// TrueDetect API client.
// Single function: posts a File to /analyze, normalizes errors so the existing
// toast / error states in app.jsx can display them without modification.
//
// API base URL precedence:
//   1. window.TRUEDETECT_API (set on the page if you embed)
//   2. localStorage 'truedetect.apiBase'
//   3. http://localhost:8000  (default)
//
// API key: read from localStorage 'truedetect.apiKey'.

window.TrueDetectAPI = (function(){
  function getBaseUrl(){
    if (window.TRUEDETECT_API) return window.TRUEDETECT_API;
    try {
      const stored = localStorage.getItem('truedetect.apiBase');
      if (stored) return stored;
    } catch(_) {}
    return window.location.origin;
  }

  function getApiKey(){
    try {
      const k = localStorage.getItem('truedetect.apiKey') || '';
      // Strip non-ISO-8859-1 chars so they never land in a fetch header
      return k.replace(/[^\x00-\xff]/g, '');
    }
    catch(_) { return ''; }
  }

  // Map server response to the same error shape app.jsx already handles
  // via the `errorState` tweak: too_large | too_short | invalid_key | server_error.
  function mapError(status, detail){
    if (status === 401) return { kind: 'invalid_key', detail: detail || 'Invalid API key' };
    if (status === 413) return { kind: 'too_large',   detail: detail || 'File too large' };
    if (status === 422) return { kind: 'too_short',   detail: detail || 'Document too short' };
    return { kind: 'server_error', detail: detail || `HTTP ${status}` };
  }

  async function analyzeDocument(file){
    const baseUrl = getBaseUrl().replace(/\/$/, '');
    const apiKey = getApiKey();

    const form = new FormData();
    form.append('file', file, file.name);

    let response;
    try {
      response = await fetch(`${baseUrl}/analyze?include_pdf_report=true`, {
        method: 'POST',
        headers: apiKey ? { 'X-API-Key': apiKey } : {},
        body: form,
      });
    } catch(networkError){
      throw { kind: 'server_error', detail: `Cannot reach engine at ${baseUrl}: ${networkError.message}` };
    }

    if (!response.ok){
      let detail = '';
      try {
        const body = await response.json();
        detail = body.detail || '';
      } catch(_) {}
      throw mapError(response.status, detail);
    }

    return await response.json();
  }

  function setApiKey(key){
    try { localStorage.setItem('truedetect.apiKey', key || ''); } catch(_) {}
  }

  function setApiBase(base){
    try { localStorage.setItem('truedetect.apiBase', base || ''); } catch(_) {}
  }

  return { analyzeDocument, setApiKey, setApiBase, getApiKey, getBaseUrl };
})();