"use client";

import type { PlaitElement } from "@plait/core";
import {
  ExternalLink,
  FileDown,
  Link2,
  StickyNote,
  Tag,
  X,
} from "lucide-react";
import { useEffect, useRef, useState } from "react";
import {
  getSafeTopicHref,
  getTopicDetails,
  getTopicTitle,
  type TopicDetails,
  type TopicEntry,
} from "@/lib/flow-board/topic-details";

import { getNoteDocument } from "@/lib/flow-board/topic-notes";
import { XmindNotesEditor } from "./xmind-notes-editor";

export type TopicDetailSection = "notes" | "links" | "labels";

export function XmindTopicPanel({
  topic,
  topics,
  section,
  onPatch,
  onJump,
  onClose,
}: {
  topic: PlaitElement | null;
  topics: TopicEntry[];
  section: TopicDetailSection;
  onPatch: (patch: Partial<TopicDetails>) => void;
  onJump: (id: string) => void;
  onClose: () => void;
}) {
  const details = getTopicDetails(topic);
  const [labelDraft, setLabelDraft] = useState("");
  const [linkDraft, setLinkDraft] = useState(details.href);
  const [attachmentError, setAttachmentError] = useState("");
  const [isReadingAttachment, setIsReadingAttachment] = useState(false);
  const attachmentRef = useRef<HTMLInputElement>(null);

  const linkRef = useRef<HTMLInputElement>(null);
  const labelRef = useRef<HTMLInputElement>(null);
  useEffect(() => {
    setLinkDraft(details.href);
  }, [topic?.id, details.href]);
  useEffect(() => {
    setLabelDraft("");
    setAttachmentError("");
  }, [topic?.id]);
  useEffect(() => {
    if (section === "links") linkRef.current?.focus();
    if (section === "labels") labelRef.current?.focus();
  }, [section]);
  const safeHref = getSafeTopicHref(linkDraft);
  const invalidHref = Boolean(linkDraft.trim()) && !safeHref;
  const addLabel = () => {
    const value = labelDraft.trim();
    if (value && !details.labels.includes(value))
      onPatch({ labels: [...details.labels, value] });
    setLabelDraft("");
  };
  const addAttachment = async (file: File) => {
    setAttachmentError("");
    if (file.size > 8 * 1024 * 1024) {
      setAttachmentError("附件不能超过 8 MB。");
      return;
    }
    setIsReadingAttachment(true);
    try {
      const url = await new Promise<string>((resolve, reject) => {
        const reader = new FileReader();
        reader.onerror = () => reject(new Error("读取失败"));
        reader.onload = () => resolve(String(reader.result));
        // Always download attachments as files, independent of their source type.
        reader.readAsDataURL(
          new Blob([file], { type: "application/octet-stream" })
        );
      });
      onPatch({
        attachment: {
          name: file.name,
          url,
          mimeType: "application/octet-stream",
        },
      });
    } catch {
      setAttachmentError("无法读取附件，请重新选择。");
    } finally {
      setIsReadingAttachment(false);
    }
  };
  return (
    <aside
      className="xmind-aux-panel absolute right-0 top-[94px] bottom-9 z-30 w-full max-w-[304px] overflow-y-auto border-l border-[#dfe2e7] bg-white text-[#343b48]"
      data-flow-board-shell-control="true"
    >
      <div className="flex h-12 items-center justify-between border-b border-[#eceef1] px-4">
        <h2 className="text-sm font-semibold">主题内容</h2>
        <button type="button" aria-label="关闭主题内容" onClick={onClose}>
          <X size={16} />
        </button>
      </div>
      {!topic ? (
        <p className="p-4 text-xs text-[#8b919c]">
          选择一个主题，编辑它的备注、链接和标签。
        </p>
      ) : (
        <div className="space-y-6 p-4 text-xs">
          <p className="truncate font-medium" title={getTopicTitle(topic)}>
            {getTopicTitle(topic)}
          </p>
          <section className="space-y-2">
            <h3 className="flex items-center gap-2 font-medium"><StickyNote size={14} />笔记</h3>
            <XmindNotesEditor key={topic.id} value={getNoteDocument(topic)} onChange={(notesDocument) => onPatch({notesDocument})} />
          </section>
          <section className="space-y-2">
            <h3 className="flex items-center gap-2 font-medium">
              <Tag size={14} />
              标签
            </h3>
            <div className="flex flex-wrap gap-1.5">
              {details.labels.map((label) => (
                <span
                  key={label}
                  className="flex items-center gap-1 rounded bg-[#edf3ff] px-2 py-1 text-[#3569e8]"
                >
                  {label}
                  <button
                    type="button"
                    aria-label={`移除标签 ${label}`}
                    onClick={() =>
                      onPatch({
                        labels: details.labels.filter(
                          (value) => value !== label
                        ),
                      })
                    }
                  >
                    <X size={12} />
                  </button>
                </span>
              ))}
            </div>
            <div className="flex gap-2">
              <input
                aria-label="新增主题标签"
                ref={labelRef}
                className="h-8 min-w-0 flex-1 rounded border border-[#dfe2e7] px-2"
                placeholder="输入标签后回车"
                value={labelDraft}
                onChange={(event) => setLabelDraft(event.target.value)}
                onKeyDown={(event) => {
                  if (event.key === "Enter" && !event.nativeEvent.isComposing) {
                    event.preventDefault();
                    addLabel();
                  }
                }}
              />
              <button
                type="button"
                className="rounded border border-[#dfe2e7] px-2"
                onClick={addLabel}
              >
                添加
              </button>
            </div>
          </section>
          <section className="space-y-2">
            <h3 className="flex items-center gap-2 font-medium">
              <Link2 size={14} />
              网页或邮件链接
            </h3>
            <input
              aria-label="主题外部链接"
              ref={linkRef}
              aria-invalid={invalidHref}
              className="h-8 w-full rounded border border-[#dfe2e7] px-2"
              placeholder="https://…"
              value={linkDraft}
              onChange={(event) => setLinkDraft(event.target.value)}
              onBlur={() => {
                if (!invalidHref) onPatch({ href: linkDraft.trim() });
              }}
              onKeyDown={(event) => {
                if (event.key === "Enter" && !invalidHref) {
                  event.preventDefault();
                  onPatch({ href: linkDraft.trim() });
                }
              }}
            />
            {invalidHref ? (
              <p role="alert" className="text-red-600">
                请输入完整的 http、https、mailto 或 tel 链接。
              </p>
            ) : safeHref ? (
              <a
                className="inline-flex items-center gap-1 text-[#3569e8]"
                href={safeHref}
                rel="noopener noreferrer"
                target="_blank"
              >
                <ExternalLink size={12} />
                打开链接
              </a>
            ) : null}
            {details.href ? (
              <button
                type="button"
                className="ml-3 text-[#8b919c]"
                onClick={() => {
                  setLinkDraft("");
                  onPatch({ href: "" });
                }}
              >
                移除外部链接
              </button>
            ) : null}
          </section>
          <section className="space-y-2">
            <h3 className="flex items-center gap-2 font-medium">
              <FileDown size={14} />
              附件
            </h3>
            {details.attachment ? (
              <>
                <a
                  className="block break-all text-[#3569e8]"
                  href={details.attachment.url}
                  download={details.attachment.name}
                >
                  下载 {details.attachment.name}
                </a>
                <button
                  type="button"
                  className="text-[#8b919c]"
                  onClick={() => onPatch({ attachment: null })}
                >
                  移除附件
                </button>
              </>
            ) : null}
            <input
              ref={attachmentRef}
              type="file"
              className="hidden"
              aria-label="上传主题附件"
              onChange={(event) => {
                const file = event.target.files?.[0];
                event.target.value = "";
                if (file) void addAttachment(file);
              }}
            />
            <button
              type="button"
              className="block text-[#3569e8] disabled:text-gray-400"
              disabled={isReadingAttachment}
              onClick={() => attachmentRef.current?.click()}
            >
              {isReadingAttachment
                ? "正在读取附件…"
                : details.attachment
                  ? "替换附件"
                  : "添加附件"}
            </button>
            {attachmentError ? (
              <p role="alert" className="text-red-600">
                {attachmentError}
              </p>
            ) : null}
          </section>
          <label className="block space-y-2">
            <span className="font-medium">链接到当前画布的主题</span>
            <select
              aria-label="主题链接目标"
              className="h-8 w-full rounded border border-[#dfe2e7] px-2"
              value={details.topicLinkId}
              onChange={(event) => onPatch({ topicLinkId: event.target.value })}
            >
              <option value="">无主题链接</option>
              {details.topicLinkId &&
              !topics.some(
                ({ element }) => element.id === details.topicLinkId
              ) ? (
                <option value={details.topicLinkId}>目标主题已不存在</option>
              ) : null}
              {topics
                .filter(({ element }) => element.id !== topic.id)
                .map(({ element, title, depth }) => (
                  <option key={element.id} value={element.id}>
                    {"　".repeat(Math.min(depth, 5))}
                    {title}
                  </option>
                ))}
            </select>
          </label>
          {details.topicLinkId ? (
            <button
              type="button"
              disabled={
                !topics.some(
                  ({ element }) => element.id === details.topicLinkId
                )
              }
              className="text-[#3569e8] disabled:text-gray-400"
              onClick={() => onJump(details.topicLinkId)}
            >
              定位目标主题
            </button>
          ) : null}
        </div>
      )}
    </aside>
  );
}