const API_BASE = process.env.NEXT_PUBLIC_API_URL || "http://localhost:5000";

async function fetchApi<T>(
  path: string,
  options: RequestInit = {}
): Promise<T> {
  const token =
    typeof window !== "undefined" ? localStorage.getItem("helpdesk_token") : null;

  const headers: Record<string, string> = {
    "Content-Type": "application/json",
    ...((options.headers as Record<string, string>) || {}),
  };

  if (token) {
    headers["Authorization"] = `Bearer ${token}`;
  }

  const res = await fetch(`${API_BASE}${path}`, { ...options, headers });

  if (!res.ok) {
    const errorData = await res.json().catch(() => ({}));
    throw new Error(errorData.message || `API Error: ${res.status}`);
  }

  if (res.status === 204) return undefined as T;
  return res.json();
}

// ==================== Auth ====================
export async function login(idUsuario: string, password: string) {
  return fetchApi<{ success: boolean; message?: string; token?: string; user?: HelpDeskUser }>(
    "/api/helpdesk/login",
    { method: "POST", body: JSON.stringify({ idUsuario, password }) }
  );
}

export async function getMe() {
  return fetchApi<HelpDeskUser>("/api/helpdesk/me");
}

// ==================== Tickets ====================
export async function getTickets(params?: {
  status?: string | string[];
  priority?: string;
  assigneeId?: number;
  requesterId?: number;
  groupId?: number;
  search?: string;
  page?: number;
  pageSize?: number;
}) {
  const query = new URLSearchParams();
  if (params) {
    Object.entries(params).forEach(([key, value]) => {
      if (value === undefined || value === "" || value === null) return;
      // El filtro de estados acepta uno o varios: se envía como lista
      // separada por comas (ej: status=Open,Resolved). Vacío = Todos.
      if (Array.isArray(value)) {
        if (value.length === 0) return;
        query.set(key, value.join(","));
        return;
      }
      query.set(key, String(value));
    });
  }
  return fetchApi<TicketListResult>(`/api/helpdesk/tickets?${query.toString()}`);
}

export async function getTicket(id: number) {
  return fetchApi<Ticket>(`/api/helpdesk/ticket/${id}`);
}

export async function createTicket(data: {
  title: string;
  description: string;
  priority?: string;
  assigneeId?: number;
  groupId?: number;
  slaPolicyId?: number;
}) {
  return fetchApi<{ id: number }>("/api/helpdesk/tickets", {
    method: "POST",
    body: JSON.stringify(data),
  });
}

export async function updateTicket(id: number, data: {
  title?: string;
  description?: string;
  priority?: string;
  assigneeId?: number;
  groupId?: number;
}) {
  return fetchApi<void>(`/api/helpdesk/ticket/${id}`, {
    method: "PUT",
    body: JSON.stringify(data),
  });
}

export async function deleteTicket(id: number) {
  return fetchApi<void>(`/api/helpdesk/ticket/${id}`, { method: "DELETE" });
}

export async function updateTicketStatus(id: number, status: string) {
  return fetchApi<void>(`/api/helpdesk/ticket/${id}/status`, {
    method: "PUT",
    body: JSON.stringify({ status }),
  });
}

export async function assignTicket(id: number, assigneeId: number, groupId?: number) {
  return fetchApi<void>(`/api/helpdesk/ticket/${id}/assign`, {
    method: "PUT",
    body: JSON.stringify({ assigneeId, groupId }),
  });
}

export async function getTicketStats() {
  return fetchApi<DashboardStats>("/api/helpdesk/stats");
}

// ==================== Comments ====================
export async function getComments(ticketId: number) {
  return fetchApi<Comment[]>(`/api/helpdesk/comments/${ticketId}`);
}

export async function addComment(
  ticketId: number,
  content: string,
  isInternal: boolean = false
) {
  return fetchApi<{ id: number }>(`/api/helpdesk/comments/${ticketId}`, {
    method: "POST",
    body: JSON.stringify({ content, isInternal }),
  });
}

// ==================== Historial de correos del ticket ====================
// Integración email <-> ticket: enviados desde soporte (mail.log) +
// respuestas recibidas (helpdesk.email_inbound). Visible para quien
// puede ver el ticket (equipo + solicitante).
export interface TicketSentEmail {
  id: number;
  template: string;
  recipient: string;
  subject: string;
  status: string;
  error?: string;
  body?: string;
  createdAt: string;
}

export interface TicketReceivedEmail {
  authorId?: string;
  authorEmail: string;
  subject: string;
  status: string;
  error?: string;
  body?: string;
  commentId?: number;
  createdAt: string;
}

export async function getTicketEmails(ticketId: number) {
  return fetchApi<{ sent: TicketSentEmail[]; received: TicketReceivedEmail[] }>(
    `/api/helpdesk/ticket/${ticketId}/emails`
  );
}

// ==================== Knowledge Base ====================
export async function getKBArticles() {
  return fetchApi<KBArticle[]>("/api/helpdesk/kb/published");
}

export async function searchKB(query: string) {
  return fetchApi<KBArticle[]>(`/api/helpdesk/kb/search?q=${encodeURIComponent(query)}`);
}

export async function getKBCategories() {
  return fetchApi<KBCategory[]>("/api/helpdesk/kb/categories");
}

// ==================== Groups & SLA ====================
export async function getGroups() {
  return fetchApi<Group[]>("/api/helpdesk/groups");
}

export async function getSLAPolicies() {
  return fetchApi<SLAPolicy[]>("/api/helpdesk/sla");
}

// ==================== Types ====================
export interface HelpDeskUser {
  idUsuario: string;
  nombres: string;
  apPaterno: string;
  apMaterno?: string;
  email: string;
  tipo?: string;
  activo: number;
  fono?: string;
  idSede?: number;
  role?: string;
  departmentId?: number;
  departmentName?: string;
}

export interface Ticket {
  id: number;
  title: string;
  description: string;
  status: string;
  priority: string;
  ticketNumber: string;
  requesterId: number;
  requesterName?: string;
  requesterEmail?: string;
  assigneeId?: number;
  assigneeName?: string;
  groupId?: number;
  groupName?: string;
  slaPolicyId?: number;
  createdAt: string;
  updatedAt: string;
  firstResponseAt?: string;
  resolvedAt?: string;
  closedAt?: string;
}

export interface TicketListResult {
  items: Ticket[];
  total: number;
  page: number;
  pageSize: number;
  totalPages: number;
}

export interface Comment {
  id: number;
  ticketId: number;
  userId: string;
  userName?: string;
  content: string;
  isInternal: boolean;
  createdAt: string;
}

export interface Group {
  id: number;
  name: string;
  description?: string;
  isActive: boolean;
  notificationEmail?: string | null;
}

export interface KBArticle {
  id: number;
  title: string;
  content: string;
  categoryId: number;
  categoryName?: string;
  authorId: string;
  authorName?: string;
  isPublished: boolean;
  viewCount: number;
  createdAt: string;
  updatedAt: string;
}

export interface KBCategory {
  id: number;
  name: string;
  description?: string;
  sortOrder: number;
}

export interface SLAPolicy {
  id: number;
  name: string;
  description?: string;
  responseTimeHours: number;
  resolutionTimeHours: number;
  isActive: boolean;
}

export interface DashboardStats {
  totalTickets: number;
  openTickets: number;
  inProgressTickets: number;
  resolvedTickets: number;
  closedTickets: number;
  unassignedTickets: number;
  criticalTickets: number;
  dailyCounts: { date: string; count: number }[];
}

// ==================== Departamentos ====================
export async function createGroup(data: {
  name: string;
  description?: string;
  notificationEmail?: string | null;
}) {
  return fetchApi<Group>("/api/helpdesk/groups", {
    method: "POST",
    body: JSON.stringify(data),
  });
}

export async function updateGroup(
  id: number,
  data: {
    name?: string;
    description?: string;
    isActive?: boolean;
    notificationEmail?: string | null;
  }
) {
  return fetchApi<void>(`/api/helpdesk/groups/${id}`, {
    method: "PUT",
    body: JSON.stringify(data),
  });
}

export async function deleteGroup(id: number) {
  return fetchApi<void>(`/api/helpdesk/groups/${id}`, { method: "DELETE" });
}

// ==================== Equipo ====================
export interface TeamMember extends HelpDeskUser {
  role: string;
  departmentId?: number;
  departmentName?: string;
  isActive?: boolean;
}

export async function getTeam() {
  return fetchApi<TeamMember[]>("/api/helpdesk/users");
}

export async function addMember(data: {
  idUsuario: string;
  role?: string;
  departmentId?: number;
}) {
  return fetchApi<TeamMember>("/api/helpdesk/users", {
    method: "POST",
    body: JSON.stringify(data),
  });
}

export async function updateMember(
  idUsuario: string,
  data: { role?: string; departmentId?: number; isActive?: boolean }
) {
  return fetchApi<TeamMember>(`/api/helpdesk/users/${encodeURIComponent(idUsuario)}`, {
    method: "PUT",
    body: JSON.stringify(data),
  });
}

// ==================== SLA ====================
export async function createSla(data: {
  name: string;
  description?: string;
  responseTimeHours?: number;
  resolutionTimeHours?: number;
}) {
  return fetchApi<SLAPolicy>("/api/helpdesk/sla", {
    method: "POST",
    body: JSON.stringify(data),
  });
}

export async function updateSla(
  id: number,
  data: {
    name?: string;
    description?: string;
    responseTimeHours?: number;
    resolutionTimeHours?: number;
    isActive?: boolean;
  }
) {
  return fetchApi<void>(`/api/helpdesk/sla/${id}`, {
    method: "PUT",
    body: JSON.stringify(data),
  });
}

// ==================== Correo / plantillas (banco único mail.* vía /api/email/*) ====================
export interface EmailTemplate {
  key: string;
  name: string;
  subject: string;
  bodyHtml: string;
  module?: string;
  isActive: boolean;
}

export interface EmailLogEntry {
  id: number;
  template: string;
  module?: string;
  ticketId?: number;
  recipient: string;
  subject: string;
  status: string;
  error?: string;
  createdAt: string;
}

export async function getEmailTemplates() {
  return fetchApi<EmailTemplate[]>("/api/email/templates");
}

export async function createEmailTemplate(data: {
  key: string;
  name: string;
  subject: string;
  bodyHtml: string;
  module?: string;
}) {
  return fetchApi<{ key: string }>("/api/email/templates", {
    method: "POST",
    body: JSON.stringify(data),
  });
}

export async function updateEmailTemplate(
  key: string,
  data: { subject?: string; bodyHtml?: string; isActive?: boolean }
) {
  return fetchApi<void>(`/api/email/templates/${encodeURIComponent(key)}`, {
    method: "PUT",
    body: JSON.stringify(data),
  });
}

export async function getEmailLog(limit = 50, module = "helpdesk") {
  const query = new URLSearchParams({ limit: String(limit) });
  if (module) query.set("module", module);
  return fetchApi<EmailLogEntry[]>(`/api/email/log?${query.toString()}`);
}

// Envío vía route handler propio (/api/correos) → POST /api/email/send con
// X-Module + X-Api-Key en el servidor (la clave nunca va en el bundle).
// Reenvía el Bearer de admin para que el route verifique el rol.
export async function sendModuleEmail(data: {
  to: string | string[];
  templateKey?: string;
  subject?: string;
  htmlBody?: string;
  vars?: Record<string, string | null>;
}) {
  const token =
    typeof window !== "undefined" ? localStorage.getItem("helpdesk_token") : null;
  const res = await fetch("/api/correos", {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      ...(token ? { Authorization: `Bearer ${token}` } : {}),
    },
    body: JSON.stringify(data),
  });
  const payload = await res.json().catch(() => ({}));
  if (!res.ok) {
    throw new Error(
      (payload as { message?: string }).message || `Error de envío: ${res.status}`
    );
  }
  return payload as { success: boolean; sent?: number; failed?: number; message?: string };
}

export async function sendTestEmail(to: string) {
  return sendModuleEmail({
    to,
    subject: "[HelpDesk] Prueba de correo",
    htmlBody: `<p>Prueba de envío desde la Mesa de Ayuda ICHN (${new Date().toISOString().slice(0, 16).replace("T", " ")} UTC).</p><p>Vía banco <code>mail.templates</code> + <code>POST /api/email/send</code> (módulo helpdesk).</p>`,
  });
}

export async function syncInboundEmail() {
  return fetchApi<{
    success: boolean;
    checkedCount: number;
    inserted: number;
    skipped: number;
    error?: string;
  }>("/api/helpdesk/email/inbound/sync", { method: "POST" });
}

// ==================== Notificaciones in-app (estándar multi-módulo) ====================
export interface AppNotification {
  id: number;
  module: string;
  ticketId?: number;
  notifRef?: string;
  type: string;
  title: string;
  body?: string;
  isRead: boolean;
  createdAt: string;
}

export async function getNotifications(limit = 50, module = "", unreadOnly = false) {
  const query = new URLSearchParams({ limit: String(limit) });
  if (module) query.set("module", module);
  if (unreadOnly) query.set("unreadOnly", "true");
  return fetchApi<AppNotification[]>(`/api/notifications?${query.toString()}`);
}

export async function getUnreadCount(module = "") {
  const query = new URLSearchParams();
  if (module) query.set("module", module);
  const qs = query.toString();
  return fetchApi<{ count: number }>(`/api/notifications/unread-count${qs ? `?${qs}` : ""}`);
}

export async function markNotificationRead(id: number) {
  return fetchApi<{ id: number }>(`/api/notifications/${id}/read`, {
    method: "PUT",
  });
}

export async function markAllNotificationsRead(module = "") {
  const query = new URLSearchParams();
  if (module) query.set("module", module);
  const qs = query.toString();
  return fetchApi<{ updated: number }>(`/api/notifications/read-all${qs ? `?${qs}` : ""}`, {
    method: "PUT",
  });
}