/**
 * Staff Email API Client
 *
 * Provides API functions for the platform staff email client.
 * This is for platform users (superuser, platform_manager, platform_support)
 * who have been assigned email addresses in staff routing mode.
 */

import apiClient from './client';
import {
  StaffEmailFolder,
  StaffEmail,
  StaffEmailListItem,
  StaffEmailLabel,
  StaffEmailAttachment,
  StaffEmailFilters,
  StaffEmailCreateDraft,
  StaffEmailMove,
  StaffEmailBulkAction,
  StaffEmailReply,
  StaffEmailForward,
  EmailContactSuggestion,
  StaffEmailStats,
} from '../types';

const BASE_URL = '/staff-email';

// ============================================================================
// Folders
// ============================================================================

export const getFolders = async (): Promise<StaffEmailFolder[]> => {
  const response = await apiClient.get(`${BASE_URL}/folders/`);
  return response.data.map(transformFolder);
};

export const createFolder = async (name: string): Promise<StaffEmailFolder> => {
  const response = await apiClient.post(`${BASE_URL}/folders/`, { name });
  return transformFolder(response.data);
};

export const updateFolder = async (id: number, name: string): Promise<StaffEmailFolder> => {
  const response = await apiClient.patch(`${BASE_URL}/folders/${id}/`, { name });
  return transformFolder(response.data);
};

export const deleteFolder = async (id: number): Promise<void> => {
  await apiClient.delete(`${BASE_URL}/folders/${id}/`);
};

// ============================================================================
// Emails (Messages)
// ============================================================================

export interface PaginatedEmailResponse {
  count: number;
  next: string | null;
  previous: string | null;
  results: StaffEmailListItem[];
}

export const getEmails = async (
  filters?: StaffEmailFilters,
  page: number = 1,
  pageSize: number = 50
): Promise<PaginatedEmailResponse> => {
  const params = new URLSearchParams();
  params.append('page', String(page));
  params.append('page_size', String(pageSize));

  if (filters?.folderId) params.append('folder', String(filters.folderId));
  if (filters?.emailAddressId) params.append('email_address', String(filters.emailAddressId));
  if (filters?.isRead !== undefined) params.append('is_read', String(filters.isRead));
  if (filters?.isStarred !== undefined) params.append('is_starred', String(filters.isStarred));
  if (filters?.isImportant !== undefined) params.append('is_important', String(filters.isImportant));
  if (filters?.labelId) params.append('label', String(filters.labelId));
  if (filters?.search) params.append('search', filters.search);
  if (filters?.fromDate) params.append('from_date', filters.fromDate);
  if (filters?.toDate) params.append('to_date', filters.toDate);

  // Debug logging - remove after fixing folder filter issue
  console.log('[StaffEmail API] getEmails called with:', { filters, params: params.toString() });

  const response = await apiClient.get(`${BASE_URL}/messages/?${params.toString()}`);

  // Handle both paginated response {count, results, ...} and legacy array response
  const data = response.data;
  console.log('[StaffEmail API] Raw response data:', data);

  if (Array.isArray(data)) {
    // Legacy format (array of emails)
    console.log('[StaffEmail API] Response (legacy array):', { count: data.length });
    return {
      count: data.length,
      next: null,
      previous: null,
      results: data.map(transformEmailListItem),
    };
  }

  // New paginated format
  const result = {
    count: data.count ?? 0,
    next: data.next ?? null,
    previous: data.previous ?? null,
    results: (data.results ?? []).map(transformEmailListItem),
  };

  // Debug logging - remove after fixing folder filter issue
  console.log('[StaffEmail API] Response:', { count: result.count, resultCount: result.results.length });

  return result;
};

export const getEmail = async (id: number): Promise<StaffEmail> => {
  const response = await apiClient.get(`${BASE_URL}/messages/${id}/`);
  return transformEmail(response.data);
};

export const getEmailThread = async (threadId: string): Promise<StaffEmail[]> => {
  const response = await apiClient.get(`${BASE_URL}/messages/`, {
    params: { thread_id: threadId },
  });
  return response.data.results.map(transformEmail);
};

/**
 * Convert string email addresses to the format expected by the backend.
 * Backend expects: [{ email: "test@example.com", name: "" }]
 * Frontend sends: ["test@example.com"]
 */
function formatEmailAddresses(addresses: string[]): Array<{ email: string; name: string }> {
  return addresses.map((addr) => {
    // Check if it's already in "Name <email>" format
    const match = addr.match(/^(.+?)\s*<(.+?)>$/);
    if (match) {
      return { name: match[1].trim(), email: match[2].trim() };
    }
    return { email: addr.trim(), name: '' };
  });
}

export const createDraft = async (data: StaffEmailCreateDraft): Promise<StaffEmail> => {
  const payload = {
    email_address: data.emailAddressId,
    to_addresses: formatEmailAddresses(data.toAddresses),
    cc_addresses: formatEmailAddresses(data.ccAddresses || []),
    bcc_addresses: formatEmailAddresses(data.bccAddresses || []),
    subject: data.subject,
    body_text: data.bodyText || '',
    body_html: data.bodyHtml || '',
    in_reply_to: data.inReplyTo,
    thread_id: data.threadId,
  };
  const response = await apiClient.post(`${BASE_URL}/messages/`, payload);
  return transformEmail(response.data);
};

export const updateDraft = async (id: number, data: Partial<StaffEmailCreateDraft>): Promise<StaffEmail> => {
  const payload: Record<string, any> = {};
  if (data.toAddresses !== undefined) payload.to_addresses = formatEmailAddresses(data.toAddresses);
  if (data.ccAddresses !== undefined) payload.cc_addresses = formatEmailAddresses(data.ccAddresses);
  if (data.bccAddresses !== undefined) payload.bcc_addresses = formatEmailAddresses(data.bccAddresses);
  if (data.subject !== undefined) payload.subject = data.subject;
  if (data.bodyText !== undefined) payload.body_text = data.bodyText;
  if (data.bodyHtml !== undefined) payload.body_html = data.bodyHtml;

  const response = await apiClient.patch(`${BASE_URL}/messages/${id}/`, payload);
  return transformEmail(response.data);
};

export const deleteDraft = async (id: number): Promise<void> => {
  await apiClient.delete(`${BASE_URL}/messages/${id}/`);
};

export const sendEmail = async (id: number): Promise<StaffEmail> => {
  const response = await apiClient.post(`${BASE_URL}/messages/${id}/send/`);
  return transformEmail(response.data);
};

export const replyToEmail = async (id: number, data: StaffEmailReply): Promise<StaffEmail> => {
  const payload = {
    body_text: data.bodyText || '',
    body_html: data.bodyHtml || '',
    reply_all: data.replyAll || false,
  };
  const response = await apiClient.post(`${BASE_URL}/messages/${id}/reply/`);
  return transformEmail(response.data);
};

export const forwardEmail = async (id: number, data: StaffEmailForward): Promise<StaffEmail> => {
  const payload = {
    to_addresses: formatEmailAddresses(data.toAddresses),
    cc_addresses: formatEmailAddresses(data.ccAddresses || []),
    body_text: data.bodyText || '',
    body_html: data.bodyHtml || '',
  };
  const response = await apiClient.post(`${BASE_URL}/messages/${id}/forward/`, payload);
  return transformEmail(response.data);
};

export const moveEmails = async (data: StaffEmailMove): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/move/`, {
    email_ids: data.emailIds,
    folder_id: data.folderId,
  });
};

export const markAsRead = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/mark_read/`);
};

export const markAsUnread = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/mark_unread/`);
};

export const starEmail = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/star/`);
};

export const unstarEmail = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/unstar/`);
};

export const archiveEmail = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/archive/`);
};

export const trashEmail = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/trash/`);
};

export const restoreEmail = async (id: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${id}/restore/`);
};

export const permanentlyDeleteEmail = async (id: number): Promise<void> => {
  await apiClient.delete(`${BASE_URL}/messages/${id}/`);
};

export const bulkAction = async (data: StaffEmailBulkAction): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/bulk_action/`, {
    email_ids: data.emailIds,
    action: data.action,
  });
};

// ============================================================================
// Labels
// ============================================================================

export const getLabels = async (): Promise<StaffEmailLabel[]> => {
  const response = await apiClient.get(`${BASE_URL}/labels/`);
  return response.data.map(transformLabel);
};

export const createLabel = async (name: string, color: string): Promise<StaffEmailLabel> => {
  const response = await apiClient.post(`${BASE_URL}/labels/`, { name, color });
  return transformLabel(response.data);
};

export const updateLabel = async (id: number, data: { name?: string; color?: string }): Promise<StaffEmailLabel> => {
  const response = await apiClient.patch(`${BASE_URL}/labels/${id}/`, data);
  return transformLabel(response.data);
};

export const deleteLabel = async (id: number): Promise<void> => {
  await apiClient.delete(`${BASE_URL}/labels/${id}/`);
};

export const addLabelToEmail = async (emailId: number, labelId: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${emailId}/add_label/`, { label_id: labelId });
};

export const removeLabelFromEmail = async (emailId: number, labelId: number): Promise<void> => {
  await apiClient.post(`${BASE_URL}/messages/${emailId}/remove_label/`, { label_id: labelId });
};

// ============================================================================
// Contacts
// ============================================================================

export const searchContacts = async (query: string): Promise<EmailContactSuggestion[]> => {
  const response = await apiClient.get(`${BASE_URL}/contacts/`, {
    params: { search: query },
  });
  return response.data.map(transformContact);
};

// ============================================================================
// Attachments
// ============================================================================

export const uploadAttachment = async (file: File, emailId?: number): Promise<StaffEmailAttachment> => {
  const formData = new FormData();
  formData.append('file', file);
  if (emailId) {
    formData.append('email_id', String(emailId));
  }
  const response = await apiClient.post(`${BASE_URL}/attachments/`, formData, {
    headers: { 'Content-Type': 'multipart/form-data' },
  });
  return transformAttachment(response.data);
};

export const deleteAttachment = async (id: number): Promise<void> => {
  await apiClient.delete(`${BASE_URL}/attachments/${id}/`);
};

// ============================================================================
// Sync
// ============================================================================

export const syncEmails = async (): Promise<{ success: boolean; message: string }> => {
  const response = await apiClient.post(`${BASE_URL}/messages/sync/`);
  return response.data;
};

export interface FullSyncTask {
  email_address: string;
  task_id: string;
}

export interface FullSyncResponse {
  status: string;
  tasks: FullSyncTask[];
}

export const fullSyncEmails = async (): Promise<FullSyncResponse> => {
  const response = await apiClient.post(`${BASE_URL}/messages/full_sync/`);
  return response.data;
};

// ============================================================================
// User's Email Addresses
// ============================================================================

export interface UserEmailAddress {
  id: number;
  email_address: string;
  display_name: string;
  color: string;
  is_default: boolean;
  last_check_at: string | null;
  emails_processed_count: number;
}

export const getUserEmailAddresses = async (): Promise<UserEmailAddress[]> => {
  const response = await apiClient.get(`${BASE_URL}/messages/email_addresses/`);
  return response.data;
};

// ============================================================================
// Transform Functions (snake_case -> camelCase)
// ============================================================================

function transformFolder(data: any): StaffEmailFolder {
  return {
    id: data.id,
    owner: data.owner,
    name: data.name,
    folderType: data.folder_type,
    emailCount: data.email_count || 0,
    unreadCount: data.unread_count || 0,
    createdAt: data.created_at,
    updatedAt: data.updated_at,
  };
}

function transformEmailListItem(data: any): StaffEmailListItem {
  return {
    id: data.id,
    folder: data.folder,
    fromAddress: data.from_address,
    fromName: data.from_name || '',
    toAddresses: data.to_addresses || [],
    subject: data.subject || '(No Subject)',
    snippet: data.snippet || '',
    status: data.status,
    isRead: data.is_read,
    isStarred: data.is_starred,
    isImportant: data.is_important,
    hasAttachments: data.has_attachments || false,
    attachmentCount: data.attachment_count || 0,
    threadId: data.thread_id,
    emailDate: data.email_date,
    createdAt: data.created_at,
    labels: (data.labels || []).map(transformLabel),
  };
}

function transformEmail(data: any): StaffEmail {
  return {
    ...transformEmailListItem(data),
    owner: data.owner,
    emailAddress: data.email_address,
    messageId: data.message_id || '',
    inReplyTo: data.in_reply_to,
    references: data.references || '',
    ccAddresses: data.cc_addresses || [],
    bccAddresses: data.bcc_addresses || [],
    bodyText: data.body_text || '',
    bodyHtml: data.body_html || '',
    isAnswered: data.is_answered || false,
    isPermanentlyDeleted: data.is_permanently_deleted || false,
    deletedAt: data.deleted_at,
    attachments: (data.attachments || []).map(transformAttachment),
    updatedAt: data.updated_at,
  };
}

function transformLabel(data: any): StaffEmailLabel {
  return {
    id: data.id,
    owner: data.owner,
    name: data.name,
    color: data.color || '#3b82f6',
    createdAt: data.created_at,
  };
}

function transformAttachment(data: any): StaffEmailAttachment {
  return {
    id: data.id,
    filename: data.filename,
    contentType: data.content_type,
    size: data.size,
    url: data.url || data.file_url || '',
    createdAt: data.created_at,
  };
}

function transformContact(data: any): EmailContactSuggestion {
  return {
    id: data.id,
    owner: data.owner,
    email: data.email,
    name: data.name || '',
    useCount: data.use_count || 0,
    lastUsedAt: data.last_used_at,
  };
}