import { useEffect } from 'react';
import { useContactStore } from '../stores/contactStore';
import { useSessionStore } from '../stores/sessionStore';
import { useUIStore } from '../stores/uiStore';
import { useMailStore } from '../stores/mailStore';
import type { Contact } from '../types';
import {
  ArchiveIcon,
  ComposeIcon,
  CheckIcon,
  CloseIcon,
  ChevronRightIcon,
  ListViewIcon,
  CardViewIcon
} from './icons';
import { WorkCard } from './WorkCard';

/**
 * 左侧联系人面板：列出所有 name@path.session，支持
 *  - 点击进入该会话
 *  - 写信（预填收件人为该三维地址）
 *  - 归档（Agent 侧会话归档 + 邮箱界面移除）
 */
export default function ContactPanel() {
  const contacts = useContactStore(s => s.contacts);
  const archivedContacts = useContactStore(s => s.archivedContacts);
  const showArchived = useContactStore(s => s.showArchived);
  const loading = useContactStore(s => s.loading);
  const error = useContactStore(s => s.error);
  const pendingArchive = useContactStore(s => s.pendingArchive);
  const fetchContacts = useContactStore(s => s.fetchContacts);
  const toggleArchivedView = useContactStore(s => s.toggleArchivedView);
  const requestArchive = useContactStore(s => s.requestArchive);
  const cancelArchive = useContactStore(s => s.cancelArchive);
  const archive = useContactStore(s => s.archive);
  const view = useContactStore(s => s.view);
  const setView = useContactStore(s => s.setView);

  const selectSession = useSessionStore(s => s.selectSession);
  const currentSession = useSessionStore(s => s.currentSession);
  const clearCurrentMail = useMailStore(s => s.clearCurrentMail);
  const startCompose = useUIStore(s => s.startCompose);
  const cancelCompose = useUIStore(s => s.cancelCompose);
  const showDetail = useUIStore(s => s.showDetail);

  useEffect(() => {
    fetchContacts();
  }, []);

  const open = (c: Contact) => {
    cancelCompose();
    clearCurrentMail();
    selectSession(c.session_id);
    showDetail(); // 窄屏下切到会话内容栏
  };

  return (
    <div
      className={`w-full shrink-0 border-r border-gray-200 bg-white flex flex-col min-w-0 ${
        // 卡片要放两行摘要 + 预算条，320px 会挤；列表视图保持紧凑
        view === 'card' ? 'lg:w-[400px]' : 'lg:w-[320px]'
      }`}
    >
      <div className="px-4 py-3 border-b border-gray-200 flex items-center gap-1">
        <h2 className="text-sm font-semibold text-gray-800">
          {view === 'card' ? '工作列表' : '联系人'}
        </h2>
        <span className="ml-2 text-xs text-gray-400">{contacts.length}</span>
        <div className="flex-1" />
        {/* 视图切换：列表答「跟谁在聊」，卡片答「在聊什么、进展如何」 */}
        <button
          onClick={() => setView(view === 'list' ? 'card' : 'list')}
          title={view === 'list' ? '切换到卡片视图' : '切换到列表视图'}
          className="tap p-1 rounded text-gray-400 hover:text-gray-700 hover:bg-gray-100"
        >
          {view === 'list' ? (
            <CardViewIcon className="w-3.5 h-3.5" />
          ) : (
            <ListViewIcon className="w-3.5 h-3.5" />
          )}
        </button>
        <button
          onClick={toggleArchivedView}
          className={`tap text-2xs px-1.5 py-0.5 rounded ${
            showArchived ? 'bg-blue-600 text-white' : 'text-gray-500 hover:text-gray-800'
          }`}
        >
          归档
        </button>
      </div>

      {error && <p className="px-4 py-2 text-xs text-red-600">{error}</p>}

      <div className="flex-1 overflow-y-auto p-2 space-y-1">
        {loading && contacts.length === 0 && (
          <p className="text-xs text-gray-400 text-center py-6">加载中</p>
        )}

        {contacts.map(c =>
          // 归档确认态两种视图共用同一个确认框：那是个破坏性操作，
          // 换个视图就换套确认 UI 只会让人对「点了什么」更没底
          pendingArchive === c.address ? (
            <ArchiveConfirm
              key={c.session_id}
              contact={c}
              onCancel={cancelArchive}
              onConfirm={() => archive(c)}
            />
          ) : view === 'card' ? (
            <WorkCard
              key={c.session_id}
              contact={c}
              active={currentSession?.session_id === c.session_id}
              onOpen={() => open(c)}
              onCompose={() => startCompose({ to: c.address })}
              onArchive={() => requestArchive(c.address)}
            />
          ) : (
            <ContactRow
              key={c.session_id}
              contact={c}
              active={currentSession?.session_id === c.session_id}
              onOpen={() => open(c)}
              onCompose={() => startCompose({ to: c.address })}
              onRequestArchive={() => requestArchive(c.address)}
            />
          )
        )}

        {!loading && contacts.length === 0 && (
          <p className="text-xs text-gray-400 text-center py-6">
            {view === 'card'
              ? '暂无进行中的工作，发一封邮件即可开始'
              : '暂无联系人，发一封邮件即可建立'}
          </p>
        )}

        {showArchived && (
          <div className="pt-3 mt-2 border-t border-gray-200">
            <p className="px-2 pb-1 text-2xs font-medium text-gray-400">
              已归档 {archivedContacts.length}
            </p>
            {archivedContacts.map(c => (
              <div
                key={c.session_id}
                className="px-3 py-2 rounded-lg opacity-60 hover:opacity-100 hover:bg-gray-50"
              >
                <p className="text-xs font-mono text-gray-500 truncate">{c.address}</p>
                <p className="text-3xs text-gray-500 mt-0.5">
                  {c.mail_count} 封 · 已归档
                </p>
              </div>
            ))}
            {archivedContacts.length === 0 && (
              <p className="text-xs text-gray-400 text-center py-3">无归档会话</p>
            )}
          </div>
        )}
      </div>
    </div>
  );
}

/**
 * 归档确认框。
 *
 * 列表视图与卡片视图共用：归档是破坏性操作，换个视图就换套确认 UI
 * 只会让人对「自己点了什么」更没底。
 */
function ArchiveConfirm({
  contact,
  onCancel,
  onConfirm
}: {
  contact: Contact;
  onCancel: () => void;
  onConfirm: () => void;
}) {
  return (
    <div className="px-3 py-2.5 rounded-lg border border-red-200 bg-red-50">
      <p className="text-xs text-gray-800">
        归档 <span className="font-mono">{contact.address}</span>？
      </p>
      <p className="text-3xs text-gray-500 mt-0.5">
        对应 Agent 的 session 将被归档，此列表与邮箱界面同时移除
      </p>
      <div className="flex gap-2 mt-2">
        <button
          onClick={onConfirm}
          className="tap inline-flex items-center gap-1 px-2.5 py-1 rounded-md bg-red-600 text-white text-2xs font-medium hover:bg-red-700"
        >
          <CheckIcon className="w-3 h-3" />
          确认归档
        </button>
        <button
          onClick={onCancel}
          className="tap inline-flex items-center gap-1 px-2.5 py-1 rounded-md border border-gray-300 text-gray-600 text-2xs hover:bg-white"
        >
          <CloseIcon className="w-3 h-3" />
          取消
        </button>
      </div>
    </div>
  );
}

function ContactRow({
  contact,
  active,
  onOpen,
  onCompose,
  onRequestArchive
}: {
  contact: Contact;
  active: boolean;
  onOpen: () => void;
  onCompose: () => void;
  onRequestArchive: () => void;
}) {
  const time = new Date(contact.last_activity).toLocaleString('zh-CN', {
    month: '2-digit',
    day: '2-digit',
    hour: '2-digit',
    minute: '2-digit'
  });

  return (
    <div
      className={`group px-3 py-2.5 rounded-lg border transition-colors ${
        active ? 'bg-blue-50 border-blue-200' : 'border-transparent hover:bg-gray-50'
      }`}
    >
      <button onClick={onOpen} className="w-full text-left">
        <div className="flex items-center gap-1.5">
          <span className="text-xs font-semibold text-gray-900 truncate">
            {contact.agent_name}
          </span>
          <span className="text-3xs text-gray-500 font-mono truncate">{contact.path}</span>
          {contact.unread_count > 0 && (
            <span className="ml-auto shrink-0 min-w-[16px] h-4 px-1 rounded-full bg-blue-600 text-white text-3xs font-bold flex items-center justify-center">
              {contact.unread_count}
            </span>
          )}
        </div>
        <div className="flex items-center gap-1 mt-0.5">
          <ChevronRightIcon className="w-3 h-3 text-blue-400 shrink-0" />
          <span className="text-2xs text-blue-600 font-mono truncate">
            {contact.session_alias || '(未命名会话)'}
          </span>
        </div>
        <p className="text-3xs text-gray-500 mt-0.5">
          {contact.mail_count} 封 · {time}
        </p>
      </button>

      <div className="reveal flex gap-1 mt-1.5">
        <button
          onClick={onCompose}
          title="写信给该地址"
          className="tap inline-flex items-center gap-1 px-2 py-0.5 rounded border border-gray-300 text-3xs text-gray-600 hover:bg-white"
        >
          <ComposeIcon className="w-3 h-3" />
          写信
        </button>
        <button
          onClick={onRequestArchive}
          title="归档该 name@path.session"
          className="tap inline-flex items-center gap-1 px-2 py-0.5 rounded border border-gray-300 text-3xs text-gray-600 hover:bg-white hover:text-red-600 hover:border-red-300"
        >
          <ArchiveIcon className="w-3 h-3" />
          归档
        </button>
      </div>
    </div>
  );
}