"use client";

import { useEffect, useMemo, useState } from "react";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { useLocale, useTranslations } from "next-intl";
import { Plus, Trash2 } from "lucide-react";
import { apiDelete, apiGet, apiGetPaged, apiPost } from "@/lib/api/client";
import { useAuthStore } from "@/lib/stores/auth.store";
import { formatCurrency, formatNumber } from "@/lib/format";
import { isoTodayTehran } from "@/lib/reports/analytics";
import { PageHeader } from "@/components/layout/page-header";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { JalaliDateField } from "@/components/ui/jalali-date-field";
import { LabeledField } from "@/components/ui/labeled-field";
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
type Branch = { id: string; name: string };

type ShiftDto = {
  id: string;
  branchId: string;
  status: string;
};

export type ExpenseCategory =
  | "Supplies"
  | "Utilities"
  | "Salary"
  | "Rent"
  | "Maintenance"
  | "Other";

export type ExpenseRow = {
  id: string;
  cafeId: string;
  branchId: string;
  shiftId?: string | null;
  category: ExpenseCategory;
  amount: number;
  note?: string | null;
  receiptImageUrl?: string | null;
  createdByUserId: string;
  createdAt: string;
};

const CATEGORIES: ExpenseCategory[] = [
  "Supplies",
  "Utilities",
  "Salary",
  "Rent",
  "Maintenance",
  "Other",
];

const MANAGER_ROLES = new Set(["Owner", "Manager"]);

export function ExpensesScreen() {
  const t = useTranslations("expenses");
  const tCommon = useTranslations("common");
  const locale = useLocale();
  const numberLocale = locale === "en" ? "en-US" : "fa-IR";
  const cafeId = useAuthStore((s) => s.user?.cafeId);
  const role = useAuthStore((s) => s.user?.role ?? "");
  const queryClient = useQueryClient();

  const today = isoTodayTehran();
  const [branchId, setBranchId] = useState<string>("");
  const [from, setFrom] = useState(today);
  const [to, setTo] = useState(today);
  const [showModal, setShowModal] = useState(false);
  const [category, setCategory] = useState<ExpenseCategory>("Supplies");
  const [amount, setAmount] = useState("");
  const [note, setNote] = useState("");
  const [linkShift, setLinkShift] = useState(true);

  const { data: branches = [] } = useQuery({
    queryKey: ["branches", cafeId],
    queryFn: () => apiGet<Branch[]>(`/api/cafes/${cafeId}/branches`),
    enabled: !!cafeId,
  });

  useEffect(() => {
    if (!branchId && branches.length > 0) setBranchId(branches[0]!.id);
  }, [branchId, branches]);

  const { data: currentShift } = useQuery({
    queryKey: ["shift-current", cafeId, branchId],
    queryFn: async () => {
      try {
        return await apiGet<ShiftDto>(
          `/api/cafes/${cafeId}/branches/${branchId}/shifts/current`
        );
      } catch {
        return null;
      }
    },
    enabled: !!cafeId && !!branchId,
  });

  const listKey = ["expenses", cafeId, branchId, from, to] as const;

  const { data: listResponse, isLoading } = useQuery({
    queryKey: listKey,
    queryFn: () =>
      apiGetPaged<ExpenseRow>(
        `/api/cafes/${cafeId}/expenses?branchId=${encodeURIComponent(branchId)}&from=${from}&to=${to}&page=1&pageSize=50`
      ),
    enabled: !!cafeId && !!branchId && !!from && !!to,
  });

  const rows = useMemo(() => listResponse?.items ?? [], [listResponse?.items]);
  const totalAmount = useMemo(() => rows.reduce((s, r) => s + r.amount, 0), [rows]);

  const createExpense = useMutation({
    mutationFn: () =>
      apiPost<ExpenseRow>(`/api/cafes/${cafeId}/expenses`, {
        branchId,
        shiftId: linkShift && currentShift ? currentShift.id : null,
        category,
        amount: Number(amount),
        note: note.trim() || null,
        receiptImageUrl: null,
      }),
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey: listKey });
      setShowModal(false);
      setAmount("");
      setNote("");
      setCategory("Supplies");
    },
  });

  const deleteExpense = useMutation({
    mutationFn: (id: string) => apiDelete(`/api/cafes/${cafeId}/expenses/${id}`),
    onSuccess: () => queryClient.invalidateQueries({ queryKey: listKey }),
  });

  const canDelete = MANAGER_ROLES.has(role);

  if (!cafeId) return null;

  return (
    <div className="space-y-6 bg-[#f5f5f4] min-h-full -m-4 p-4 md:-m-6 md:p-6">
      <PageHeader
        title={t("title")}
        subtitle={t("subtitle")}
        action={
          <Button
            className="bg-[#0F6E56] hover:bg-[#0d5e49]"
            onClick={() => setShowModal(true)}
            disabled={!branchId}
          >
            <Plus className="ms-2 h-4 w-4" />
            {t("addExpense")}
          </Button>
        }
      />

      <Card className="rounded-xl border border-border/80 bg-card">
        <CardContent className="flex flex-wrap items-end gap-4 pt-6">
          <LabeledField label={t("branch")} htmlFor="exp-branch">
            <select
              id="exp-branch"
              className="h-9 min-w-[10rem] rounded-md border border-input bg-background px-3 text-sm"
              value={branchId}
              onChange={(e) => setBranchId(e.target.value)}
            >
              {branches.map((b) => (
                <option key={b.id} value={b.id}>
                  {b.name}
                </option>
              ))}
            </select>
          </LabeledField>
          <LabeledField label={t("fromDate")} htmlFor="exp-from">
            <JalaliDateField id="exp-from" className="w-40" value={from} onChange={setFrom} />
          </LabeledField>
          <LabeledField label={t("toDate")} htmlFor="exp-to">
            <JalaliDateField id="exp-to" className="w-40" value={to} onChange={setTo} />
          </LabeledField>
          <div className="ms-auto text-end">
            <p className="text-[11px] font-medium uppercase tracking-[0.06em] text-muted-foreground">
              {t("periodTotal")}
            </p>
            <p className="text-lg font-semibold text-[#BA7517]">
              {formatCurrency(totalAmount, numberLocale)}
            </p>
          </div>
        </CardContent>
      </Card>

      <Card className="rounded-xl border border-border/80 bg-card">
        <CardHeader>
          <CardTitle className="text-base">{t("listTitle")}</CardTitle>
        </CardHeader>
        <CardContent className="overflow-x-auto">
          <table className="w-full min-w-[28rem] text-sm">
            <thead>
              <tr className="border-b text-[11px] font-medium uppercase tracking-[0.06em] text-muted-foreground">
                <th className="py-2 text-start">{t("colDate")}</th>
                <th className="py-2 text-start">{t("colCategory")}</th>
                <th className="py-2 text-start">{t("colNote")}</th>
                <th className="py-2 text-end">{t("colAmount")}</th>
                {canDelete ? <th className="py-2 w-10" /> : null}
              </tr>
            </thead>
            <tbody>
              {isLoading ? (
                <tr>
                  <td colSpan={canDelete ? 5 : 4} className="py-4 text-muted-foreground">
                    {t("loading")}
                  </td>
                </tr>
              ) : rows.length === 0 ? (
                <tr>
                  <td colSpan={canDelete ? 5 : 4} className="py-4 text-muted-foreground">
                    {t("empty")}
                  </td>
                </tr>
              ) : (
                rows.map((row) => (
                  <tr key={row.id} className="border-b border-border/50">
                    <td className="py-2.5 tabular-nums text-muted-foreground" dir="ltr">
                      {new Date(row.createdAt).toLocaleString(
                        locale === "en" ? "en-GB" : "fa-IR",
                        { dateStyle: "short", timeStyle: "short" }
                      )}
                    </td>
                    <td className="py-2.5">{t(`categories.${row.category}`)}</td>
                    <td className="py-2.5 max-w-[12rem] truncate text-muted-foreground">
                      {row.note ?? "—"}
                    </td>
                    <td className="py-2.5 text-end font-medium text-[#BA7517] tabular-nums">
                      {formatCurrency(row.amount, numberLocale)}
                    </td>
                    {canDelete ? (
                      <td className="py-2.5 text-end">
                        <Button
                          variant="ghost"
                          size="icon"
                          className="h-8 w-8 text-[#A32D2D]"
                          onClick={() => deleteExpense.mutate(row.id)}
                          disabled={deleteExpense.isPending}
                          aria-label={tCommon("delete")}
                        >
                          <Trash2 className="h-4 w-4" />
                        </Button>
                      </td>
                    ) : null}
                  </tr>
                ))
              )}
            </tbody>
          </table>
          {listResponse?.meta ? (
            <p className="mt-3 text-xs text-muted-foreground">
              {t("rowCount", {
                count: formatNumber(listResponse.meta.total, numberLocale),
              })}
            </p>
          ) : null}
        </CardContent>
      </Card>

      {showModal ? (
        <div
          className="fixed inset-0 z-50 flex items-center justify-center bg-black/40 p-4"
          role="dialog"
          aria-modal="true"
          aria-labelledby="expense-modal-title"
        >
          <Card className="w-full max-w-md rounded-xl border border-border/80 bg-card shadow-lg">
            <CardHeader>
              <CardTitle id="expense-modal-title" className="text-base">
                {t("addExpense")}
              </CardTitle>
            </CardHeader>
            <CardContent className="space-y-4">
              <LabeledField label={t("category")} htmlFor="exp-cat">
                <select
                  id="exp-cat"
                  className="h-9 w-full rounded-md border border-input bg-background px-3 text-sm"
                  value={category}
                  onChange={(e) => setCategory(e.target.value as ExpenseCategory)}
                >
                  {CATEGORIES.map((c) => (
                    <option key={c} value={c}>
                      {t(`categories.${c}`)}
                    </option>
                  ))}
                </select>
              </LabeledField>
              <LabeledField label={t("amount")} htmlFor="exp-amount">
                <Input
                  id="exp-amount"
                  type="number"
                  min={1}
                  dir="ltr"
                  className="text-end"
                  value={amount}
                  onChange={(e) => setAmount(e.target.value)}
                />
              </LabeledField>
              <LabeledField label={t("note")} htmlFor="exp-note">
                <Input
                  id="exp-note"
                  value={note}
                  onChange={(e) => setNote(e.target.value)}
                  placeholder={t("notePlaceholder")}
                />
              </LabeledField>
              {currentShift ? (
                <label className="flex items-center gap-2 text-sm">
                  <input
                    type="checkbox"
                    checked={linkShift}
                    onChange={(e) => setLinkShift(e.target.checked)}
                  />
                  {t("linkOpenShift")}
                </label>
              ) : (
                <p className="text-xs text-muted-foreground">{t("noOpenShift")}</p>
              )}
              <div className="flex gap-2 pt-2">
                <Button
                  className="bg-[#0F6E56] hover:bg-[#0d5e49]"
                  disabled={!amount || createExpense.isPending}
                  onClick={() => createExpense.mutate()}
                >
                  {tCommon("confirm")}
                </Button>
                <Button variant="outline" onClick={() => setShowModal(false)}>
                  {tCommon("cancel")}
                </Button>
              </div>
            </CardContent>
          </Card>
        </div>
      ) : null}
    </div>
  );
}