"use client";

import { useState } from "react";
import { Controller, useForm } from "react-hook-form";
import { z } from "zod";
import { zodResolver } from "@hookform/resolvers/zod";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { toast } from "sonner";
import { Calculator, Plus } from "lucide-react";
import { accountingApi } from "@/lib/accounting-api";
import { useTenantId } from "@/hooks/useTenantId";
import { formatMoney } from "@/lib/utils";
import {
  PageHeader,
  Button,
  Dialog,
  Input,
  DataTable,
  EmptyState,
  LoadingState,
  ErrorState,
  Badge,
  Tabs,
  FormField,
  Select,
  MoneyInput,
  DatePicker,
  JalaliDateText,
  Card,
  CardContent,
  CardHeader,
  CardTitle,
} from "@/components/ds";

const deptSchema = z.object({
  code: z.string().min(1, "کد الزامی است"),
  name: z.string().min(1, "نام الزامی است"),
});

const employeeSchema = z.object({
  employee_code: z.string().min(1, "کد پرسنلی الزامی است"),
  first_name: z.string().min(1, "نام الزامی است"),
  last_name: z.string().min(1, "نام خانوادگی الزامی است"),
  base_salary: z.string().optional(),
  department_id: z.string().optional(),
});

const periodSchema = z.object({
  name: z.string().min(1, "نام دوره الزامی است"),
  start_date: z.string().min(1, "تاریخ شروع الزامی است"),
  end_date: z.string().min(1, "تاریخ پایان الزامی است"),
});

const calcSchema = z.object({
  payroll_period_id: z.string().min(1, "دوره حقوق را انتخاب کنید"),
  employee_id: z.string().min(1, "کارمند را انتخاب کنید"),
});

type TabId = "departments" | "employees" | "periods" | "operations";

export default function PayrollPage() {
  const { tenantId } = useTenantId();
  const qc = useQueryClient();
  const [tab, setTab] = useState<TabId>("employees");
  const [deptOpen, setDeptOpen] = useState(false);
  const [employeeOpen, setEmployeeOpen] = useState(false);
  const [periodOpen, setPeriodOpen] = useState(false);
  const [lastPayroll, setLastPayroll] = useState<{
    id: string;
    gross_salary: string;
    net_salary: string;
    status: string;
  } | null>(null);

  const departmentsQ = useQuery({
    queryKey: ["accounting", tenantId, "payroll-departments"],
    queryFn: () => accountingApi.payroll.listDepartments(tenantId!),
    enabled: !!tenantId,
  });
  const employeesQ = useQuery({
    queryKey: ["accounting", tenantId, "employees"],
    queryFn: () => accountingApi.payroll.listEmployees(tenantId!),
    enabled: !!tenantId,
  });
  const periodsQ = useQuery({
    queryKey: ["accounting", tenantId, "payroll-periods"],
    queryFn: () => accountingApi.payroll.listPeriods(tenantId!),
    enabled: !!tenantId,
  });

  const deptForm = useForm<z.infer<typeof deptSchema>>({
    resolver: zodResolver(deptSchema),
    defaultValues: { code: "", name: "" },
  });
  const employeeForm = useForm<z.infer<typeof employeeSchema>>({
    resolver: zodResolver(employeeSchema),
    defaultValues: { employee_code: "", first_name: "", last_name: "", base_salary: "0", department_id: "" },
  });
  const periodForm = useForm<z.infer<typeof periodSchema>>({
    resolver: zodResolver(periodSchema),
    defaultValues: { name: "", start_date: "", end_date: "" },
  });
  const calcForm = useForm<z.infer<typeof calcSchema>>({
    resolver: zodResolver(calcSchema),
    defaultValues: { payroll_period_id: "", employee_id: "" },
  });

  const invalidateDepts = () =>
    qc.invalidateQueries({ queryKey: ["accounting", tenantId, "payroll-departments"] });
  const invalidateEmployees = () =>
    qc.invalidateQueries({ queryKey: ["accounting", tenantId, "employees"] });
  const invalidatePeriods = () =>
    qc.invalidateQueries({ queryKey: ["accounting", tenantId, "payroll-periods"] });

  const createDeptM = useMutation({
    mutationFn: (d: z.infer<typeof deptSchema>) => accountingApi.payroll.createDepartment(tenantId!, d),
    onSuccess: async () => {
      toast.success("واحد سازمانی ثبت شد");
      setDeptOpen(false);
      deptForm.reset();
      await invalidateDepts();
    },
    onError: (e: Error) => toast.error(e.message),
  });

  const createEmployeeM = useMutation({
    mutationFn: (d: z.infer<typeof employeeSchema>) =>
      accountingApi.payroll.createEmployee(tenantId!, {
        employee_code: d.employee_code,
        first_name: d.first_name,
        last_name: d.last_name,
        base_salary: d.base_salary,
        department_id: d.department_id || undefined,
      }),
    onSuccess: async () => {
      toast.success("کارمند ثبت شد");
      setEmployeeOpen(false);
      employeeForm.reset();
      await invalidateEmployees();
    },
    onError: (e: Error) => toast.error(e.message),
  });

  const createPeriodM = useMutation({
    mutationFn: (d: z.infer<typeof periodSchema>) => accountingApi.payroll.createPeriod(tenantId!, d),
    onSuccess: async () => {
      toast.success("دوره حقوق ایجاد شد");
      setPeriodOpen(false);
      periodForm.reset();
      await invalidatePeriods();
    },
    onError: (e: Error) => toast.error(e.message),
  });

  const calculateM = useMutation({
    mutationFn: (d: z.infer<typeof calcSchema>) => accountingApi.payroll.calculate(tenantId!, d),
    onSuccess: (res) => {
      setLastPayroll(res);
      toast.success("حقوق محاسبه شد");
    },
    onError: (e: Error) => toast.error(e.message),
  });

  const postM = useMutation({
    mutationFn: (payrollId: string) => accountingApi.payroll.post(tenantId!, payrollId),
    onSuccess: (res) => {
      toast.success("حقوق ثبت حسابداری شد");
      setLastPayroll((prev) => (prev ? { ...prev, status: res.status } : prev));
    },
    onError: (e: Error) => toast.error(e.message),
  });

  if (!tenantId) return <LoadingState />;
  const loading = departmentsQ.isLoading || employeesQ.isLoading || periodsQ.isLoading;
  if (loading) return <LoadingState />;
  const err = departmentsQ.error || employeesQ.error || periodsQ.error;
  if (err) {
    return (
      <ErrorState
        message={err instanceof Error ? err.message : "خطا"}
        onRetry={() => {
          void departmentsQ.refetch();
          void employeesQ.refetch();
          void periodsQ.refetch();
        }}
      />
    );
  }

  const tabActions: Record<TabId, React.ReactNode> = {
    departments: (
      <Button onClick={() => setDeptOpen(true)}>
        <Plus className="h-4 w-4" />
        واحد جدید
      </Button>
    ),
    employees: (
      <Button onClick={() => setEmployeeOpen(true)}>
        <Plus className="h-4 w-4" />
        کارمند جدید
      </Button>
    ),
    periods: (
      <Button onClick={() => setPeriodOpen(true)}>
        <Plus className="h-4 w-4" />
        دوره جدید
      </Button>
    ),
    operations: null,
  };

  const periodStatusTone = (s: string) =>
    s === "open" ? "success" : s === "closed" ? "danger" : "default";

  return (
    <div>
      <PageHeader
        title="حقوق و دستمزد"
        description="واحدها، کارکنان، دوره‌ها و ثبت حقوق."
        actions={tabActions[tab]}
      />

      <Tabs
        className="mb-6"
        value={tab}
        onChange={(id) => setTab(id as TabId)}
        items={[
          { id: "departments", label: "واحدها" },
          { id: "employees", label: "کارکنان" },
          { id: "periods", label: "دوره‌ها" },
          { id: "operations", label: "محاسبه و ثبت" },
        ]}
      />

      {tab === "departments" && (
        <DataTable
          columns={[
            { key: "code", header: "کد" },
            { key: "name", header: "نام" },
          ]}
          rows={(departmentsQ.data ?? []) as unknown as Record<string, unknown>[]}
          empty={<EmptyState action={<Button onClick={() => setDeptOpen(true)}>ثبت واحد</Button>} />}
        />
      )}

      {tab === "employees" && (
        <DataTable
          columns={[
            { key: "code", header: "کد" },
            { key: "name", header: "نام" },
          ]}
          rows={(employeesQ.data ?? []) as unknown as Record<string, unknown>[]}
          empty={<EmptyState action={<Button onClick={() => setEmployeeOpen(true)}>ثبت کارمند</Button>} />}
        />
      )}

      {tab === "periods" && (
        <DataTable
          columns={[
            { key: "name", header: "نام" },
            {
              key: "start_date",
              header: "شروع",
              render: (r) => <JalaliDateText value={String(r.start_date ?? "")} />,
            },
            {
              key: "end_date",
              header: "پایان",
              render: (r) => <JalaliDateText value={String(r.end_date ?? "")} />,
            },
            {
              key: "status",
              header: "وضعیت",
              render: (r) => (
                <Badge tone={periodStatusTone(String(r.status))}>{String(r.status)}</Badge>
              ),
            },
          ]}
          rows={(periodsQ.data ?? []) as unknown as Record<string, unknown>[]}
          empty={<EmptyState action={<Button onClick={() => setPeriodOpen(true)}>ایجاد دوره</Button>} />}
        />
      )}

      {tab === "operations" && (
        <div className="grid gap-6 lg:grid-cols-2">
          <Card>
            <CardHeader>
              <CardTitle className="flex items-center gap-2">
                <Calculator className="h-4 w-4" />
                محاسبه حقوق
              </CardTitle>
            </CardHeader>
            <CardContent>
              <form className="space-y-3" onSubmit={calcForm.handleSubmit((d) => calculateM.mutate(d))}>
                <FormField label="دوره حقوق" error={calcForm.formState.errors.payroll_period_id?.message}>
                  <Select {...calcForm.register("payroll_period_id")}>
                    <option value="">انتخاب دوره</option>
                    {(periodsQ.data ?? []).map((p) => (
                      <option key={p.id} value={p.id}>
                        {p.name}
                      </option>
                    ))}
                  </Select>
                </FormField>
                <FormField label="کارمند" error={calcForm.formState.errors.employee_id?.message}>
                  <Select {...calcForm.register("employee_id")}>
                    <option value="">انتخاب کارمند</option>
                    {(employeesQ.data ?? []).map((e) => (
                      <option key={e.id} value={e.id}>
                        {e.code} — {e.name}
                      </option>
                    ))}
                  </Select>
                </FormField>
                <Button type="submit" disabled={calculateM.isPending} className="w-full sm:w-auto">
                  محاسبه
                </Button>
              </form>
            </CardContent>
          </Card>

          {lastPayroll && (
            <Card>
              <CardHeader>
                <CardTitle>نتیجه محاسبه</CardTitle>
              </CardHeader>
              <CardContent className="space-y-3 text-sm">
                <div className="flex justify-between">
                  <span className="text-[var(--muted)]">ناخالص</span>
                  <span className="font-medium">{formatMoney(lastPayroll.gross_salary)}</span>
                </div>
                <div className="flex justify-between">
                  <span className="text-[var(--muted)]">خالص</span>
                  <span className="font-medium">{formatMoney(lastPayroll.net_salary)}</span>
                </div>
                <div className="flex justify-between">
                  <span className="text-[var(--muted)]">وضعیت</span>
                  <Badge>{lastPayroll.status}</Badge>
                </div>
                <Button
                  type="button"
                  className="w-full"
                  disabled={postM.isPending || lastPayroll.status === "posted"}
                  onClick={() => postM.mutate(lastPayroll.id)}
                >
                  ثبت حسابداری (Post)
                </Button>
              </CardContent>
            </Card>
          )}
        </div>
      )}

      <Dialog open={deptOpen} onClose={() => setDeptOpen(false)} title="واحد سازمانی جدید">
        <form className="space-y-3" onSubmit={deptForm.handleSubmit((d) => createDeptM.mutate(d))}>
          <FormField label="کد" error={deptForm.formState.errors.code?.message}>
            <Input {...deptForm.register("code")} />
          </FormField>
          <FormField label="نام" error={deptForm.formState.errors.name?.message}>
            <Input {...deptForm.register("name")} />
          </FormField>
          <div className="flex justify-end gap-2">
            <Button type="button" variant="outline" onClick={() => setDeptOpen(false)}>
              انصراف
            </Button>
            <Button type="submit" disabled={createDeptM.isPending}>
              ذخیره
            </Button>
          </div>
        </form>
      </Dialog>

      <Dialog open={employeeOpen} onClose={() => setEmployeeOpen(false)} title="کارمند جدید">
        <form className="space-y-3" onSubmit={employeeForm.handleSubmit((d) => createEmployeeM.mutate(d))}>
          <FormField label="کد پرسنلی" error={employeeForm.formState.errors.employee_code?.message}>
            <Input {...employeeForm.register("employee_code")} />
          </FormField>
          <div className="grid grid-cols-2 gap-3">
            <FormField label="نام" error={employeeForm.formState.errors.first_name?.message}>
              <Input {...employeeForm.register("first_name")} />
            </FormField>
            <FormField label="نام خانوادگی" error={employeeForm.formState.errors.last_name?.message}>
              <Input {...employeeForm.register("last_name")} />
            </FormField>
          </div>
          <FormField label="واحد">
            <Select {...employeeForm.register("department_id")}>
              <option value="">بدون واحد</option>
              {(departmentsQ.data ?? []).map((d) => (
                <option key={d.id} value={d.id}>
                  {d.code} — {d.name}
                </option>
              ))}
            </Select>
          </FormField>
          <FormField label="حقوق پایه">
            <MoneyInput {...employeeForm.register("base_salary")} />
          </FormField>
          <div className="flex justify-end gap-2">
            <Button type="button" variant="outline" onClick={() => setEmployeeOpen(false)}>
              انصراف
            </Button>
            <Button type="submit" disabled={createEmployeeM.isPending}>
              ذخیره
            </Button>
          </div>
        </form>
      </Dialog>

      <Dialog open={periodOpen} onClose={() => setPeriodOpen(false)} title="دوره حقوق جدید">
        <form className="space-y-3" onSubmit={periodForm.handleSubmit((d) => createPeriodM.mutate(d))}>
          <FormField label="نام دوره" error={periodForm.formState.errors.name?.message}>
            <Input {...periodForm.register("name")} />
          </FormField>
          <div className="grid grid-cols-2 gap-3">
            <FormField label="شروع" error={periodForm.formState.errors.start_date?.message}>
              <Controller
                control={periodForm.control}
                name="start_date"
                render={({ field }) => (
                  <DatePicker
                    value={field.value}
                    onChange={field.onChange}
                    onBlur={field.onBlur}
                    name={field.name}
                  />
                )}
              />
            </FormField>
            <FormField label="پایان" error={periodForm.formState.errors.end_date?.message}>
              <Controller
                control={periodForm.control}
                name="end_date"
                render={({ field }) => (
                  <DatePicker
                    value={field.value}
                    onChange={field.onChange}
                    onBlur={field.onBlur}
                    name={field.name}
                  />
                )}
              />
            </FormField>
          </div>
          <div className="flex justify-end gap-2">
            <Button type="button" variant="outline" onClick={() => setPeriodOpen(false)}>
              انصراف
            </Button>
            <Button type="submit" disabled={createPeriodM.isPending}>
              ذخیره
            </Button>
          </div>
        </form>
      </Dialog>
    </div>
  );
}
