"use client";

import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
import { api } from "@/lib/api";
import type { Note } from "@/lib/types";
import { format, parseISO } from "date-fns";
import { de } from "date-fns/locale";
import { Plus, Pencil, Trash2, X, Check, MessageSquare } from "lucide-react";
import { useState } from "react";
import { toast } from "sonner";

interface NotesListProps {
  parentType: "case" | "deadline" | "appointment" | "case_event";
  parentId: string;
}

export function NotesList({ parentType, parentId }: NotesListProps) {
  const queryClient = useQueryClient();
  const queryKey = ["notes", parentType, parentId];

  const [newContent, setNewContent] = useState("");
  const [showNew, setShowNew] = useState(false);
  const [editingId, setEditingId] = useState<string | null>(null);
  const [editContent, setEditContent] = useState("");

  const { data: notes, isLoading } = useQuery({
    queryKey,
    queryFn: () =>
      api.get<Note[]>(`/notes?${parentType}_id=${parentId}`),
  });

  const createMutation = useMutation({
    mutationFn: (content: string) => {
      const body: Record<string, string> = {
        content,
        [`${parentType}_id`]: parentId,
      };
      return api.post<Note>("/notes", body);
    },
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey });
      setNewContent("");
      setShowNew(false);
      toast.success("Notiz erstellt");
    },
    onError: () => toast.error("Fehler beim Erstellen der Notiz"),
  });

  const updateMutation = useMutation({
    mutationFn: ({ id, content }: { id: string; content: string }) =>
      api.put<Note>(`/notes/${id}`, { content }),
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey });
      setEditingId(null);
      toast.success("Notiz aktualisiert");
    },
    onError: () => toast.error("Fehler beim Aktualisieren der Notiz"),
  });

  const deleteMutation = useMutation({
    mutationFn: (id: string) => api.delete(`/notes/${id}`),
    onSuccess: () => {
      queryClient.invalidateQueries({ queryKey });
      toast.success("Notiz geloescht");
    },
    onError: () => toast.error("Fehler beim Loeschen der Notiz"),
  });

  function handleCreate() {
    if (!newContent.trim()) return;
    createMutation.mutate(newContent.trim());
  }

  function handleUpdate(id: string) {
    if (!editContent.trim()) return;
    updateMutation.mutate({ id, content: editContent.trim() });
  }

  function startEdit(note: Note) {
    setEditingId(note.id);
    setEditContent(note.content);
  }

  const notesList = Array.isArray(notes) ? notes : [];

  return (
    <div className="rounded-lg border border-neutral-200 bg-white">
      <div className="flex items-center justify-between border-b border-neutral-100 px-4 py-3">
        <h3 className="text-sm font-medium text-neutral-900">Notizen</h3>
        {!showNew && (
          <button
            onClick={() => setShowNew(true)}
            className="flex items-center gap-1 rounded-md px-2 py-1 text-xs text-neutral-500 transition-colors hover:bg-neutral-50 hover:text-neutral-700"
          >
            <Plus className="h-3.5 w-3.5" />
            Neu
          </button>
        )}
      </div>

      {showNew && (
        <div className="border-b border-neutral-100 p-4">
          <textarea
            value={newContent}
            onChange={(e) => setNewContent(e.target.value)}
            rows={3}
            autoFocus
            placeholder="Notiz schreiben..."
            className="w-full rounded-md border border-neutral-200 px-3 py-2 text-sm outline-none focus:border-neutral-400 focus:ring-1 focus:ring-neutral-400"
          />
          <div className="mt-2 flex justify-end gap-2">
            <button
              onClick={() => {
                setShowNew(false);
                setNewContent("");
              }}
              className="rounded-md px-2.5 py-1 text-xs text-neutral-500 hover:bg-neutral-50"
            >
              Abbrechen
            </button>
            <button
              onClick={handleCreate}
              disabled={!newContent.trim() || createMutation.isPending}
              className="rounded-md bg-neutral-900 px-2.5 py-1 text-xs font-medium text-white hover:bg-neutral-800 disabled:opacity-50"
            >
              {createMutation.isPending ? "Speichern..." : "Speichern"}
            </button>
          </div>
        </div>
      )}

      {isLoading ? (
        <div className="space-y-2 p-4">
          {[1, 2].map((i) => (
            <div key={i} className="h-12 animate-pulse rounded-md bg-neutral-100" />
          ))}
        </div>
      ) : notesList.length === 0 ? (
        <div className="flex flex-col items-center py-8 text-center">
          <MessageSquare className="h-5 w-5 text-neutral-300" />
          <p className="mt-2 text-sm text-neutral-400">
            Keine Notizen vorhanden.
          </p>
        </div>
      ) : (
        <div className="divide-y divide-neutral-100">
          {notesList.map((note) => (
            <div key={note.id} className="group px-4 py-3">
              {editingId === note.id ? (
                <div>
                  <textarea
                    value={editContent}
                    onChange={(e) => setEditContent(e.target.value)}
                    rows={3}
                    autoFocus
                    className="w-full rounded-md border border-neutral-200 px-3 py-2 text-sm outline-none focus:border-neutral-400 focus:ring-1 focus:ring-neutral-400"
                  />
                  <div className="mt-2 flex justify-end gap-2">
                    <button
                      onClick={() => setEditingId(null)}
                      className="rounded-md p-1 text-neutral-400 hover:bg-neutral-50 hover:text-neutral-600"
                    >
                      <X className="h-3.5 w-3.5" />
                    </button>
                    <button
                      onClick={() => handleUpdate(note.id)}
                      disabled={!editContent.trim() || updateMutation.isPending}
                      className="rounded-md p-1 text-neutral-400 hover:bg-neutral-50 hover:text-green-600"
                    >
                      <Check className="h-3.5 w-3.5" />
                    </button>
                  </div>
                </div>
              ) : (
                <div>
                  <div className="flex items-start justify-between">
                    <p className="whitespace-pre-wrap text-sm text-neutral-700">
                      {note.content}
                    </p>
                    <div className="ml-4 flex shrink-0 gap-1 opacity-0 transition-opacity group-hover:opacity-100">
                      <button
                        onClick={() => startEdit(note)}
                        className="rounded p-1 text-neutral-400 hover:bg-neutral-50 hover:text-neutral-600"
                      >
                        <Pencil className="h-3 w-3" />
                      </button>
                      <button
                        onClick={() => deleteMutation.mutate(note.id)}
                        className="rounded p-1 text-neutral-400 hover:bg-red-50 hover:text-red-500"
                      >
                        <Trash2 className="h-3 w-3" />
                      </button>
                    </div>
                  </div>
                  <p className="mt-1 text-xs text-neutral-400">
                    {format(parseISO(note.created_at), "d. MMM yyyy, HH:mm", {
                      locale: de,
                    })}
                    {note.updated_at !== note.created_at && " (bearbeitet)"}
                  </p>
                </div>
              )}
            </div>
          ))}
        </div>
      )}
    </div>
  );
}