import { storage } from './storage';

/**
 * Anthropic API Service
 * Handles communication with the /v1/messages endpoint via Nginx proxy.
 */

const DEFAULT_MODEL = 'claude-sonnet-4-20250514';

export const anthropicApi = {
  async generateContent(systemPrompt, userMessage, maxRetries = 1) {
    // Check if simulation mode is on
    const useSimulation = storage.get('admin:use_simulation') === true;
    if (useSimulation) {
      console.log('[API] Simulation mode active. Mock data will be returned.');
      return await simulateResponse();
    }

    // The API key is now securely injected by the Caddy reverse proxy via environment variables.

    // Model is configurable from Admin > Settings, defaults to the original spec model
    const model = storage.get('admin:model') || DEFAULT_MODEL;
    console.log(`[API] Calling with model: ${model}`);

    let retries = 0;
    while (retries <= maxRetries) {
      try {
        const response = await fetch('/api/anthropic/v1/messages', {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json',
            'anthropic-version': '2023-06-01',
          },
          body: JSON.stringify({
            model: model,
            max_tokens: 8192,
            temperature: 0,
            system: systemPrompt,
            messages: [{ role: 'user', content: userMessage }]
          })
        });

        if (!response.ok) {
          const errData = await response.json().catch(() => ({}));
          console.error('[API] Error response:', errData);
          throw new Error(`API Error: ${response.status} ${response.statusText} - ${JSON.stringify(errData)}`);
        }

        // Detect auth portal session expiry: the portal returns HTML instead of JSON
        const contentType = response.headers.get('content-type') || '';
        if (!contentType.includes('application/json')) {
          throw new Error('Your session has expired. Please refresh the page and log in again.');
        }

        const data = await response.json();
        return data.content[0].text;
      } catch (error) {
        console.error('API call failed:', error);
        retries++;
        if (retries > maxRetries) throw error;
        await new Promise(r => setTimeout(r, 1000));
      }
    }
  }
};

/**
 * Multi-turn chat with optional tool use.
 * Returns the raw Anthropic response so callers can read both `text` and
 * `tool_use` content blocks.
 *
 * @param {string} systemPrompt
 * @param {Array<{role: 'user'|'assistant', content: string}>} messages
 * @param {{tools?: Array}} opts
 * @returns {Promise<{content: Array, stop_reason: string}>}
 */
anthropicApi.chat = async function chat(systemPrompt, messages, opts = {}) {
  const useSimulation = storage.get('admin:use_simulation') === true;
  if (useSimulation) {
    await new Promise(r => setTimeout(r, 600));
    return {
      content: [{
        type: 'text',
        text: 'Simulatiemodus staat aan — vraag een beheerder om Simulation Mode uit te zetten in Admin → Settings om met R42 te chatten.',
      }],
      stop_reason: 'end_turn',
    };
  }

  const model = storage.get('admin:model') || DEFAULT_MODEL;

  const body = {
    model,
    max_tokens: 1024,
    system: systemPrompt,
    messages,
  };
  if (opts.tools && opts.tools.length) body.tools = opts.tools;

  const response = await fetch('/api/anthropic/v1/messages', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'anthropic-version': '2023-06-01',
    },
    body: JSON.stringify(body),
  });

  if (!response.ok) {
    const errData = await response.json().catch(() => ({}));
    throw new Error(`API Error: ${response.status} ${response.statusText} - ${JSON.stringify(errData)}`);
  }

  const contentType = response.headers.get('content-type') || '';
  if (!contentType.includes('application/json')) {
    throw new Error('Your session has expired. Please refresh the page and log in again.');
  }

  return await response.json();
};

async function simulateResponse() {
  await new Promise(r => setTimeout(r, 2000));
  return JSON.stringify({
    topics: [
      { id: "radicale-transparantie", label: "Radicale Transparantie", type: "concept", description: "De kernwaarde van Respellion waarbij alle informatie publiek toegankelijk is." },
      { id: "kennisbeheer", label: "Kennisbeheer", type: "process", description: "Het proces van het vastleggen en ontsluiten van organisatiekennis." },
      { id: "wekelijkse-sessie", label: "Wekelijkse Leersessie", type: "process", description: "Elke week leren medewerkers via AI-gegenereerde vragen en quizzen." }
    ],
    relations: [
      { source: "kennisbeheer", target: "radicale-transparantie", type: "depends_on" },
      { source: "wekelijkse-sessie", target: "kennisbeheer", type: "part_of" }
    ]
  });
}