar una frase para describir esta palabra sin usarla directamente.",
    instruction: "Responde con una frase completa y gramaticalmente correcta que comience con",
    noQuotes: "No añadas comillas ni backticks. Simplemente responde con la frase."
  },
  pt: {
    systemPrompt: "Você está ajudando em um jogo de palavras. A palavra secreta é",
    task: "Sua tarefa é encontrar uma frase para descrever esta palavra sem usá-la diretamente.",
    instruction: "Responda com uma frase completa e gramaticalmente correta que comece com",
    noQuotes: "Não adicione aspas nem backticks. Simplesmente responda com a frase."
  }
};

const openRouterModels = [
  'google/gemini-2.0-flash-exp:free',
  'mistralai/mistral-nemo'
];

async function generateWord(currentWord: string, existingSentence: string, language: string, model?: string) {
  const openRouterKey = Deno.env.get('OPENROUTER_API_KEY');
  if (!openRouterKey) {
    throw new Error('OpenRouter API key not configured');
  }

  const prompts = languagePrompts[language as keyof typeof languagePrompts] || languagePrompts.en;
  const selectedModel = model || openRouterModels[Math.floor(Math.random() * openRouterModels.length)];

  console.log('Using OpenRouter with model:', selectedModel);

  const response = await fetch("https://openrouter.ai/api/v1/chat/completions", {
    method: "POST",
    headers: {
      "Authorization": `Bearer ${openRouterKey}`,
      "HTTP-Referer": "https://think-in-sync.com",
      "X-Title": "Think in Sync",
      "Content-Type": "application/json"
    },
    body: JSON.stringify({
      model: selectedModel,
      messages: [
        {
          role: "system",
          content: `${prompts.systemPrompt} "${currentWord}". ${prompts.task} ${prompts.instruction} "${existingSentence}". ${prompts.noQuotes}`
        }
      ]
    })
  });

  if (!response.ok) {
    const errorText = await response.text();
    console.error('OpenRouter API error response:', {
      status: response.status,
      statusText: response.statusText,
      body: errorText
    });
    throw new Error(`OpenRouter API error (${response.status}): ${errorText}`);
  }

  const data = await response.json();
  console.log('OpenRouter raw response:', data);

  if (!data?.choices?.[0]?.message?.content) {
    console.error('Invalid OpenRouter API response structure:', data);
    throw new Error('Received invalid response structure from OpenRouter API');
  }

  const aiResponse = data.choices[0].message.content.trim();
  console.log('OpenRouter processed response:', aiResponse);

  const word = aiResponse
    .slice(existingSentence.length)
    .trim()
    .split(' ')[0]
    .replace(/[.,!?]$/, '');

  return { word, model: selectedModel };
}

serve(async (req) => {
  if (req.method === 'OPTIONS') {
    return new Response(null, { headers: corsHeaders });
  }

  try {
    const { currentWord, currentSentence, language = 'en', model } = await req.json();
    console.log('Generating word for:', { currentWord, currentSentence, language, model });

    const existingSentence = currentSentence || '';

    try {
      const { word, model: usedModel } = await generateWord(currentWord, existingSentence, language, model);
      console.log('Successfully generated word:', word, 'using model:', usedModel);
      return new Response(
        JSON.stringify({ word, model: usedModel }),
        { headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
      );
    } catch (error) {
      console.error('OpenRouter API error:', {
        error: error,
        message: error.message,
        stack: error.stack
      });
      Sentry.captureException(error);

      return new Response(
        JSON.stringify({
          error: 'Failed to generate word',
          details: error.message
        }),
        {
          status: 500,
          headers: { ...corsHeaders, 'Content-Type': 'application/json' }
        }
      );
    }
  } catch (error) {
    console.error('Fatal error in generate-word function:', {
      error: error,
      message: error.message,
      stack: error.stack
    });
    Sentry.captureException(error);

    return new Response(
      JSON.stringify({
        error: error.message,
        details: process.env.NODE_ENV === 'development' ? error.stack : undefined
      }),
      {
        status: 500,
        headers: { ...corsHeaders, 'Content-Type': 'application/json' }
      }
    );
  }
});