"use client";

import { useEffect, useState } from "react";
import Link from "next/link";
import { 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 { CheckCircle2, Circle, X, Download, Eye } from "lucide-react";
import { accountingApi, type CoaTemplate } from "@/lib/accounting-api";
import { useTenantId } from "@/hooks/useTenantId";
import {
  PageHeader,
  Button,
  Card,
  CardContent,
  CardHeader,
  CardTitle,
  Badge,
  LoadingState,
  ErrorState,
  Dialog,
  Input,
  Label,
  FieldError,
  DataTable,
  EmptyState,
} from "@/components/ds";
import { CompletionScoreboard } from "@/components/accounting/CompletionScoreboard";

const TOUR_KEY = "accounting-setup-tour-dismissed";

const importSchema = z.object({
  chart_name: z.string().min(1, "نام دفتر الزامی است"),
  chart_code: z.string().min(1, "کد دفتر الزامی است"),
});

type SetupStep = {
  key: keyof typeof STEP_LINKS;
  label: string;
  done: boolean;
};

const STEP_LINKS = {
  has_chart: { href: "/accounting/chart-of-accounts", label: "دفتر حساب‌ها" },
  has_accounts: { href: "/accounting/chart-of-accounts", label: "حساب‌ها" },
  has_currency: { href: "/accounting/currencies", label: "ارزها" },
  has_base_currency: { href: "/accounting/currencies", label: "ارز پایه" },
  has_fiscal_year: { href: "/accounting/fiscal", label: "سال مالی" },
  has_fiscal_period: { href: "/accounting/fiscal", label: "دوره مالی" },
  has_cash_box: { href: "/accounting/treasury/cash-boxes", label: "صندوق" },
  has_customer: { href: "/accounting/customers", label: "مشتری" },
  has_voucher: { href: "/accounting/vouchers", label: "سند حسابداری" },
} as const;

export default function SetupPage() {
  const { tenantId } = useTenantId();
  const qc = useQueryClient();
  const [showTour, setShowTour] = useState(false);
  const [previewTemplate, setPreviewTemplate] = useState<CoaTemplate | null>(null);
  const [importTemplate, setImportTemplate] = useState<CoaTemplate | null>(null);

  useEffect(() => {
    if (typeof window === "undefined") return;
    setShowTour(localStorage.getItem(TOUR_KEY) !== "1");
  }, []);

  const dismissTour = () => {
    localStorage.setItem(TOUR_KEY, "1");
    setShowTour(false);
  };

  const statusQ = useQuery({
    queryKey: ["accounting", tenantId, "setup-status"],
    queryFn: () => accountingApi.setup.status(tenantId!),
    enabled: !!tenantId,
  });

  const templatesQ = useQuery({
    queryKey: ["accounting", tenantId, "coa-templates"],
    queryFn: () => accountingApi.templates.list(tenantId!),
    enabled: !!tenantId,
  });

  const importForm = useForm<z.infer<typeof importSchema>>({
    resolver: zodResolver(importSchema),
    defaultValues: { chart_name: "", chart_code: "" },
  });

  const importM = useMutation({
    mutationFn: (d: z.infer<typeof importSchema>) =>
      accountingApi.templates.import(tenantId!, importTemplate!.id, d),
    onSuccess: async (accounts) => {
      toast.success(`${accounts.length} حساب از قالب وارد شد`);
      setImportTemplate(null);
      importForm.reset();
      await qc.invalidateQueries({ queryKey: ["accounting", tenantId, "setup-status"] });
      await qc.invalidateQueries({ queryKey: ["accounting", tenantId, "charts"] });
      await qc.invalidateQueries({ queryKey: ["accounting", tenantId, "accounts"] });
    },
    onError: (e: Error) => toast.error(e.message),
  });

  if (!tenantId || statusQ.isLoading) return <LoadingState />;
  if (statusQ.error) {
    return <ErrorState message={statusQ.error.message} onRetry={() => statusQ.refetch()} />;
  }

  const s = statusQ.data!;
  const steps: SetupStep[] = [
    { key: "has_chart", label: "ایجاد دفتر حساب", done: s.has_chart },
    { key: "has_accounts", label: "تعریف حساب‌ها", done: s.has_accounts },
    { key: "has_currency", label: "تعریف ارز", done: s.has_currency },
    { key: "has_base_currency", label: "تعیین ارز پایه", done: s.has_base_currency },
    { key: "has_fiscal_year", label: "سال مالی", done: s.has_fiscal_year },
    { key: "has_fiscal_period", label: "دوره مالی", done: s.has_fiscal_period },
    { key: "has_cash_box", label: "صندوق خزانه", done: s.has_cash_box },
    { key: "has_customer", label: "مشتری", done: s.has_customer },
    { key: "has_voucher", label: "اولین سند", done: s.has_voucher },
  ];

  return (
    <div>
      <PageHeader
        title="راه‌اندازی حسابداری"
        description={`${s.completed_steps} از ${s.total_steps} مرحله — ${s.percent}٪ تکمیل`}
        actions={
          <Badge tone={s.percent >= 100 ? "success" : "primary"}>{s.percent}٪</Badge>
        }
      />

      {showTour ? (
        <Card className="mb-6 border-primary/30 bg-primary/5">
          <CardContent className="flex flex-col gap-3 pt-5 sm:flex-row sm:items-start sm:justify-between">
            <div>
              <p className="font-semibold text-secondary">به ماژول حسابداری خوش آمدید</p>
              <p className="mt-1 text-sm text-[var(--muted)]">
                این چک‌لیست مراحل اولیه را نشان می‌دهد. می‌توانید از قالب آماده دفتر حساب وارد کنید یا
                هر مرحله را از منو تکمیل کنید.
              </p>
            </div>
            <Button type="button" variant="ghost" size="sm" onClick={dismissTour}>
              <X className="h-4 w-4" />
              دیگر نشان نده
            </Button>
          </CardContent>
        </Card>
      ) : null}

      <div className="grid gap-6 lg:grid-cols-2">
        <Card>
          <CardHeader>
            <CardTitle>چک‌لیست راه‌اندازی</CardTitle>
          </CardHeader>
          <CardContent className="space-y-2">
            {steps.map((step) => {
              const link = STEP_LINKS[step.key];
              return (
                <Link
                  key={step.key}
                  href={link.href}
                  className="flex items-center gap-3 rounded-xl px-3 py-2.5 hover:bg-[var(--surface-muted)]"
                >
                  {step.done ? (
                    <CheckCircle2 className="h-5 w-5 shrink-0 text-emerald-600" />
                  ) : (
                    <Circle className="h-5 w-5 shrink-0 text-[var(--muted)]" />
                  )}
                  <span className="flex-1 text-sm font-medium text-secondary">{step.label}</span>
                  <Badge tone={step.done ? "success" : "default"}>{step.done ? "انجام شد" : "باقی‌مانده"}</Badge>
                </Link>
              );
            })}
          </CardContent>
        </Card>

        <CompletionScoreboard />
      </div>

      <Card className="mt-6">
        <CardHeader>
          <CardTitle>ویزارد قالب دفتر حساب (COA)</CardTitle>
        </CardHeader>
        <CardContent>
          {templatesQ.isLoading ? (
            <LoadingState />
          ) : templatesQ.error ? (
            <ErrorState message={templatesQ.error.message} onRetry={() => templatesQ.refetch()} />
          ) : !(templatesQ.data ?? []).length ? (
            <EmptyState title="قالبی در سرور موجود نیست" />
          ) : (
            <div className="grid gap-3 sm:grid-cols-2">
              {(templatesQ.data ?? []).map((t) => (
                <div
                  key={t.id}
                  className="rounded-2xl border border-[var(--border)] bg-[var(--surface)] p-4"
                >
                  <p className="font-semibold text-secondary">{t.name}</p>
                  <p className="mt-1 text-sm text-[var(--muted)]">{t.description}</p>
                  <p className="mt-2 text-xs text-[var(--muted)]">
                    {t.accounts.length} حساب · {t.business_type}
                  </p>
                  <div className="mt-3 flex flex-wrap gap-2">
                    <Button
                      type="button"
                      size="sm"
                      variant="outline"
                      onClick={() => setPreviewTemplate(t)}
                    >
                      <Eye className="h-3.5 w-3.5" />
                      پیش‌نمایش
                    </Button>
                    <Button
                      type="button"
                      size="sm"
                      onClick={() => {
                        setImportTemplate(t);
                        importForm.reset({
                          chart_name: t.name,
                          chart_code: t.business_type.slice(0, 8).toUpperCase(),
                        });
                      }}
                    >
                      <Download className="h-3.5 w-3.5" />
                      وارد کردن
                    </Button>
                  </div>
                </div>
              ))}
            </div>
          )}
        </CardContent>
      </Card>

      <Dialog
        open={!!previewTemplate}
        onClose={() => setPreviewTemplate(null)}
        title={previewTemplate?.name ?? "پیش‌نمایش قالب"}
      >
        {previewTemplate ? (
          <DataTable
            columns={[
              { key: "code", header: "کد" },
              { key: "name", header: "نام" },
              { key: "account_type", header: "نوع" },
              { key: "level", header: "سطح" },
              {
                key: "is_postable",
                header: "قابل ثبت",
                render: (r) => (r.is_postable ? "بله" : "خیر"),
              },
            ]}
            rows={previewTemplate.accounts as unknown as Record<string, unknown>[]}
          />
        ) : null}
      </Dialog>

      <Dialog open={!!importTemplate} onClose={() => setImportTemplate(null)} title="وارد کردن قالب">
        <form
          className="space-y-3"
          onSubmit={importForm.handleSubmit((d) => importM.mutate(d))}
        >
          <p className="text-sm text-[var(--muted)]">
            قالب «{importTemplate?.name}» — {importTemplate?.accounts.length} حساب
          </p>
          <div>
            <Label>نام دفتر</Label>
            <Input {...importForm.register("chart_name")} />
            <FieldError>{importForm.formState.errors.chart_name?.message}</FieldError>
          </div>
          <div>
            <Label>کد دفتر</Label>
            <Input {...importForm.register("chart_code")} dir="ltr" />
            <FieldError>{importForm.formState.errors.chart_code?.message}</FieldError>
          </div>
          <div className="flex justify-end gap-2">
            <Button type="button" variant="outline" onClick={() => setImportTemplate(null)}>
              انصراف
            </Button>
            <Button type="submit" disabled={importM.isPending}>
              وارد کردن
            </Button>
          </div>
        </form>
      </Dialog>
    </div>
  );
}