"use client";

import { useState, useEffect, useCallback, useRef } from "react";
import { useSession } from "next-auth/react";
import {
  FileText,
  Download,
  RefreshCw,
  Loader2,
  Clock,
  Archive,
  CreditCard,
  Search,
} from "lucide-react";
import { Button } from "@/shared/components/ui/button";
import { Input } from "@/shared/components/ui/input";
import { Badge } from "@/shared/components/ui/badge";
import { Card, CardContent } from "@/shared/components/ui/card";
import {
  Tooltip,
  TooltipContent,
  TooltipProvider,
  TooltipTrigger,
} from "@/shared/components/ui/tooltip";
import { cn } from "@/shared/lib/utils";
import type { EpaySessionStatus } from "./epay-connect";
import {
  cfDownloadUrl,
  fetchCfOrdersList,
  placeCfOrder,
  type CfExtractRecord,
} from "./cf-api-base";

type GisUatResult = {
  siruta: string;
  name: string;
  county: string | null;
};

/* ------------------------------------------------------------------ */
/*  Helpers                                                            */
/* ------------------------------------------------------------------ */

function formatDate(iso?: string | null) {
  if (!iso) return "—";
  return new Date(iso).toLocaleDateString("ro-RO", {
    day: "2-digit",
    month: "2-digit",
    year: "numeric",
    hour: "2-digit",
    minute: "2-digit",
  });
}

function formatShortDate(iso?: string | null) {
  if (!iso) return "—";
  return new Date(iso).toLocaleDateString("ro-RO", {
    day: "2-digit",
    month: "2-digit",
    year: "numeric",
  });
}

function isExpired(expiresAt: string | null): boolean {
  if (!expiresAt) return false;
  return new Date(expiresAt) < new Date();
}

function isActiveStatus(status: string): boolean {
  return ["pending", "queued", "cart", "searching", "ordering", "polling", "downloading"].includes(
    status,
  );
}

type StatusStyle = { label: string; className: string; pulse?: boolean };

function statusBadge(status: string, expiresAt: string | null): StatusStyle {
  if (status === "completed" && isExpired(expiresAt)) {
    return {
      label: "Expirat",
      className:
        "bg-orange-100 text-orange-700 border-orange-200 dark:bg-orange-950/40 dark:text-orange-400 dark:border-orange-800",
    };
  }

  switch (status) {
    case "pending":
    case "queued":
      return {
        label: "In coada",
        className:
          "bg-muted text-muted-foreground border-muted-foreground/20",
      };
    case "cart":
    case "searching":
    case "ordering":
    case "polling":
    case "downloading":
      return {
        label: "Se proceseaza",
        className:
          "bg-yellow-100 text-yellow-700 border-yellow-200 dark:bg-yellow-950/40 dark:text-yellow-400 dark:border-yellow-800",
        pulse: true,
      };
    case "completed":
      return {
        label: "Valid",
        className:
          "bg-emerald-100 text-emerald-700 border-emerald-200 dark:bg-emerald-950/40 dark:text-emerald-400 dark:border-emerald-800",
      };
    case "failed":
      return {
        label: "Eroare",
        className:
          "bg-rose-100 text-rose-700 border-rose-200 dark:bg-rose-950/40 dark:text-rose-400 dark:border-rose-800",
      };
    case "cancelled":
      return {
        label: "Anulat",
        className:
          "bg-muted text-muted-foreground border-muted-foreground/20",
      };
    default:
      return {
        label: status,
        className:
          "bg-muted text-muted-foreground border-muted-foreground/20",
      };
  }
}

/* ------------------------------------------------------------------ */
/*  Filter tabs                                                        */
/* ------------------------------------------------------------------ */

type FilterValue = "all" | "valid" | "expired" | "active";

const FILTER_OPTIONS: { value: FilterValue; label: string }[] = [
  { value: "all", label: "Toate" },
  { value: "valid", label: "Valabile" },
  { value: "expired", label: "Expirate" },
  { value: "active", label: "In procesare" },
];

/* ------------------------------------------------------------------ */
/*  Component                                                          */
/* ------------------------------------------------------------------ */

export function EpayTab() {
  /* -- Cutover flag (Plan 003, Faza F) ----------------------------- */
  const { data: session } = useSession();
  const useGisAc = Boolean(
    (session as { useGisAc?: boolean } | null)?.useGisAc,
  );

  /* -- ePay session ------------------------------------------------ */
  const [epayStatus, setEpayStatus] = useState<EpaySessionStatus>({
    connected: false,
  });

  /* -- Orders list ------------------------------------------------- */
  const [orders, setOrders] = useState<CfExtractRecord[]>([]);
  const [total, setTotal] = useState(0);
  const [loading, setLoading] = useState(true);
  const [refreshing, setRefreshing] = useState(false);

  /* -- Filter ------------------------------------------------------ */
  const [filterTab, setFilterTab] = useState<FilterValue>("all");

  /* -- Selection (ordered — index = numbering in ZIP) -------------- */
  const [selectedIds, setSelectedIds] = useState<string[]>([]);
  const [downloadingSelection, setDownloadingSelection] = useState(false);

  const toggleSelect = (id: string) => {
    setSelectedIds((prev) =>
      prev.includes(id) ? prev.filter((x) => x !== id) : [...prev, id],
    );
  };

  const handleDownloadSelection = async () => {
    if (selectedIds.length === 0) return;
    setDownloadingSelection(true);
    try {
      // ZIP endpoint only exists on the legacy backend today. For pilot
      // users on the gis-ac path we fall back to triggering individual
      // PDF downloads (one-by-one) until gis-api ships a batch endpoint.
      if (useGisAc) {
        for (const id of selectedIds) {
          const a = document.createElement("a");
          a.href = cfDownloadUrl(true, id);
          a.target = "_blank";
          a.rel = "noopener noreferrer";
          a.click();
        }
      } else {
        const ids = selectedIds.join(",");
        const a = document.createElement("a");
        a.href = `/api/ancpi/download-zip?ids=${encodeURIComponent(ids)}`;
        a.download = `Extrase_CF_selectie_${selectedIds.length}.zip`;
        a.click();
      }
    } finally {
      setTimeout(() => setDownloadingSelection(false), 2000);
    }
  };

  /* -- Search ------------------------------------------------------ */
  const [searchQuery, setSearchQuery] = useState("");

  /* -- SIRUTA autocomplete ----------------------------------------- */
  const [sirutaSearch, setSirutaSearch] = useState("");
  const [sirutaResults, setSirutaResults] = useState<GisUatResult[]>([]);
  const [showSirutaResults, setShowSirutaResults] = useState(false);

  /* -- Downloading all --------------------------------------------- */
  const [downloadingAll, setDownloadingAll] = useState(false);

  /* -- Polling ----------------------------------------------------- */
  const pollRef = useRef<ReturnType<typeof setInterval> | null>(null);
  const hasActive = orders.some((o) => isActiveStatus(o.status));

  /* -- Fetch session status ---------------------------------------- */
  const fetchEpayStatus = useCallback(async () => {
    try {
      const res = await fetch("/api/ancpi/session");
      const data = (await res.json()) as EpaySessionStatus;
      setEpayStatus(data);
    } catch {
      /* silent */
    }
  }, []);

  /* -- Fetch orders ------------------------------------------------ */
  const fetchOrders = useCallback(
    async (showRefreshing = false) => {
      if (showRefreshing) setRefreshing(true);
      try {
        const data = await fetchCfOrdersList(useGisAc, { limit: 200 });
        setOrders(data.orders);
        setTotal(data.total);
      } catch {
        /* silent */
      } finally {
        setLoading(false);
        setRefreshing(false);
      }
    },
    [useGisAc],
  );

  /* -- Initial load ------------------------------------------------ */
  useEffect(() => {
    void fetchEpayStatus();
    void fetchOrders();
  }, [fetchEpayStatus, fetchOrders]);

  /* -- Auto-refresh when active orders exist ----------------------- */
  useEffect(() => {
    if (pollRef.current) clearInterval(pollRef.current);

    if (hasActive) {
      pollRef.current = setInterval(() => {
        void fetchOrders();
        void fetchEpayStatus();
      }, 10_000);
    }

    return () => {
      if (pollRef.current) clearInterval(pollRef.current);
    };
  }, [hasActive, fetchOrders, fetchEpayStatus]);

  /* -- SIRUTA autocomplete ----------------------------------------- */
  useEffect(() => {
    const raw = sirutaSearch.trim();
    if (raw.length < 2) {
      setSirutaResults([]);
      return;
    }
    // Only search if it looks like a SIRUTA code (digits)
    if (!/^\d+$/.test(raw)) {
      setSirutaResults([]);
      return;
    }

    const controller = new AbortController();
    void (async () => {
      try {
        const res = await fetch("/api/eterra/uats", { signal: controller.signal });
        const data = (await res.json()) as { uats?: GisUatResult[] };
        if (data.uats) {
          const matches = data.uats
            .filter((u) => u.siruta.startsWith(raw))
            .slice(0, 8);
          setSirutaResults(matches);
        }
      } catch {
        /* silent */
      }
    })();

    return () => controller.abort();
  }, [sirutaSearch]);

  /* -- Re-order (for expired extracts) ----------------------------- */
  const handleReorder = async (order: CfExtractRecord) => {
    const result = await placeCfOrder(useGisAc, {
      nrCadastral: order.nrCadastral,
      nrCF: order.nrCF,
      siruta: order.siruta,
      judetName: order.judetName,
      uatName: order.uatName,
    });
    if (result.ok) {
      void fetchOrders(true);
      void fetchEpayStatus();
    }
    /* errors surfaced inline via downstream polling later */
  };

  /* -- Download all valid as ZIP ----------------------------------- */
  const handleDownloadAll = async () => {
    const validOrders = filteredOrders.filter(
      (o) => o.status === "completed" && o.minioPath && !isExpired(o.expiresAt),
    );
    if (validOrders.length === 0) return;

    setDownloadingAll(true);
    try {
      if (useGisAc) {
        // No bulk-zip endpoint on api.gis.ac yet — trigger individual
        // PDF downloads. Browser dedup will handle these as separate tabs.
        for (const o of validOrders) {
          const a = document.createElement("a");
          a.href = cfDownloadUrl(true, o.id);
          a.target = "_blank";
          a.rel = "noopener noreferrer";
          a.click();
        }
      } else {
        const ids = validOrders.map((o) => o.id).join(",");
        const res = await fetch(`/api/ancpi/download-zip?ids=${ids}`);
        if (!res.ok) throw new Error("Eroare descarcare ZIP");

        const blob = await res.blob();
        const cd = res.headers.get("Content-Disposition") ?? "";
        const match = /filename="?([^"]+)"?/.exec(cd);
        const filename = match?.[1]
          ? decodeURIComponent(match[1])
          : "Extrase_CF.zip";

        const url = URL.createObjectURL(blob);
        const a = document.createElement("a");
        a.href = url;
        a.download = filename;
        document.body.appendChild(a);
        a.click();
        a.remove();
        URL.revokeObjectURL(url);
      }
    } catch {
      /* silent */
    } finally {
      setDownloadingAll(false);
    }
  };

  /* -- Filter + search orders -------------------------------------- */
  const filteredOrders = orders.filter((order) => {
    // Filter tab
    switch (filterTab) {
      case "valid":
        if (order.status !== "completed" || isExpired(order.expiresAt)) return false;
        break;
      case "expired":
        if (order.status !== "completed" || !isExpired(order.expiresAt)) return false;
        break;
      case "active":
        if (!isActiveStatus(order.status)) return false;
        break;
    }

    // Text search
    const query = searchQuery.trim().toLowerCase();
    if (query) {
      const searchable = [
        order.nrCadastral,
        order.nrCF,
        order.uatName,
        order.judetName,
        order.siruta,
      ]
        .filter(Boolean)
        .join(" ")
        .toLowerCase();
      if (!searchable.includes(query)) return false;
    }

    return true;
  });

  // Count valid extracts for the "Descarca tot" button
  const validCount = filteredOrders.filter(
    (o) => o.status === "completed" && o.minioPath && !isExpired(o.expiresAt),
  ).length;

  /* -- Render ------------------------------------------------------ */
  return (
    <div className="space-y-4">
      {/* -- Header ------------------------------------------------- */}
      <div className="flex items-center justify-between gap-3 flex-wrap">
        <div className="flex items-center gap-3">
          <FileText className="h-5 w-5 text-muted-foreground" />
          <h3 className="text-sm font-semibold">Extrase CF</h3>
          <span className="text-xs text-muted-foreground">
            {total} extras{total !== 1 ? "e" : ""}
          </span>
        </div>
        <div className="flex items-center gap-2">
          {/* Download selection */}
          {selectedIds.length > 0 && (
            <TooltipProvider>
              <Tooltip>
                <TooltipTrigger asChild>
                  <Button
                    variant="default"
                    size="sm"
                    className="h-7 text-xs"
                    disabled={downloadingSelection}
                    onClick={() => void handleDownloadSelection()}
                  >
                    {downloadingSelection ? (
                      <Loader2 className="h-3 w-3 mr-1 animate-spin" />
                    ) : (
                      <Download className="h-3 w-3 mr-1" />
                    )}
                    Descarca selectie ({selectedIds.length})
                  </Button>
                </TooltipTrigger>
                <TooltipContent>
                  ZIP cu {selectedIds.length} extrase numerotate in ordinea selectarii
                </TooltipContent>
              </Tooltip>
            </TooltipProvider>
          )}
          {/* Download all valid */}
          {validCount > 0 && (
            <TooltipProvider>
              <Tooltip>
                <TooltipTrigger asChild>
                  <Button
                    variant="outline"
                    size="sm"
                    className="h-7 text-xs"
                    disabled={downloadingAll}
                    onClick={() => void handleDownloadAll()}
                  >
                    {downloadingAll ? (
                      <Loader2 className="h-3 w-3 mr-1 animate-spin" />
                    ) : (
                      <Archive className="h-3 w-3 mr-1" />
                    )}
                    Descarca tot ({validCount})
                  </Button>
                </TooltipTrigger>
                <TooltipContent>
                  ZIP cu toate extrasele valabile
                </TooltipContent>
              </Tooltip>
            </TooltipProvider>
          )}
          <Button
            variant="ghost"
            size="sm"
            className="h-7 text-xs"
            disabled={refreshing}
            onClick={() => void fetchOrders(true)}
          >
            {refreshing ? (
              <Loader2 className="h-3 w-3 mr-1 animate-spin" />
            ) : (
              <RefreshCw className="h-3 w-3 mr-1" />
            )}
            Reincarca
          </Button>
        </div>
      </div>

      {/* -- Search bar --------------------------------------------- */}
      <div className="flex items-center gap-2">
        <div className="relative flex-1">
          <Search className="absolute left-2.5 top-2 h-3.5 w-3.5 text-muted-foreground pointer-events-none" />
          <Input
            placeholder="Cauta dupa nr. cadastral, UAT, judet..."
            value={searchQuery}
            onChange={(e) => setSearchQuery(e.target.value)}
            className="h-8 pl-8 text-xs"
          />
        </div>
      </div>

      {/* -- Filter tabs -------------------------------------------- */}
      <div className="flex gap-1 p-0.5 bg-muted rounded-md w-fit">
        {FILTER_OPTIONS.map((opt) => (
          <button
            key={opt.value}
            type="button"
            className={cn(
              "px-2.5 py-1 text-xs rounded-sm transition-colors",
              filterTab === opt.value
                ? "bg-background text-foreground shadow-sm font-medium"
                : "text-muted-foreground hover:text-foreground",
            )}
            onClick={() => setFilterTab(opt.value)}
          >
            {opt.label}
            {opt.value === "active" && hasActive && (
              <span className="ml-1 inline-flex h-1.5 w-1.5 rounded-full bg-yellow-500" />
            )}
          </button>
        ))}
      </div>

      {/* -- Orders table ------------------------------------------- */}
      {loading ? (
        <Card>
          <CardContent className="py-12 text-center text-muted-foreground">
            <Loader2 className="h-8 w-8 mx-auto mb-3 animate-spin opacity-40" />
            <p>Se incarca extrasele...</p>
          </CardContent>
        </Card>
      ) : filteredOrders.length === 0 ? (
        <Card>
          <CardContent className="py-12 text-center text-muted-foreground">
            <FileText className="h-10 w-10 mx-auto mb-3 opacity-30" />
            <p className="font-medium">
              {orders.length === 0
                ? "Niciun extras CF"
                : "Niciun rezultat pentru filtrele selectate"}
            </p>
            <p className="text-xs mt-1">
              {orders.length === 0
                ? "Foloseste butonul de pe fiecare parcela din tab-ul Cautare sau Lista mea."
                : "Incearca sa schimbi filtrul sau sa stergi cautarea."}
            </p>
          </CardContent>
        </Card>
      ) : (
        <div className="overflow-x-auto rounded-md border">
          <table className="w-full text-sm">
            <thead>
              <tr className="border-b bg-muted/40">
                <th className="px-3 py-2 text-center font-medium w-8">
                  <TooltipProvider>
                    <Tooltip>
                      <TooltipTrigger asChild>
                        <input
                          type="checkbox"
                          className="rounded cursor-pointer"
                          checked={
                            filteredOrders.length > 0 &&
                            filteredOrders
                              .filter((o) => o.status === "completed" && o.minioPath)
                              .every((o) => selectedIds.includes(o.id))
                          }
                          onChange={() => {
                            const downloadable = filteredOrders.filter(
                              (o) => o.status === "completed" && o.minioPath,
                            );
                            const allSelected = downloadable.every((o) =>
                              selectedIds.includes(o.id),
                            );
                            if (allSelected) {
                              setSelectedIds([]);
                            } else {
                              setSelectedIds(downloadable.map((o) => o.id));
                            }
                          }}
                        />
                      </TooltipTrigger>
                      <TooltipContent>Selecteaza/deselecteaza tot</TooltipContent>
                    </Tooltip>
                  </TooltipProvider>
                </th>
                <th className="px-3 py-2 text-left font-medium w-8">#</th>
                <th className="px-3 py-2 text-left font-medium">
                  Nr. Cadastral
                </th>
                <th className="px-3 py-2 text-left font-medium">UAT</th>
                <th className="px-3 py-2 text-left font-medium">Status</th>
                <th className="px-3 py-2 text-left font-medium">Data</th>
                <th className="px-3 py-2 text-left font-medium">Expira</th>
                <th className="px-3 py-2 text-right font-medium">
                  Actiuni
                </th>
              </tr>
            </thead>
            <tbody>
              {filteredOrders.map((order, idx) => {
                const badge = statusBadge(order.status, order.expiresAt);
                const expired =
                  order.status === "completed" && isExpired(order.expiresAt);

                return (
                  <tr
                    key={order.id}
                    className={cn(
                      "border-b last:border-0 transition-colors hover:bg-muted/30",
                      expired && "opacity-70",
                    )}
                  >
                    {/* Checkbox */}
                    <td className="px-3 py-2 text-center">
                      {order.status === "completed" && order.minioPath ? (
                        <TooltipProvider>
                          <Tooltip>
                            <TooltipTrigger asChild>
                              <input
                                type="checkbox"
                                className="rounded cursor-pointer"
                                checked={selectedIds.includes(order.id)}
                                onChange={() => toggleSelect(order.id)}
                              />
                            </TooltipTrigger>
                            <TooltipContent>
                              {selectedIds.includes(order.id)
                                ? `#${selectedIds.indexOf(order.id) + 1} in ZIP`
                                : "Adauga in selectie"}
                            </TooltipContent>
                          </Tooltip>
                        </TooltipProvider>
                      ) : (
                        <span className="text-muted-foreground/30">—</span>
                      )}
                    </td>
                    {/* # */}
                    <td className="px-3 py-2 text-xs text-muted-foreground tabular-nums">
                      {idx + 1}
                    </td>

                    {/* Nr. Cadastral */}
                    <td className="px-3 py-2">
                      <div className="flex flex-col">
                        <span className="font-medium tabular-nums">
                          {order.nrCadastral}
                        </span>
                        {order.nrCF &&
                          order.nrCF !== order.nrCadastral && (
                            <span className="text-[10px] text-muted-foreground">
                              CF: {order.nrCF}
                            </span>
                          )}
                        {order.version > 1 && (
                          <span className="text-[10px] text-muted-foreground">
                            v{order.version}
                          </span>
                        )}
                      </div>
                    </td>

                    {/* UAT */}
                    <td className="px-3 py-2">
                      <div className="flex flex-col">
                        <span>{order.uatName}</span>
                        <span className="text-[10px] text-muted-foreground">
                          jud. {order.judetName}
                        </span>
                      </div>
                    </td>

                    {/* Status */}
                    <td className="px-3 py-2">
                      <span
                        className={cn(
                          "inline-flex items-center rounded-full border px-2 py-0.5 text-[10px] font-medium",
                          badge.className,
                          badge.pulse && "animate-pulse",
                        )}
                      >
                        {badge.label}
                      </span>
                      {order.errorMessage && (
                        <p
                          className="text-[10px] text-destructive mt-0.5 max-w-48 truncate"
                          title={order.errorMessage}
                        >
                          {order.errorMessage}
                        </p>
                      )}
                    </td>

                    {/* Data */}
                    <td className="px-3 py-2 text-xs text-muted-foreground tabular-nums">
                      {formatDate(order.completedAt ?? order.createdAt)}
                    </td>

                    {/* Expira */}
                    <td className="px-3 py-2 text-xs tabular-nums">
                      {order.expiresAt ? (
                        <span
                          className={cn(
                            expired
                              ? "text-orange-600 dark:text-orange-400"
                              : "text-muted-foreground",
                          )}
                        >
                          {expired && (
                            <Clock className="inline h-3 w-3 mr-0.5 -mt-0.5" />
                          )}
                          {formatShortDate(order.expiresAt)}
                        </span>
                      ) : (
                        <span className="text-muted-foreground">{"—"}</span>
                      )}
                    </td>

                    {/* Actiuni */}
                    <td className="px-3 py-2 text-right">
                      <div className="flex items-center justify-end gap-1">
                        {order.status === "completed" &&
                          order.minioPath &&
                          !expired && (
                            <TooltipProvider>
                              <Tooltip>
                                <TooltipTrigger asChild>
                                  <Button
                                    variant="ghost"
                                    size="sm"
                                    className="h-7 px-2 text-xs"
                                    asChild
                                  >
                                    <a
                                      href={cfDownloadUrl(useGisAc, order.id)}
                                      target="_blank"
                                      rel="noopener noreferrer"
                                    >
                                      <Download className="h-3 w-3 mr-1" />
                                      Descarca
                                    </a>
                                  </Button>
                                </TooltipTrigger>
                                <TooltipContent>
                                  Descarca extras CF ({order.nrCadastral})
                                </TooltipContent>
                              </Tooltip>
                            </TooltipProvider>
                          )}
                        {expired && order.status === "completed" && order.minioPath && (
                          <TooltipProvider>
                            <Tooltip>
                              <TooltipTrigger asChild>
                                <Button
                                  variant="ghost"
                                  size="sm"
                                  className="h-7 px-2 text-xs text-muted-foreground"
                                  asChild
                                >
                                  <a
                                    href={cfDownloadUrl(useGisAc, order.id)}
                                    target="_blank"
                                    rel="noopener noreferrer"
                                  >
                                    <Download className="h-3 w-3 mr-1" />
                                    Descarca
                                  </a>
                                </Button>
                              </TooltipTrigger>
                              <TooltipContent>
                                {`Descarca versiunea expirata (${formatShortDate(order.expiresAt)})`}
                              </TooltipContent>
                            </Tooltip>
                          </TooltipProvider>
                        )}
                        {expired && (
                          <TooltipProvider>
                            <Tooltip>
                              <TooltipTrigger asChild>
                                <Button
                                  variant="default"
                                  size="sm"
                                  className="h-7 px-3 text-xs bg-orange-600 hover:bg-orange-700 text-white"
                                  disabled={!epayStatus.connected}
                                  onClick={() => void handleReorder(order)}
                                >
                                  <RefreshCw className="h-3 w-3 mr-1" />
                                  Actualizeaza
                                </Button>
                              </TooltipTrigger>
                              <TooltipContent>
                                <p>Comanda extras CF nou (1 credit)</p>
                                <p className="text-xs text-muted-foreground">
                                  Extrasul actual a expirat
                                </p>
                              </TooltipContent>
                            </Tooltip>
                          </TooltipProvider>
                        )}
                      </div>
                    </td>
                  </tr>
                );
              })}
            </tbody>
          </table>
        </div>
      )}

      {/* -- Active orders indicator -------------------------------- */}
      {hasActive && (
        <div className="flex items-center gap-2 text-xs text-muted-foreground">
          <Loader2 className="h-3 w-3 animate-spin" />
          <span>
            Se actualizeaza automat la fiecare 10 secunde...
          </span>
        </div>
      )}
    </div>
  );
}
