/**
 * VikunjaClient - Low-level API wrapper for Vikunja Task Management
 */

/**
 * Helper to ensure the base URL always points to the Vikunja API root (/api/v1)
 * @return {string} Normalized API base URL
 */
function getVikunjaApiBaseUrl_() {
  const config = getVikunjaConfig();
  let baseUrl = config.baseUrl.replace(/\/$/, ''); // Remove trailing slash
  
  if (!baseUrl.endsWith('/api/v1')) {
    baseUrl += '/api/v1';
  }
  
  return baseUrl;
}

function vikunjaRequest_(method, path, payload = null) {
  const apiBaseUrl = getVikunjaApiBaseUrl_();
  const normalizedPath = path.startsWith('/') ? path : '/' + path;
  const url = `${apiBaseUrl}${normalizedPath}`;
  
  console.log(`Vikunja Request: [${method}] ${url}`);
  
  const config = getVikunjaConfig();
  if (!config.token) {
    throw new Error('Vikunja Token is missing from configuration.');
  }

  const options = {
    method: method,
    headers: {
      'Authorization': `Bearer ${config.token}`,
      'Content-Type': 'application/json'
    },
    muteHttpExceptions: true
  };

  console.log('Vikunja Auth Header Present:', !!options.headers.Authorization);

  if (payload) {
    options.payload = JSON.stringify(payload);
  }

  try {
    const response = UrlFetchApp.fetch(url, options);
    const code = response.getResponseCode();
    const rawBody = response.getContentText();
    
    let json = null;
    if (rawBody) {
      try {
        json = JSON.parse(rawBody);
      } catch (e) {
        console.warn(`Non-JSON response received from Vikunja: ${rawBody.substring(0, 200)}...`);
      }
    }

    if (code >= 200 && code < 300) {
      return { 
        ok: true, 
        code: code, 
        data: json, 
        rawBody: rawBody, 
        message: 'Request successful' 
      };
    }
    
    return { 
      ok: false, 
      code: code,
      data: json,
      rawBody: rawBody,
      message: json && json.message ? json.message : `Vikunja API Error ${code}` 
    };
  } catch (e) {
    return { 
      ok: false, 
      code: 500, 
      data: null, 
      rawBody: null, 
      message: `Vikunja Connection Error: ${e.message}` 
    };
  }
}

function getVikunjaTask(taskId) {
  return vikunjaRequest_('GET', `/tasks/${taskId}`);
}

function createVikunjaComment(taskId, commentText) {
  const payload = { comment: commentText };
  const path = `/tasks/${taskId}/comments`;
  
  console.log(`Vikunja Comment Create Attempt: [PUT] ${path} | Payload: ${JSON.stringify(payload)}`);
  
  const res = vikunjaRequest_('PUT', path, payload);
  
  console.log(`Vikunja Comment Response: Code ${res.code} | Body: ${res.rawBody}`);
  return res;
}

function updateVikunjaTask(taskId, data) {
  console.log(`Vikunja Task Update Attempt: [POST] /tasks/${taskId} | Payload: ${JSON.stringify(data)}`);
  const res = vikunjaRequest_('POST', `/tasks/${taskId}`, data);
  console.log(`Vikunja Task Update Response: Code ${res.code} | Body: ${res.rawBody}`);
  return res;
}

function setVikunjaTaskDone(taskId, isDone) {
  return updateVikunjaTask(taskId, { done: isDone });
}

function createVikunjaTask(taskData) {
  const projectId = taskData.projectId || taskData.project_id;
  if (!projectId) {
    return { ok: false, message: 'projectId is required to create a task in Vikunja.' };
  }

    // Construct full payload including priority and description
    const payload = {
      title: taskData.title,
      description: taskData.description || '',
      priority: typeof taskData.priority === 'number' ? taskData.priority : 0
    };
    
    const endpoint = `/projects/${projectId}/tasks`;
    console.log(`Vikunja Create Attempt: [PUT] ${endpoint} | Payload: ${JSON.stringify(payload)}`);
    
    // Using PUT as per instance-specific evidence (POST returns 405)
    const res = vikunjaRequest_('PUT', endpoint, payload);
  
  console.log(`Vikunja Response: Code ${res.code} | Body: ${res.rawBody}`);

  if (res.ok && res.data && res.data.id) {
    return {
      ok: true,
      code: res.code,
      data: res.data,
      rawBody: res.rawBody,
      message: 'Task created successfully'
    };
  }
  
  return { 
    ok: false, 
    code: res.code || 500,
    data: res.data || null,
    rawBody: res.rawBody || '',
    message: `Task creation failed: ${res.message || 'Unknown error'}. Raw body: ${res.rawBody || 'No body'}`
  };
}

function searchVikunjaTasks(query) {
  // API v1 /tasks returns list of tasks. 
  // We fetch and filter client-side to avoid complex filter syntax errors.
  const res = vikunjaRequest_('GET', '/tasks');
  if (!res.ok) return res;
  
  const filtered = (res.data || []).filter(t => 
    t.title && t.title.toLowerCase().includes(query.toLowerCase())
  );
  return { ok: true, data: filtered };
}

function getLabelIdByName_(labelName) {
  const res = vikunjaRequest_('GET', '/labels');
  if (!res.ok) return null;
  
  // Vikunja labels typically use 'title' for the display name
  const label = (res.data || []).find(l => 
    (l.title && l.title.toLowerCase() === labelName.toLowerCase()) || 
    (l.name && l.name.toLowerCase() === labelName.toLowerCase())
  );
  return label ? label.id : null;
}

function createVikunjaLabel(labelName) {
  // Using PUT as per instance evidence for label creation
  const payload = { title: labelName };
  
  console.log(`Vikunja Label Create Attempt: [PUT] /labels | Payload: ${JSON.stringify(payload)}`);
  const res = vikunjaRequest_('PUT', '/labels', payload);
  
  if (res.ok && res.data && res.data.id) {
    return { ok: true, id: res.data.id, code: res.code };
  }
  
  console.error(`Vikunja Label Create Failed: Code ${res.code} | Body: ${res.rawBody}`);
  return { ok: false, message: res.message || 'Failed to create label', code: res.code };
}

function addVikunjaLabel(taskId, labelName) {
  let labelId = getLabelIdByName_(labelName);
  
  // Auto-create label if it doesn't exist
  if (!labelId) {
    const createRes = createVikunjaLabel(labelName);
    if (!createRes.ok) {
      return { 
        ok: false, 
        message: `Label resolution failed: ${createRes.message}`, 
        code: createRes.code 
      };
    }
    labelId = createRes.id;
  }
  
  // Attach label to task using PUT as per instance evidence
  const payload = { label_id: labelId };
  console.log(`Vikunja Label Attach Attempt: [PUT] /tasks/${taskId}/labels | Payload: ${JSON.stringify(payload)}`);
  
  const res = vikunjaRequest_('PUT', `/tasks/${taskId}/labels`, payload);
  
  if (!res.ok) {
    console.error(`Vikunja Label Attach Failed: Code ${res.code} | Body: ${res.rawBody}`);
  }
  
  return res;
}

function deleteVikunjaTask(taskId) {
  return vikunjaRequest_('DELETE', `/tasks/${taskId}`);
}