"use client";

import { useEffect, useState } from "react";
import { useParams, useRouter } from "next/navigation";
import { ArrowLeft, FileDown, Loader2, Plus, Trash2 } from "lucide-react";
import { AppHeader } from "@/components/layout/app-header";
import { PageHeader } from "@/components/layout/page-header";
import { AssociateFormDialog } from "@/components/associations/associate-form-dialog";
import { AssociateTable } from "@/components/associations/associate-table";
import { AssociationInfoCard } from "@/components/associations/association-info-card";
import { EditAssociationDialog } from "@/components/associations/edit-association-dialog";
import { UserAccountsCard } from "@/components/associations/user-accounts-card";
import { UserFormDialog } from "@/components/associations/user-form-dialog";
import { Button } from "@/components/ui/button";
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
import { ConfirmDialog } from "@/components/ui/confirm-dialog";
import { deleteAssociation, downloadAttestato, getAssociation, updateAssociation } from "@/lib/api";
import type { Associate, Association, User } from "@/lib/models";

export default function AssociationDetailPage() {
  const router = useRouter();
  const params = useParams();
  const id = params.id as string;

  const [association, setAssociation] = useState<Association | null>(null);
  const [loading, setLoading] = useState(true);

  const [associateDialogOpen, setAssociateDialogOpen] = useState(false);
  const [editingAssociateIndex, setEditingAssociateIndex] = useState<number | undefined>(undefined);

  const [userDialogOpen, setUserDialogOpen] = useState(false);
  const [editingUserIndex, setEditingUserIndex] = useState<number | undefined>(undefined);

  const [generatingAttestato, setGeneratingAttestato] = useState(false);

  useEffect(() => {
    getAssociation(id)
      .then(setAssociation)
      .catch((error) => {
        console.error("Failed to load association:", error);
        router.push("/dashboard");
      })
      .finally(() => setLoading(false));
  }, [id, router]);

  const persist = async (updated: Association) => {
    const saved = await updateAssociation(id, updated);
    setAssociation(saved);
  };

  const openAddAssociate = () => {
    setEditingAssociateIndex(undefined);
    setAssociateDialogOpen(true);
  };

  const openEditAssociate = (index: number) => {
    setEditingAssociateIndex(index);
    setAssociateDialogOpen(true);
  };

  const handleAssociateSubmit = async (associate: Associate) => {
    if (!association) return;
    const associates = [...(association.associates ?? [])];
    if (editingAssociateIndex !== undefined) {
      associates[editingAssociateIndex] = associate;
    } else {
      associates.push(associate);
    }
    await persist({ ...association, associates });
  };

  const handleAssociateDelete = async (index: number) => {
    if (!association) return;
    const associates = (association.associates ?? []).filter((_, i) => i !== index);
    await persist({ ...association, associates });
  };

  const openAddUser = () => {
    setEditingUserIndex(undefined);
    setUserDialogOpen(true);
  };

  const openEditUser = (index: number) => {
    setEditingUserIndex(index);
    setUserDialogOpen(true);
  };

  const handleUserSubmit = async (user: User) => {
    if (!association) return;
    const users = [...(association.users ?? [])];
    if (editingUserIndex !== undefined) {
      const existing = users[editingUserIndex];
      users[editingUserIndex] = { ...user, password: user.password || existing.password };
    } else {
      users.push(user);
    }
    await persist({ ...association, users });
  };

  const handleUserDelete = async (index: number) => {
    if (!association) return;
    const users = (association.users ?? []).filter((_, i) => i !== index);
    await persist({ ...association, users });
  };

  const handleDeleteAssociation = async () => {
    await deleteAssociation(id);
    router.push("/dashboard");
  };

  const handleDownloadAttestato = async () => {
    if (!association) return;
    setGeneratingAttestato(true);
    try {
      await downloadAttestato(id, association.name);
    } catch (error) {
      console.error("Failed to generate attestato:", error);
    } finally {
      setGeneratingAttestato(false);
    }
  };

  if (loading) {
    return (
      <div className="flex min-h-screen items-center justify-center text-muted-foreground">
        <Loader2 className="size-5 animate-spin" />
      </div>
    );
  }

  if (!association) {
    return null;
  }

  return (
    <div className="min-h-screen bg-muted/30">
      <AppHeader />
      <main className="mx-auto max-w-5xl space-y-6 p-6">
        <div>
          <Button
            variant="ghost"
            size="sm"
            className="-ml-2 mb-2"
            onClick={() => router.push("/dashboard")}
          >
            <ArrowLeft className="size-4" />
            Torna alle associazioni
          </Button>
          <PageHeader
            title={association.nasFolderNumber != null ? `#${association.nasFolderNumber} ${association.name}` : association.name}
            description={`${association.associates?.length ?? 0} soci registrati`}
            actions={
              <>
                <Button variant="outline" onClick={handleDownloadAttestato} disabled={generatingAttestato}>
                  {generatingAttestato ? (
                    <Loader2 className="size-4 animate-spin" />
                  ) : (
                    <FileDown className="size-4" />
                  )}
                  Genera Certificato di Adesione
                </Button>
                <EditAssociationDialog association={association} onSaved={setAssociation} />
                <ConfirmDialog
                  trigger={
                    <Button variant="outline" className="text-destructive hover:text-destructive">
                      <Trash2 className="size-4" />
                      Elimina
                    </Button>
                  }
                  title="Eliminare questa associazione?"
                  description={`"${association.name}" e tutti i suoi soci verranno eliminati definitivamente. L'operazione non è reversibile.`}
                  confirmLabel="Elimina definitivamente"
                  onConfirm={handleDeleteAssociation}
                />
              </>
            }
          />
        </div>

        <AssociationInfoCard association={association} />

        <Card>
          <CardHeader className="flex flex-row items-center justify-between">
            <CardTitle>Soci ({association.associates?.length ?? 0})</CardTitle>
            <Button size="sm" onClick={openAddAssociate}>
              <Plus className="size-4" />
              Aggiungi socio
            </Button>
          </CardHeader>
          <CardContent>
            <AssociateTable
              associates={association.associates ?? []}
              onEdit={openEditAssociate}
              onDelete={handleAssociateDelete}
            />
          </CardContent>
        </Card>

        <UserAccountsCard
          users={association.users ?? []}
          onEdit={openEditUser}
          onDelete={handleUserDelete}
          actions={
            <Button size="sm" onClick={openAddUser}>
              <Plus className="size-4" />
              Aggiungi account
            </Button>
          }
        />
      </main>

      <AssociateFormDialog
        open={associateDialogOpen}
        onOpenChange={setAssociateDialogOpen}
        initialValue={editingAssociateIndex !== undefined ? association.associates?.[editingAssociateIndex] : undefined}
        onSubmit={handleAssociateSubmit}
      />

      <UserFormDialog
        open={userDialogOpen}
        onOpenChange={setUserDialogOpen}
        initialValue={editingUserIndex !== undefined ? association.users?.[editingUserIndex] : undefined}
        onSubmit={handleUserSubmit}
      />
    </div>
  );
}