import { apiRequestData } from "./http";

export type SalaryItemType = "earning" | "deduction";
export type PayslipStatus = "draft" | "issued";

export type SalaryItem = {
  id: string;
  name: string;
  itemType: SalaryItemType;
  sortOrder: number;
  enabled: boolean;
  createdAt: string | null;
  createdBy: string | null;
  updatedAt: string | null;
  updatedBy: string | null;
};

export type EmployeeSalaryProfileItem = {
  salaryItemId: string;
  name: string;
  itemType: SalaryItemType;
  sortOrder: number;
  monthlyAmount: number;
};

export type EmployeeSalaryProfileSnapshot = {
  effectiveDate: string;
  createdAt: string | null;
  createdBy: string | null;
  updatedAt: string | null;
  updatedBy: string | null;
  items: EmployeeSalaryProfileItem[];
};

export type PayslipItem = {
  salaryItemId: string;
  name: string;
  itemType: SalaryItemType;
  sortOrder: number;
  amount: number;
};

export type Payslip = {
  id: string;
  employeeId: string;
  payMonth: string | null;
  status: PayslipStatus;
  grossAmount: number;
  deductionAmount: number;
  netAmount: number;
  issuedAt: string | null;
  createdAt: string | null;
  createdBy: string | null;
  updatedAt: string | null;
  updatedBy: string | null;
  employee: {
    id: string;
    employeeNo: string;
    name: string;
    title: string;
    department: {
      id: string;
      name: string;
    } | null;
  } | null;
  items: PayslipItem[];
};

export type PayrollMonthSummary = {
  month: string;
  totalNetAmount: number;
  averageNetAmount: number;
  issuedCount: number;
};

export async function fetchSalaryItems() {
  return apiRequestData<{ items: SalaryItem[] }>("/api/payroll/items");
}

export async function createSalaryItem(payload: {
  name: string;
  itemType: SalaryItemType;
  sortOrder: number;
  enabled?: boolean;
}) {
  return apiRequestData<SalaryItem>("/api/payroll/items", {
    method: "POST",
    body: JSON.stringify(payload),
  });
}

export async function patchSalaryItem(
  itemId: string,
  payload: Partial<{
    name: string;
    itemType: SalaryItemType;
    sortOrder: number;
    enabled: boolean;
  }>,
) {
  return apiRequestData<SalaryItem>(`/api/payroll/items/${itemId}`, {
    method: "PATCH",
    body: JSON.stringify(payload),
  });
}

export async function fetchEmployeeSalaryProfile(employeeId: string) {
  return apiRequestData<{ employeeId: string; snapshots: EmployeeSalaryProfileSnapshot[] }>(
    `/api/payroll/employees/${employeeId}/profile`,
  );
}

export async function upsertEmployeeSalaryProfile(
  employeeId: string,
  payload: {
    effectiveDate: string;
    items: Array<{
      salaryItemId: string;
      monthlyAmount: number;
    }>;
  },
) {
  return apiRequestData<{ employeeId: string; snapshots: EmployeeSalaryProfileSnapshot[] }>(
    `/api/payroll/employees/${employeeId}/profile`,
    {
      method: "PUT",
      body: JSON.stringify(payload),
    },
  );
}

export async function fetchEmployeePayslips(employeeId: string) {
  return apiRequestData<{ employeeId: string; items: Payslip[] }>(`/api/payroll/employees/${employeeId}/payslips`);
}

export async function fetchPayslipsByMonth(month: string) {
  return apiRequestData<{
    month: string;
    salaryItems: SalaryItem[];
    items: Payslip[];
    summary: {
      total: number;
      draft: number;
      issued: number;
    };
  }>(`/api/payroll/payslips?month=${encodeURIComponent(month)}`);
}

export async function generatePayslips(month: string) {
  return apiRequestData<{
    month: string;
    summary: {
      total: number;
      generated: number;
    };
  }>("/api/payroll/payslips/generate", {
    method: "POST",
    body: JSON.stringify({ month }),
  });
}

export async function patchPayslip(
  payslipId: string,
  payload: {
    items: Array<{
      salaryItemId: string;
      amount: number;
    }>;
  },
) {
  return apiRequestData<Payslip>(`/api/payroll/payslips/${payslipId}`, {
    method: "PATCH",
    body: JSON.stringify(payload),
  });
}

export async function issuePayslips(month: string) {
  return apiRequestData<{
    month: string;
    summary: {
      total: number;
      issued: number;
    };
  }>("/api/payroll/payslips/issue", {
    method: "POST",
    body: JSON.stringify({ month }),
  });
}