import { createSignal, For, Show, onMount } from "solid-js";
import CommentLock from "./CommentLock";
import CommentForm from "./CommentForm";
import type { CommentWithReplies, CommentRecord } from "../../../types/comments";

interface ToastMessage {
  type: "success" | "error";
  message: string;
}

interface CommentsProps {
  postSlug: string;
}

export default function Comments(props: CommentsProps) {
  const [isAuthenticated, setIsAuthenticated] = createSignal(false);
  const [currentUser, setCurrentUser] = createSignal<{
    id: string;
    name: string;
    email: string;
    avatar?: string;
  } | undefined>(undefined);
  const [isLoading, setIsLoading] = createSignal(true);
  const [comments, setComments] = createSignal<CommentWithReplies[]>([]);
  const [replyTo, setReplyTo] = createSignal<string | null>(null);
  const [editingComment, setEditingComment] = createSignal<string | null>(null);
  const [editContent, setEditContent] = createSignal("");
  const [toast, setToast] = createSignal<ToastMessage | null>(null);

  const showToast = (message: ToastMessage): void => {
    setToast(message);
    setTimeout(() => setToast(null), 3000);
  };

  onMount(async () => {
    try {
      const response = await fetch("/api/auth/me", {
        method: "GET",
        credentials: "include",
      });

      const data = await response.json();

      if (data.authenticated && data.user) {
        setIsAuthenticated(true);
        setCurrentUser({
          id: data.user.id,
          name: data.user.name || "Пользователь",
          email: data.user.email,
          avatar: data.user.avatar,
        });
      }
    } catch (error) {
      console.error("[Comments] Ошибка проверки авторизации:", error);
    } finally {
      setIsLoading(false);
    }
  });

  const loadComments = async () => {
    try {
      const response = await fetch(
        `/api/comments?post_slug=${encodeURIComponent(props.postSlug)}&parent=null`,
        {
          method: "GET",
          credentials: "include",
        }
      );

      if (!response.ok) {
        throw new Error("Failed to fetch comments");
      }

      const data = await response.json();

      const commentsWithReplies: CommentWithReplies[] = await Promise.all(
        data.items.map(async (comment: CommentRecord) => {
          const repliesResponse = await fetch(
            `/api/comments?post_slug=${encodeURIComponent(props.postSlug)}&parent=${comment.id}`,
            {
              method: "GET",
              credentials: "include",
            }
          );
          const repliesData = await repliesResponse.json();
          return {
            ...comment,
            replies: repliesData.items || [],
          };
        })
      );

      setComments(commentsWithReplies);
    } catch (error) {
      console.error("[Comments] Ошибка загрузки комментариев:", error);
    }
  };

  onMount(() => {
    if (props.postSlug) {
      loadComments();
    }
  });

  const handleNewComment = async (data: { content: string }) => {
    try {
      const response = await fetch("/api/comments", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        credentials: "include",
        body: JSON.stringify({
          content: data.content,
          post_slug: props.postSlug,
          parent: null,
        }),
      });

      if (!response.ok) {
        const errorData = await response.json();
        throw new Error(errorData.error || "Failed to create comment");
      }

      await loadComments();
    } catch (error) {
      console.error("[Comments] Ошибка создания комментария:", error);
      showToast({ type: "error", message: "Не удалось отправить комментарий" });
    }
  };

  const handleReply = async (commentId: string, data: { content: string }) => {
    try {
      const response = await fetch("/api/comments", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        credentials: "include",
        body: JSON.stringify({
          content: data.content,
          post_slug: props.postSlug,
          parent: commentId,
        }),
      });

      if (!response.ok) {
        const errorData = await response.json();
        if (errorData.error) {
          showToast({ type: "error", message: errorData.error });
          return;
        }
        throw new Error(errorData.error || "Failed to create reply");
      }

      showToast({ type: "success", message: "Ответ успешно отправлен!" });
      await loadComments();
      setReplyTo(null);
    } catch (error) {
      console.error("[Comments] Ошибка создания ответа:", error);
      showToast({ type: "error", message: "Не удалось создать ответ. Попробуйте позже." });
    }
  };

  const handleEdit = async (commentId: string, data: { content: string }) => {
    try {
      const response = await fetch(`/api/comments/${commentId}`, {
        method: "PATCH",
        headers: { "Content-Type": "application/json" },
        credentials: "include",
        body: JSON.stringify({
          content: data.content,
        }),
      });

      if (!response.ok) {
        const errorData = await response.json();
        throw new Error(errorData.error || "Failed to update comment");
      }

      showToast({ type: "success", message: "Комментарий обновлен!" });
      await loadComments();
      setEditingComment(null);
      setEditContent("");
    } catch (error) {
      console.error("[Comments] Ошибка обновления комментария:", error);
      showToast({ type: "error", message: "Не удалось обновить комментарий" });
    }
  };

  const handleDelete = async (commentId: string) => {
    try {
      const response = await fetch(`/api/comments/${commentId}`, {
        method: "DELETE",
        credentials: "include",
      });

      if (!response.ok) {
        const errorData = await response.json();
        throw new Error(errorData.error || "Failed to delete comment");
      }

      showToast({ type: "success", message: "Комментарий удален!" });
      await loadComments();
      setEditingComment(null);
    } catch (error) {
      console.error("[Comments] Ошибка удаления комментария:", error);
      showToast({ type: "error", message: "Не удалось удалить комментарий" });
    }
  };

  const handleReplyClick = (commentId: string) => {
    const currentUserId = currentUser()?.id;
    const comment = comments().find(c => c.id === commentId);
    const commentUserId = comment?.user;

    if (commentUserId && currentUserId === commentUserId) {
      showToast({ type: "error", message: "Нельзя ответить на свой комментарий" });
      return;
    }

    setReplyTo(replyTo() === commentId ? null : commentId);
  };

  const handleEditClick = (commentId: string, content: string) => {
    setEditingComment(commentId);
    setEditContent(content);
  };

  const Avatar = (props: {
    author: string;
    avatar?: string;
    size?: "sm" | "md";
  }) => {
    const size = props.size || "md";
    const sizeClasses = { sm: "w-8 h-8 text-sm", md: "w-12 h-12 text-lg" };

    return (
      <Show
        when={props.avatar}
        fallback={
          <div
            class={`${sizeClasses[size]} rounded-full bg-gradient-to-br from-yellow-400 to-yellow-600 flex items-center justify-center text-white font-bold shrink-0`}
          >
            {props.author.charAt(0)}
          </div>
        }
      >
        <img
          src={props.avatar}
          alt={props.author}
          class={`${sizeClasses[size]} rounded-full object-cover shrink-0`}
        />
      </Show>
    );
  };

  const formatDate = (dateString: string) => {
    const date = new Date(dateString);
    return date.toLocaleDateString("ru-RU", {
      day: "numeric",
      month: "long",
      year: "numeric",
      hour: "2-digit",
      minute: "2-digit",
    });
  };

  const isCommentOwner = (commentUserId?: string) => {
    return currentUser()?.id === commentUserId;
  };

  return (
    <>
      <style>{`
        @media (max-width: 768px) {
          .comments-wrapper { padding: 0 0.75rem; }
          .comments-wrapper h3 { font-size: 1.5rem !important; }
          .comment-card { padding: 1rem !important; }
          .comment-avatar { width: 40px !important; height: 40px !important; }
          .reply-form { margin-left: 0 !important; padding-left: 1rem !important; }
        }
      `}</style>
      <Show when={toast()}>
        {(t) => (
          <div
            class={`fixed bottom-4 right-4 px-6 py-3 rounded-xl shadow-lg transition-all duration-300 z-50 ${
              t().type === "success"
                ? "bg-green-500 text-white"
                : "bg-red-500 text-white"
            }`}
          >
            {t().message}
          </div>
        )}
      </Show>

      {isLoading() ? (
        <div class="max-w-4xl mx-auto mt-12 pt-8 border-t border-gray-200">
          <div class="flex items-center gap-3 mb-8">
            <h3 class="text-2xl font-bold text-gray-900">Комментарии</h3>
            <span class="px-3 py-1 bg-blue-100 text-blue-700 text-sm font-medium rounded-full">
              0
            </span>
          </div>
          <div class="text-center py-12">
            <div class="inline-block animate-spin rounded-full h-12 w-12 border-4 border-blue-600 border-t-transparent"></div>
            <p class="mt-4 text-gray-600">Загрузка...</p>
          </div>
        </div>
      ) : (
        <Show when={isAuthenticated()} fallback={<CommentLock />}>
          <div class="max-w-4xl mx-auto mt-12 pt-8 border-t border-gray-200">
            <div class="flex items-center gap-3 mb-8">
              <h3 class="text-2xl font-bold text-gray-900">Комментарии</h3>
              <span class="px-3 py-1 bg-blue-100 text-blue-700 text-sm font-medium rounded-full">
                {comments().length}
              </span>
            </div>

            <Show
              when={comments().length > 0}
              fallback={
                <div class="text-center py-12 text-gray-500">
                  <p>Пока нет комментариев. Будьте первым!</p>
                </div>
              }
            >
              <div class="space-y-6 mb-10">
                <For each={comments()}>
                  {(comment) => (
                    <div class="bg-white rounded-2xl p-6 shadow-sm border border-gray-100">
                      <div class="flex items-start gap-4">
                        <Avatar
                          author={comment.expand?.user?.firstName || comment.expand?.user?.name || "Аноним"}
                          avatar={comment.expand?.user?.avatar}
                        />
                        <div class="flex-1 min-w-0">
                          <div class="flex items-center gap-2 mb-2 flex-wrap">
                            <span class="font-semibold text-gray-900">
                              {comment.expand?.user?.firstName || comment.expand?.user?.name || "Аноним"}
                            </span>
                            <Show when={comment.is_verified}>
                              <svg
                                class="w-4 h-4 text-blue-600"
                                fill="currentColor"
                                viewBox="0 0 20 20"
                              >
                                <path
                                  fill-rule="evenodd"
                                  d="M10 18a8 8 0 100-16 8 8 0 000 16zm3.707-9.293a1 1 0 00-1.414-1.414L9 10.586 7.707 9.293a1 1 0 00-1.414 1.414l2 2a1 1 0 001.414 0l4-4z"
                                  clip-rule="evenodd"
                                />
                              </svg>
                            </Show>
                            <span class="text-sm text-gray-400 ml-auto">
                              {formatDate(comment.created)}
                            </span>
                          </div>
                          <Show
                            when={editingComment() === comment.id}
                            fallback={
                              <p class="text-gray-700 leading-relaxed mb-3">
                                {comment.content}
                              </p>
                            }
                          >
                            <CommentForm
                              isEdit={true}
                              initialContent={editContent()}
                              onSubmit={(data) => handleEdit(comment.id, data)}
                              onCancel={() => {
                                setEditingComment(null);
                                setEditContent("");
                              }}
                              onDelete={() => handleDelete(comment.id)}
                              user={currentUser()}
                            />
                          </Show>
                          <div class="flex items-center gap-1 flex-wrap">
                            <button
                              onClick={() => handleReplyClick(comment.id)}
                              class="text-sm text-blue-600 hover:text-blue-600-dark font-medium flex items-center gap-1 transition-colors hover:cursor-pointer"
                            >
                              <svg
                                class="w-4 h-4"
                                fill="none"
                                stroke="currentColor"
                                viewBox="0 0 24 24"
                              >
                                <path
                                  stroke-linecap="round"
                                  stroke-linejoin="round"
                                  stroke-width="2"
                                  d="M3 10h10a8 8 0 018 8v2M3 10l6 6m-6-6l6-6"
                                />
                              </svg>
                              {replyTo() === comment.id ? "Отменить" : "Ответить"}
                            </button>
                            <Show when={isCommentOwner(comment.user)}>
                              <button
                                onClick={() => handleEditClick(comment.id, comment.content)}
                                class="text-sm text-gray-400 hover:text-blue-600 font-medium flex items-center gap-1 transition-colors hover:cursor-pointer ml-2"
                              >
                                <svg
                                  class="w-4 h-4"
                                  fill="none"
                                  stroke="currentColor"
                                  viewBox="0 0 24 24"
                                >
                                  <path
                                    stroke-linecap="round"
                                    stroke-linejoin="round"
                                    stroke-width="2"
                                    d="M11 5H6a2 2 0 00-2 2v11a2 2 0 002 2h11a2 2 0 002-2v-5m-1.414-9.414a2 2 0 112.828 2.828L11.828 15H9v-2.828l8.586-8.586z"
                                  />
                                </svg>
                                Редактировать
                              </button>
                              <button
                                onClick={() => handleDelete(comment.id)}
                                class="text-sm text-gray-400 hover:text-red-500 font-medium flex items-center gap-1 transition-colors hover:cursor-pointer ml-2"
                              >
                                <svg
                                  class="w-4 h-4"
                                  fill="none"
                                  stroke="currentColor"
                                  viewBox="0 0 24 24"
                                >
                                  <path
                                    stroke-linecap="round"
                                    stroke-linejoin="round"
                                    stroke-width="2"
                                    d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16"
                                  />
                                </svg>
                                Удалить
                              </button>
                            </Show>
                          </div>
                        </div>
                      </div>

                      <Show when={replyTo() === comment.id}>
                        <div class="mt-4 ml-16 pl-4 border-l-2 border-blue-200">
                          <CommentForm
                            isReply={true}
                            onSubmit={(data) => handleReply(comment.id, data)}
                            onCancel={() => setReplyTo(null)}
                            user={currentUser()}
                          />
                        </div>
                      </Show>

                      <Show when={comment.replies && comment.replies.length > 0}>
                        <div class="mt-4 ml-16 space-y-4">
                          <For each={comment.replies}>
                            {(reply) => (
                              <div class="flex items-start gap-3 pl-4 border-l-2 border-gray-200">
                                <Avatar
                                  author={reply.expand?.user?.firstName || reply.expand?.user?.name || "Аноним"}
                                  avatar={reply.expand?.user?.avatar}
                                  size="sm"
                                />
                                <div class="flex-1 bg-gray-50 rounded-xl p-4">
                                  <div class="flex items-center gap-2 mb-1 flex-wrap">
                                    <span class="font-semibold text-gray-900 text-sm">
                                      {reply.expand?.user?.firstName || reply.expand?.user?.name || "Аноним"}
                                    </span>
                                    <Show when={reply.is_verified}>
                                      <svg
                                        class="w-3 h-3 text-blue-600"
                                        fill="currentColor"
                                        viewBox="0 0 20 20"
                                      >
                                        <path
                                          fill-rule="evenodd"
                                          d="M10 18a8 8 0 100-16 8 8 0 000 16zm3.707-9.293a1 1 0 00-1.414-1.414L9 10.586 7.707 9.293a1 1 0 00-1.414 1.414l2 2a1 1 0 001.414 0l4-4z"
                                          clip-rule="evenodd"
                                        />
                                      </svg>
                                    </Show>
                                    <span class="text-xs text-gray-400 ml-auto">
                                      {formatDate(reply.created)}
                                    </span>
                                  </div>
                                  <p class="text-gray-700 text-sm leading-relaxed">
                                    {reply.content}
                                  </p>
                                </div>
                              </div>
                            )}
                          </For>
                        </div>
                      </Show>
                    </div>
                  )}
                </For>
              </div>
            </Show>

            <CommentForm onSubmit={handleNewComment} user={currentUser()} />
          </div>
        </Show>
      )}
    </>
  );
}