'use client';

import { useEffect, useMemo, useState } from 'react';
import type { ColumnsType } from 'antd/es/table';
import {
  App, Button, Card, Checkbox, Input, Select, Space, Table, Tag,
} from 'antd';
import { api, errMsg } from '@/lib/api';
import { formatUtcTime } from '@/lib/format';
import { getAdmin } from '@/lib/auth';
import type { AdminInfo, AdminRole, PermissionGroup } from '@/lib/types';

const dt = (v: string | null) => (v ? formatUtcTime(v, 'YYYY-MM-DD HH:mm:ss') : '从未');

// 随机初始密码(排除易混字符 0O1lI),客户端生成、转交本人,后端只存 hash
function genPassword(len = 10): string {
  const chars = 'ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnpqrstuvwxyz23456789';
  let s = '';
  for (let i = 0; i < len; i += 1) s += chars[Math.floor(Math.random() * chars.length)];
  return s;
}

type View = 'list' | 'person' | 'roles' | 'roleForm';

// 「自定义」哨兵角色:不是共享角色,选它时可见页由本人逐页勾选(存 pages_override),与后端一致。
const CUSTOM_ROLE = 'custom';
const CUSTOM_LABEL = '自定义';

// ===== 只读权限矩阵:角色详情 / 人员「可见页面」预览共用(深色=有,灰色=无)=====
function PermMatrix({ catalog, pages }: { catalog: PermissionGroup[]; pages: string[] }) {
  const has = useMemo(() => new Set(pages), [pages]);
  return (
    <div style={{ border: '1px solid #f0f0f0', borderRadius: 8, overflow: 'hidden' }}>
      {catalog.map((g) => (
        <div key={g.group} style={{ display: 'flex', borderBottom: '1px solid #f0f2f5' }}>
          <div style={{ width: 150, flexShrink: 0, padding: '14px', fontWeight: 500, color: 'rgba(0,0,0,.85)' }}>
            {g.group}
          </div>
          <div style={{ flex: 1, padding: '12px 16px', display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '14px 28px' }}>
            {g.pages.map((p) => (
              // 深色=可见,灰色(--ink-3)=不可见
              <span key={p.key} style={{ fontSize: 13.5, color: has.has(p.key) ? 'rgba(0,0,0,.85)' : '#94a0b1' }}>
                {p.label}
              </span>
            ))}
          </div>
        </div>
      ))}
    </div>
  );
}

// ===== 可编辑权限矩阵:角色表单用(勾选框 + 分类全选/半选)=====
function PermEditor({
  catalog, value, onChange,
}: { catalog: PermissionGroup[]; value: string[]; onChange: (next: string[]) => void }) {
  const has = useMemo(() => new Set(value), [value]);
  const setPages = (s: Set<string>) => onChange(Array.from(s));
  const togglePage = (key: string) => {
    const n = new Set(has);
    if (n.has(key)) n.delete(key); else n.add(key);
    setPages(n);
  };
  const toggleGroup = (g: PermissionGroup, on: boolean) => {
    const n = new Set(has);
    g.pages.forEach((p) => (on ? n.add(p.key) : n.delete(p.key)));
    setPages(n);
  };
  return (
    <div style={{ border: '1px solid #f0f0f0', borderRadius: 8, overflow: 'hidden' }}>
      {catalog.map((g) => {
        const cnt = g.pages.filter((p) => has.has(p.key)).length;
        const all = cnt === g.pages.length && cnt > 0;
        return (
          <div key={g.group} style={{ display: 'flex', borderBottom: '1px solid #fafafa' }}>
            <div style={{ width: 140, flexShrink: 0, padding: '14px', background: '#fafbfd' }}>
              <Checkbox
                checked={all}
                indeterminate={cnt > 0 && !all}
                onChange={(e) => toggleGroup(g, e.target.checked)}
              >
                {g.group}
              </Checkbox>
            </div>
            <div style={{ flex: 1, padding: '12px 16px', display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '10px 24px' }}>
              {g.pages.map((p) => (
                <Checkbox key={p.key} checked={has.has(p.key)} onChange={() => togglePage(p.key)}>
                  {p.label}
                </Checkbox>
              ))}
            </div>
          </div>
        );
      })}
    </div>
  );
}

export default function AdminsPage() {
  const { message, modal } = App.useApp();
  const me = getAdmin();
  const isSuper = me?.role === 'super_admin';

  const [view, setView] = useState<View>('list');
  const [admins, setAdmins] = useState<AdminInfo[]>([]);
  const [roles, setRoles] = useState<AdminRole[]>([]);
  const [catalog, setCatalog] = useState<PermissionGroup[]>([]);
  const [loading, setLoading] = useState(false);

  const roleByName = useMemo(() => {
    const m: Record<string, AdminRole> = {};
    roles.forEach((r) => { m[r.name] = r; });
    return m;
  }, [roles]);
  const roleOptions = roles.map((r) => ({ value: r.name, label: r.label }));
  // 人员表单角色下拉:真实角色 + 末尾「自定义」。选「自定义」→ 下方可见页改为逐页勾选。
  const personRoleOptions = [...roleOptions, { value: CUSTOM_ROLE, label: CUSTOM_LABEL }];
  // 角色 key → 展示名(custom 显示「自定义」;查不到回退 key 原文)
  const roleLabelOf = (name: string) =>
    (name === CUSTOM_ROLE ? CUSTOM_LABEL : roleByName[name]?.label ?? name);

  const loadAll = async () => {
    setLoading(true);
    try {
      const [a, r, c] = await Promise.all([
        api.get<AdminInfo[]>('/admin/api/admins'),
        api.get<AdminRole[]>('/admin/api/roles'),
        api.get<PermissionGroup[]>('/admin/api/roles/catalog'),
      ]);
      setAdmins(a.data);
      setRoles(r.data);
      setCatalog(c.data);
    } catch (e) {
      message.error(errMsg(e));
    } finally {
      setLoading(false);
    }
  };
  useEffect(() => { loadAll(); }, []); // eslint-disable-line react-hooks/exhaustive-deps

  // ===== 人员表单(新增 / 编辑)状态 =====
  const [personEditing, setPersonEditing] = useState<AdminInfo | null>(null);
  const [personName, setPersonName] = useState('');
  const [personRole, setPersonRole] = useState('');
  const [initPw, setInitPw] = useState('');
  // 「自定义」角色时逐页勾选的可见页集(role==custom 才用到)
  const [personPages, setPersonPages] = useState<string[]>([]);

  const openCreatePerson = () => {
    setPersonEditing(null);
    setPersonName('');
    setPersonRole(roles.find((r) => !r.is_builtin)?.name ?? roles[0]?.name ?? 'operator');
    setPersonPages([]);
    setInitPw(genPassword());
    setView('person');
  };
  const openEditPerson = (a: AdminInfo) => {
    setPersonEditing(a);
    setPersonName(a.username);
    setPersonRole(a.role);
    // 编辑「自定义」用户时,回填其已勾选的可见页(供继续增删)
    setPersonPages(a.role === CUSTOM_ROLE ? (a.pages_override ?? []) : []);
    setInitPw(''); // 编辑态密码只读展示 a.password(已确定的登录密码),不用 initPw
    setView('person');
  };
  const copyText = (v: string) => {
    navigator.clipboard?.writeText(v);
    message.success('已复制到剪贴板');
  };
  // 密码展示框(对齐原型 .pw-show:虚线灰框 + 大号等宽 + 复制)
  const pwBox = (value: string) => (
    <div style={{ display: 'flex', alignItems: 'center', gap: 12, background: '#f4f6fa', border: '1px dashed #cbd5e1', borderRadius: 8, padding: '12px 14px' }}>
      <code style={{ flex: 1, fontFamily: '"DIN Alternate", "SF Mono", Consolas, monospace', fontSize: 22, fontWeight: 700, letterSpacing: 1, color: 'rgba(0,0,0,.85)' }}>{value}</code>
      <Button onClick={() => copyText(value)}>复制</Button>
    </div>
  );
  const isCustom = personRole === CUSTOM_ROLE;
  const submitPerson = async () => {
    if (isCustom && personPages.length === 0) { message.error('自定义角色请至少勾选一个可见页面'); return; }
    try {
      if (personEditing) {
        // 密码只读、不改;提交变更的角色 +(自定义时)勾选的可见页
        const roleChanged = personRole !== personEditing.role;
        const pagesChanged = isCustom
          && JSON.stringify(personPages) !== JSON.stringify(personEditing.pages_override ?? []);
        if (roleChanged || pagesChanged) {
          const payload: Record<string, unknown> = {};
          if (roleChanged) payload.role = personRole;
          // 自定义:带上勾选集(切到 custom 或改现有 custom 勾选都要);切回普通角色不带,后端会清空 override
          if (isCustom) payload.pages_override = personPages;
          await api.patch(`/admin/api/admins/${personEditing.id}`, payload);
        }
        message.success('已保存');
      } else {
        if (personName.trim().length < 3) { message.error('用户名至少 3 位'); return; }
        await api.post('/admin/api/admins', {
          username: personName.trim(),
          password: initPw,
          role: personRole,
          ...(isCustom ? { pages_override: personPages } : {}),
        });
        message.success('已创建,请把初始密码转交本人');
      }
      setView('list');
      loadAll();
    } catch (e) {
      message.error(errMsg(e));
    }
  };
  // ===== 列表操作 =====
  const changeRole = (a: AdminInfo, role: string) => {
    if (role === a.role) return;
    // 改成「自定义」需要逐页勾选 → 转去编辑页(列表里没有页选择器,直接切会得到空可见页)
    if (role === CUSTOM_ROLE) { openEditPerson({ ...a, role: CUSTOM_ROLE }); return; }
    modal.confirm({
      title: `把 ${a.username} 的角色改为 ${roleLabelOf(role)}?`,
      onOk: async () => {
        try { await api.patch(`/admin/api/admins/${a.id}`, { role }); message.success('已更新'); loadAll(); }
        catch (e) { message.error(errMsg(e)); }
      },
    });
  };
  const toggleStatus = (a: AdminInfo) => {
    const next = a.status === 'active' ? 'disabled' : 'active';
    modal.confirm({
      title: `${next === 'disabled' ? '禁用' : '启用'}管理员 ${a.username}?`,
      onOk: async () => {
        try { await api.patch(`/admin/api/admins/${a.id}`, { status: next }); message.success('已更新'); loadAll(); }
        catch (e) { message.error(errMsg(e)); }
      },
    });
  };
  const deletePerson = (a: AdminInfo) => {
    modal.confirm({
      title: '确认删除',
      content: `确定删除管理员「${a.username}」吗?删除后该账号将无法登录,不可恢复。`,
      okText: '确认删除', okButtonProps: { danger: true },
      onOk: async () => {
        try { await api.delete(`/admin/api/admins/${a.id}`); message.success('已删除'); loadAll(); }
        catch (e) { message.error(errMsg(e)); }
      },
    });
  };

  // ===== 角色设置状态 =====
  const [selRoleId, setSelRoleId] = useState<number | null>(null);
  const selRole = roles.find((r) => r.id === selRoleId) ?? roles[0] ?? null;
  const openRoles = () => {
    setSelRoleId((prev) => prev ?? roles[0]?.id ?? null);
    setView('roles');
  };

  // 角色表单(新增 / 编辑)
  const [roleEditing, setRoleEditing] = useState<AdminRole | null>(null);
  const [roleName, setRoleName] = useState('');
  const [rolePages, setRolePages] = useState<string[]>([]);
  const openCreateRole = () => {
    setRoleEditing(null); setRoleName(''); setRolePages([]); setView('roleForm');
  };
  const openEditRole = (r: AdminRole) => {
    setRoleEditing(r); setRoleName(r.label); setRolePages(r.pages); setView('roleForm');
  };
  const submitRole = async () => {
    if (!roleName.trim()) { message.error('请输入角色名称'); return; }
    try {
      if (roleEditing) {
        // 只改展示名 + 可见页(key 不可变)
        await api.patch(`/admin/api/roles/${roleEditing.id}`, { label: roleName.trim(), pages: rolePages });
        message.success('角色已保存');
      } else {
        await api.post('/admin/api/roles', { name: roleName.trim(), pages: rolePages });
        message.success('角色已创建');
      }
      await loadAll();
      setView('roles');
    } catch (e) {
      message.error(errMsg(e));
    }
  };
  const deleteRole = (r: AdminRole) => {
    modal.confirm({
      title: '确认删除角色',
      content: `确定删除角色「${r.label}」吗?${r.in_use > 0 ? `当前有 ${r.in_use} 名成员在用,需先改派。` : '此操作不可恢复。'}`,
      okText: '确认删除', okButtonProps: { danger: true },
      onOk: async () => {
        try { await api.delete(`/admin/api/roles/${r.id}`); message.success('已删除角色'); await loadAll(); setSelRoleId(null); }
        catch (e) { message.error(errMsg(e)); }
      },
    });
  };

  const columns: ColumnsType<AdminInfo> = [
    { title: 'ID', dataIndex: 'id', width: 70 },
    { title: '用户名', dataIndex: 'username' },
    {
      title: '角色', dataIndex: 'role', width: 170,
      // options 含「自定义」→ custom 用户在列表里显示为「自定义」;选它会转去编辑页勾选(见 changeRole)
      render: (r: string, a: AdminInfo) => (
        <Select size="small" value={r} style={{ width: 150 }} options={personRoleOptions} onChange={(v) => changeRole(a, v)} />
      ),
    },
    { title: '状态', dataIndex: 'status', width: 90, render: (s: string) => <Tag color={s === 'active' ? 'green' : 'default'}>{s === 'active' ? 'active' : '已禁用'}</Tag> },
    { title: '最后登录', dataIndex: 'last_login_at', width: 180, render: dt },
    {
      title: '操作', key: 'op', width: 200,
      render: (_: unknown, a: AdminInfo) => (
        <Space size="middle">
          <a onClick={() => openEditPerson(a)}>编辑</a>
          <a onClick={() => toggleStatus(a)}>{a.status === 'active' ? '禁用' : '启用'}</a>
          <a style={{ color: '#cf1322' }} onClick={() => deletePerson(a)}>删除</a>
        </Space>
      ),
    },
  ];

  // ============ 视图 1:管理员账号列表 ============
  if (view === 'list') {
    return (
      <div>
        <h2>权限管理</h2>
        <Space style={{ marginBottom: 16 }}>
          <Button type="primary" onClick={openCreatePerson}>+ 新增人员</Button>
          <Button onClick={openRoles}>角色设置</Button>
        </Space>
        <Table rowKey="id" columns={columns} dataSource={admins} loading={loading} pagination={false} />
      </div>
    );
  }

  // ============ 视图 2:新增 / 编辑人员 ============
  if (view === 'person') {
    const rolePagesPreview = roleByName[personRole]?.pages ?? [];
    return (
      <div>
        <Space style={{ marginBottom: 16 }}><a onClick={() => setView('list')}>‹ 返回</a></Space>
        <Card style={{ maxWidth: 720, margin: '0 auto' }}>
          <h2 style={{ fontSize: 19, fontWeight: 600, marginBottom: 22 }}>{personEditing ? '编辑人员' : '新增人员'}</h2>
          <div style={{ marginBottom: 20 }}>
            <div style={{ marginBottom: 8 }}>用户名<span style={{ color: '#cf1322' }}> *</span></div>
            <Input value={personName} disabled={!!personEditing} onChange={(e) => setPersonName(e.target.value)} placeholder="至少 3 位" />
            {personEditing && <div style={{ color: '#999', fontSize: 12, marginTop: 6 }}>用户名不可修改</div>}
          </div>

          {!personEditing ? (
            // 新增:系统生成初始密码(可换)
            <div style={{ marginBottom: 20 }}>
              <div style={{ display: 'flex', justifyContent: 'space-between', marginBottom: 8 }}>
                <span>初始密码</span>
                <a onClick={() => setInitPw(genPassword())}>换一个 ↻</a>
              </div>
              {pwBox(initPw)}
            </div>
          ) : personEditing.password ? (
            // 编辑:显示该成员已确定的登录密码(只读、不可换)
            <div style={{ marginBottom: 20 }}>
              <div style={{ marginBottom: 8 }}>登录密码</div>
              {pwBox(personEditing.password)}
              <div style={{ color: '#999', fontSize: 12, marginTop: 6 }}>该成员已确定的登录密码,可复制转交本人</div>
            </div>
          ) : (
            // 编辑:无留存明文(脚本/起后台建的超管)→ 不显示密码
            <div style={{ marginBottom: 20 }}>
              <div style={{ marginBottom: 8 }}>登录密码</div>
              <div style={{ color: '#999', fontSize: 13, padding: '6px 0' }}>该账号密码仅在后台创建时设定、系统未留存,不可查看。</div>
            </div>
          )}

          <div style={{ marginBottom: 20 }}>
            <div style={{ display: 'flex', justifyContent: 'space-between', marginBottom: 8 }}>
              <span>选择角色<span style={{ color: '#cf1322' }}> *</span></span>
              {isSuper && <a onClick={openRoles}>设置角色权限 ›</a>}
            </div>
            <Select value={personRole} options={personRoleOptions} onChange={setPersonRole} style={{ width: '100%' }} />
            <div style={{ color: '#999', fontSize: 12, marginTop: 6 }}>
              {isCustom
                ? '「自定义」:下方逐页勾选该成员可见的页面,仅对本人生效(不影响任何角色)'
                : '可见页面完全由所选角色决定;如需调整请到「角色设置」修改该角色'}
            </div>
          </div>

          <div>
            <div style={{ display: 'flex', justifyContent: 'space-between', marginBottom: 8 }}>
              <span>可见页面</span>
              <span style={{ color: '#999', fontSize: 12 }}>
                {isCustom ? '勾选本成员可见的页面' : '跟随所选角色,此处只读(深色=可见)'}
              </span>
            </div>
            {isCustom ? (
              <PermEditor catalog={catalog} value={personPages} onChange={setPersonPages} />
            ) : (
              <PermMatrix catalog={catalog} pages={personRole === 'super_admin' ? catalog.flatMap((g) => g.pages.map((p) => p.key)) : rolePagesPreview} />
            )}
          </div>

          <div style={{ marginTop: 24, textAlign: 'right' }}>
            <Space><Button onClick={() => setView('list')}>取消</Button><Button type="primary" onClick={submitPerson}>确定</Button></Space>
          </div>
        </Card>
      </div>
    );
  }

  // ============ 视图 3:角色设置(角色列表 + 只读权限详情)============
  if (view === 'roles') {
    return (
      <div>
        <Space style={{ marginBottom: 16 }}><a onClick={() => setView('list')}>‹ 返回</a><b>角色设置</b></Space>
        <div>
          <Button type="primary" style={{ marginBottom: 16 }} onClick={openCreateRole}>+ 新增角色权限</Button>
          <div style={{ display: 'flex', background: '#fff', border: '1px solid #e8ebf1', borderRadius: 10, boxShadow: '0 1px 3px rgba(16,24,40,.06)', overflow: 'hidden' }}>
            <div style={{ width: 176, flexShrink: 0, borderRight: '1px solid #eff1f6', padding: 8 }}>
              {roles.map((r) => (
                <div
                  key={r.id}
                  onClick={() => setSelRoleId(r.id)}
                  style={{
                    padding: '10px 14px', borderRadius: 8, cursor: 'pointer', marginBottom: 2,
                    background: selRole?.id === r.id ? '#e6f0ff' : undefined,
                    color: selRole?.id === r.id ? '#1677ff' : undefined,
                    fontWeight: selRole?.id === r.id ? 600 : undefined,
                  }}
                >
                  {r.label}{r.is_builtin && <Tag style={{ marginLeft: 6 }}>内建</Tag>}
                </div>
              ))}
            </div>
            <div style={{ flex: 1, minWidth: 0, padding: '18px 22px' }}>
              {selRole && (
                <>
                  <Space style={{ marginBottom: 16 }} size="middle">
                    <b style={{ fontSize: 16 }}>{selRole.label}</b>
                    {!selRole.is_builtin && <a onClick={() => openEditRole(selRole)}>编辑角色权限</a>}
                    {!selRole.is_builtin && <a style={{ color: '#cf1322' }} onClick={() => deleteRole(selRole)}>删除角色权限</a>}
                    {selRole.in_use > 0 && <span style={{ color: '#999', fontSize: 12 }}>{selRole.in_use} 名成员在用</span>}
                  </Space>
                  <PermMatrix catalog={catalog} pages={selRole.pages} />
                </>
              )}
            </div>
          </div>
        </div>
      </div>
    );
  }

  // ============ 视图 4:新增 / 编辑角色权限 ============
  return (
    <div>
      <Space style={{ marginBottom: 16 }}><a onClick={() => setView('roles')}>‹ 返回</a></Space>
      <Card style={{ maxWidth: 920, margin: '0 auto' }}>
        <h2 style={{ fontSize: 19, fontWeight: 600, marginBottom: 22 }}>{roleEditing ? '编辑角色权限' : '新增角色权限'}</h2>
        <div style={{ marginBottom: 20 }}>
          <div style={{ marginBottom: 8 }}>角色名称<span style={{ color: '#cf1322' }}> *</span></div>
          <Input value={roleName} onChange={(e) => setRoleName(e.target.value)} placeholder="如:运营专员 / 财务 / 审核" maxLength={32} />
        </div>
        <div>
          <div style={{ marginBottom: 8 }}>角色权限(可见页面)<span style={{ color: '#cf1322' }}> *</span></div>
          <PermEditor catalog={catalog} value={rolePages} onChange={setRolePages} />
        </div>
        <div style={{ marginTop: 24, textAlign: 'right' }}>
          <Space><Button onClick={() => setView('roles')}>取消</Button><Button type="primary" onClick={submitRole}>确定</Button></Space>
        </div>
      </Card>
    </div>
  );
}