/**
 * 결재 시스템 API 클라이언트
 * 엔드포인트: /api/approval/*
 */

// API URL 동적 설정
const getApiBaseUrl = (): string => {
  if (process.env.NEXT_PUBLIC_API_URL) {
    return process.env.NEXT_PUBLIC_API_URL;
  }

  if (typeof window !== "undefined") {
    const currentHost = window.location.hostname;

    if (currentHost === "v1.vexplor.com") {
      return "https://api.vexplor.com/api";
    }

    if (currentHost === "localhost" || currentHost === "127.0.0.1") {
      return "http://localhost:8080/api";
    }
  }

  return "/api";
};

const API_BASE = getApiBaseUrl();

function getAuthToken(): string | null {
  if (typeof window === "undefined") return null;
  return localStorage.getItem("authToken") || sessionStorage.getItem("authToken");
}

function getAuthHeaders(): HeadersInit {
  const token = getAuthToken();
  const headers: HeadersInit = { "Content-Type": "application/json" };
  if (token) {
    (headers as Record<string, string>)["Authorization"] = `Bearer ${token}`;
  }
  return headers;
}

// ============================================================
// 공통 타입 정의
// ============================================================

export interface ApiResponse<T = any> {
  success: boolean;
  data?: T;
  message?: string;
  error?: string;
  total?: number;
  page?: number;
  limit?: number;
}

export interface ApprovalDefinition {
  definition_id: number;
  definition_name: string;
  definition_name_eng?: string;
  description?: string;
  default_template_id?: number;
  max_steps: number;
  allow_self_approval: boolean;
  allow_cancel: boolean;
  is_active: string;
  company_code: string;
  created_by?: string;
  created_at: string;
  updated_by?: string;
  updated_at: string;
}

export interface ApprovalLineTemplate {
  template_id: number;
  template_name: string;
  description?: string;
  definition_id?: number;
  definition_name?: string;
  is_active: string;
  company_code: string;
  created_by?: string;
  created_at: string;
  updated_by?: string;
  updated_at: string;
  steps?: ApprovalLineTemplateStep[];
}

export interface ApprovalLineTemplateStep {
  step_id: number;
  template_id: number;
  step_order: number;
  approver_type: "user" | "position" | "dept";
  approver_user_id?: string;
  approver_position?: string;
  approver_dept_code?: string;
  approver_label?: string;
  company_code: string;
}

export interface ApprovalRequest {
  request_id: number;
  title: string;
  description?: string;
  definition_id?: number;
  definition_name?: string;
  target_table: string;
  target_record_id: string;
  target_record_data?: Record<string, any>;
  status: "requested" | "in_progress" | "approved" | "rejected" | "cancelled";
  current_step: number;
  total_steps: number;
  requester_id: string;
  requester_name?: string;
  requester_dept?: string;
  completed_at?: string;
  final_approver_id?: string;
  final_comment?: string;
  screen_id?: number;
  button_component_id?: string;
  company_code: string;
  created_at: string;
  updated_at: string;
  lines?: ApprovalLine[];
}

export interface ApprovalLine {
  line_id: number;
  request_id: number;
  step_order: number;
  approver_id: string;
  approver_name?: string;
  approver_position?: string;
  approver_dept?: string;
  approver_label?: string;
  status: "waiting" | "pending" | "approved" | "rejected" | "skipped";
  comment?: string;
  processed_at?: string;
  company_code: string;
  created_at: string;
  // 요청 정보 (my-pending 조회 시 포함)
  title?: string;
  target_table?: string;
  target_record_id?: string;
  requester_name?: string;
  requester_dept?: string;
  request_created_at?: string;
}

export interface CreateApprovalRequestInput {
  title: string;
  description?: string;
  definition_id?: number;
  target_table: string;
  target_record_id: string;
  target_record_data?: Record<string, any>;
  screen_id?: number;
  button_component_id?: string;
  approvers: {
    approver_id: string;
    approver_name?: string;
    approver_position?: string;
    approver_dept?: string;
    approver_label?: string;
  }[];
}

// ============================================================
// 결재 유형 (Definitions) API
// ============================================================

export async function getApprovalDefinitions(params?: {
  is_active?: string;
  search?: string;
}): Promise<ApiResponse<ApprovalDefinition[]>> {
  try {
    const qs = new URLSearchParams();
    if (params?.is_active) qs.append("is_active", params.is_active);
    if (params?.search) qs.append("search", params.search);

    const response = await fetch(
      `${API_BASE}/approval/definitions${qs.toString() ? `?${qs}` : ""}`,
      { headers: getAuthHeaders(), credentials: "include" }
    );
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function getApprovalDefinition(id: number): Promise<ApiResponse<ApprovalDefinition>> {
  try {
    const response = await fetch(`${API_BASE}/approval/definitions/${id}`, {
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function createApprovalDefinition(data: {
  definition_name: string;
  definition_name_eng?: string;
  description?: string;
  default_template_id?: number;
  max_steps?: number;
  allow_self_approval?: boolean;
  allow_cancel?: boolean;
  is_active?: string;
}): Promise<ApiResponse<ApprovalDefinition>> {
  try {
    const response = await fetch(`${API_BASE}/approval/definitions`, {
      method: "POST",
      headers: getAuthHeaders(),
      credentials: "include",
      body: JSON.stringify(data),
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function updateApprovalDefinition(
  id: number,
  data: Partial<ApprovalDefinition>
): Promise<ApiResponse<ApprovalDefinition>> {
  try {
    const response = await fetch(`${API_BASE}/approval/definitions/${id}`, {
      method: "PUT",
      headers: getAuthHeaders(),
      credentials: "include",
      body: JSON.stringify(data),
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function deleteApprovalDefinition(id: number): Promise<ApiResponse<void>> {
  try {
    const response = await fetch(`${API_BASE}/approval/definitions/${id}`, {
      method: "DELETE",
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

// ============================================================
// 결재선 템플릿 (Templates) API
// ============================================================

export async function getApprovalTemplates(params?: {
  definition_id?: number;
  is_active?: string;
}): Promise<ApiResponse<ApprovalLineTemplate[]>> {
  try {
    const qs = new URLSearchParams();
    if (params?.definition_id) qs.append("definition_id", String(params.definition_id));
    if (params?.is_active) qs.append("is_active", params.is_active);

    const response = await fetch(
      `${API_BASE}/approval/templates${qs.toString() ? `?${qs}` : ""}`,
      { headers: getAuthHeaders(), credentials: "include" }
    );
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function getApprovalTemplate(id: number): Promise<ApiResponse<ApprovalLineTemplate>> {
  try {
    const response = await fetch(`${API_BASE}/approval/templates/${id}`, {
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function createApprovalTemplate(data: {
  template_name: string;
  description?: string;
  definition_id?: number;
  is_active?: string;
  steps?: Omit<ApprovalLineTemplateStep, "step_id" | "template_id" | "company_code">[];
}): Promise<ApiResponse<ApprovalLineTemplate>> {
  try {
    const response = await fetch(`${API_BASE}/approval/templates`, {
      method: "POST",
      headers: getAuthHeaders(),
      credentials: "include",
      body: JSON.stringify(data),
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function updateApprovalTemplate(
  id: number,
  data: {
    template_name?: string;
    description?: string;
    definition_id?: number;
    is_active?: string;
    steps?: Omit<ApprovalLineTemplateStep, "step_id" | "template_id" | "company_code">[];
  }
): Promise<ApiResponse<ApprovalLineTemplate>> {
  try {
    const response = await fetch(`${API_BASE}/approval/templates/${id}`, {
      method: "PUT",
      headers: getAuthHeaders(),
      credentials: "include",
      body: JSON.stringify(data),
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function deleteApprovalTemplate(id: number): Promise<ApiResponse<void>> {
  try {
    const response = await fetch(`${API_BASE}/approval/templates/${id}`, {
      method: "DELETE",
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

// ============================================================
// 결재 요청 (Requests) API
// ============================================================

export async function getApprovalRequests(params?: {
  status?: string;
  target_table?: string;
  requester_id?: string;
  my_approvals?: boolean;
  page?: number;
  limit?: number;
}): Promise<ApiResponse<ApprovalRequest[]>> {
  try {
    const qs = new URLSearchParams();
    if (params?.status) qs.append("status", params.status);
    if (params?.target_table) qs.append("target_table", params.target_table);
    if (params?.requester_id) qs.append("requester_id", params.requester_id);
    if (params?.my_approvals !== undefined) qs.append("my_approvals", String(params.my_approvals));
    if (params?.page) qs.append("page", String(params.page));
    if (params?.limit) qs.append("limit", String(params.limit));

    const response = await fetch(
      `${API_BASE}/approval/requests${qs.toString() ? `?${qs}` : ""}`,
      { headers: getAuthHeaders(), credentials: "include" }
    );
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function getApprovalRequest(id: number): Promise<ApiResponse<ApprovalRequest>> {
  try {
    const response = await fetch(`${API_BASE}/approval/requests/${id}`, {
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function createApprovalRequest(
  data: CreateApprovalRequestInput
): Promise<ApiResponse<ApprovalRequest>> {
  try {
    const response = await fetch(`${API_BASE}/approval/requests`, {
      method: "POST",
      headers: getAuthHeaders(),
      credentials: "include",
      body: JSON.stringify(data),
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function cancelApprovalRequest(id: number): Promise<ApiResponse<void>> {
  try {
    const response = await fetch(`${API_BASE}/approval/requests/${id}/cancel`, {
      method: "POST",
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

// ============================================================
// 결재 라인 처리 (Lines) API
// ============================================================

export async function getMyPendingApprovals(): Promise<ApiResponse<ApprovalLine[]>> {
  try {
    const response = await fetch(`${API_BASE}/approval/my-pending`, {
      headers: getAuthHeaders(),
      credentials: "include",
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}

export async function processApprovalLine(
  lineId: number,
  data: { action: "approved" | "rejected"; comment?: string }
): Promise<ApiResponse<void>> {
  try {
    const response = await fetch(`${API_BASE}/approval/lines/${lineId}/process`, {
      method: "POST",
      headers: getAuthHeaders(),
      credentials: "include",
      body: JSON.stringify(data),
    });
    return await response.json();
  } catch (error: any) {
    return { success: false, error: error.message };
  }
}