"use client";

import { useEffect, useState } from "react";
import {
  Button,
  Chip,
  Input,
  Label,
  ListBox,
  Modal,
  Select,
  Spinner,
  Table,
  TextField,
} from "@heroui/react";
import { Pencil } from "@gravity-ui/icons";
import { api, type UserRow } from "@/lib/api";
import { useSession } from "@/lib/auth-client";

type CreateForm = {
  name: string;
  email: string;
  username: string;
  password: string;
  role: string;
};

type EditForm = {
  name: string;
  username: string;
  role: string;
};

const emptyCreate: CreateForm = { name: "", email: "", username: "", password: "", role: "user" };

const ROLE_OPTIONS = [
  { key: "user", label: "用户" },
  { key: "admin", label: "管理员" },
];

export default function UsersPage() {
  const { data: session } = useSession();
  const currentUserId = session?.user?.id;

  const [users, setUsers] = useState<UserRow[]>([]);
  const [loading, setLoading] = useState(true);
  const [updating, setUpdating] = useState<string | null>(null);

  const [createForm, setCreateForm] = useState<CreateForm>(emptyCreate);
  const [editTarget, setEditTarget] = useState<UserRow | null>(null);
  const [editForm, setEditForm] = useState<EditForm>({ name: "", username: "", role: "user" });
  const [saving, setSaving] = useState(false);

  const load = async () => {
    setLoading(true);
    try {
      setUsers(await api.users.list());
    } catch {
      // possibly not admin — show empty
    } finally {
      setLoading(false);
    }
  };

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

  const openEdit = (u: UserRow) => {
    setEditTarget(u);
    setEditForm({ name: u.name ?? "", username: u.username ?? "", role: u.role ?? "user" });
  };

  const handleCreate = async () => {
    setSaving(true);
    try {
      await api.users.create({
        name: createForm.name,
        email: createForm.email,
        password: createForm.password,
        username: createForm.username || undefined,
        role: createForm.role,
      });
      setCreateForm(emptyCreate);
      await load();
    } finally {
      setSaving(false);
    }
  };

  const handleEdit = async () => {
    if (!editTarget) return;
    setSaving(true);
    try {
      await api.users.update(editTarget.id, {
        name: editForm.name || undefined,
        username: editForm.username || null,
        role: editForm.role,
      });
      await load();
    } finally {
      setSaving(false);
    }
  };

  const toggleBan = async (u: UserRow) => {
    setUpdating(u.id);
    try {
      await api.users.update(u.id, {
        banned: !u.banned,
        banReason: u.banned ? null : "管理员封禁",
      });
      await load();
    } finally {
      setUpdating(null);
    }
  };

  const isEditingSelf = editTarget?.id === currentUserId;

  return (
    <div className="space-y-4">
      <div className="flex flex-wrap items-start justify-between gap-3">
        <div>
          <h1 className="text-xl font-semibold text-foreground">用户管理</h1>
          <p className="mt-0.5 text-sm text-muted">共 {users.length} 位用户（仅管理员可见）</p>
        </div>
        <Modal>
          <Button variant="secondary" onPress={() => setCreateForm(emptyCreate)}>
            新增用户
          </Button>
          <Modal.Backdrop>
            <Modal.Container scroll="outside">
              <Modal.Dialog className="sm:max-w-105">
                <Modal.CloseTrigger />
                <Modal.Header>
                  <Modal.Heading>新增用户</Modal.Heading>
                </Modal.Header>
                <Modal.Body className="space-y-3">
                  <TextField fullWidth>
                    <Label className="text-sm font-medium">显示名称</Label>
                    <Input
                      placeholder="对外显示的名称"
                      value={createForm.name}
                      onChange={(e) => setCreateForm({ ...createForm, name: e.target.value })}
                    />
                  </TextField>
                  <TextField fullWidth>
                    <Label className="text-sm font-medium">邮箱</Label>
                    <Input
                      type="email"
                      placeholder="user@example.com"
                      value={createForm.email}
                      onChange={(e) => setCreateForm({ ...createForm, email: e.target.value })}
                    />
                  </TextField>
                  <TextField fullWidth>
                    <Label className="text-sm font-medium">登录名</Label>
                    <Input
                      placeholder="创建账号的登录名"
                      value={createForm.username}
                      onChange={(e) => setCreateForm({ ...createForm, username: e.target.value })}
                    />
                  </TextField>
                  <TextField fullWidth>
                    <Label className="text-sm font-medium">密码</Label>
                    <Input
                      autoComplete="new-password"
                      type="password"
                      placeholder="创建账号的密码"
                      value={createForm.password}
                      onChange={(e) => setCreateForm({ ...createForm, password: e.target.value })}
                    />
                  </TextField>
                  <div className="flex flex-col gap-1">
                    <Label className="text-sm font-medium">角色</Label>
                    <Select
                      fullWidth
                      selectedKey={createForm.role}
                      onSelectionChange={(key) =>
                        setCreateForm({ ...createForm, role: String(key) })
                      }
                    >
                      <Select.Trigger>
                        <Select.Value />
                        <Select.Indicator />
                      </Select.Trigger>
                      <Select.Popover>
                        <ListBox>
                          {ROLE_OPTIONS.map((r) => (
                            <ListBox.Item key={r.key} id={r.key}>
                              {r.label}
                            </ListBox.Item>
                          ))}
                        </ListBox>
                      </Select.Popover>
                    </Select>
                  </div>
                </Modal.Body>
                <Modal.Footer className="flex justify-end gap-2">
                  <Button slot="close" variant="ghost">
                    取消
                  </Button>
                  <Button
                    isDisabled={
                      saving || !createForm.name || !createForm.email || !createForm.password
                    }
                    slot="close"
                    onPress={handleCreate}
                  >
                    {saving ? <Spinner size="sm" /> : "创建"}
                  </Button>
                </Modal.Footer>
              </Modal.Dialog>
            </Modal.Container>
          </Modal.Backdrop>
        </Modal>
      </div>

      <Table>
        <Table.ScrollContainer>
          <Table.Content aria-label="用户列表" className="min-w-187.5">
            <Table.Header>
              <Table.Column isRowHeader>用户</Table.Column>
              <Table.Column>邮箱</Table.Column>
              <Table.Column>登录名</Table.Column>
              <Table.Column>角色</Table.Column>
              <Table.Column>状态</Table.Column>
              <Table.Column>注册时间</Table.Column>
              <Table.Column className="text-end">操作</Table.Column>
            </Table.Header>
            <Table.Body
              renderEmptyState={() => (
                <div className="py-8 text-center text-sm text-muted">
                  {loading ? "加载中…" : "暂无用户或无权限"}
                </div>
              )}
            >
              {users.map((u) => (
                <Table.Row key={u.id} id={u.id}>
                  <Table.Cell>
                    <div className="font-medium">{u.name ?? "—"}</div>
                  </Table.Cell>
                  <Table.Cell className="text-sm">{u.email}</Table.Cell>
                  <Table.Cell className="font-mono text-sm">{u.username ?? "—"}</Table.Cell>
                  <Table.Cell>
                    <Chip
                      color={u.role === "admin" ? "warning" : "success"}
                      size="sm"
                      variant="soft"
                    >
                      {u.role === "admin" ? "管理员" : "用户"}
                    </Chip>
                  </Table.Cell>
                  <Table.Cell>
                    {u.banned ? (
                      <Chip color="danger" size="sm" variant="soft">
                        已封禁
                      </Chip>
                    ) : (
                      <Chip color="success" size="sm" variant="soft">
                        正常
                      </Chip>
                    )}
                  </Table.Cell>
                  <Table.Cell className="text-sm">
                    {new Date(u.createdAt).toLocaleString("zh-CN")}
                  </Table.Cell>
                  <Table.Cell>
                    <div className="flex justify-end gap-1">
                      {/* Edit button */}
                      <Modal>
                        <Button isIconOnly size="sm" variant="tertiary" onPress={() => openEdit(u)}>
                          <Pencil className="size-4" />
                        </Button>
                        <Modal.Backdrop>
                          <Modal.Container scroll="outside">
                            <Modal.Dialog className="sm:max-w-105">
                              <Modal.CloseTrigger />
                              <Modal.Header>
                                <Modal.Heading>编辑用户</Modal.Heading>
                              </Modal.Header>
                              <Modal.Body className="space-y-3">
                                <TextField fullWidth>
                                  <Label className="text-sm font-medium">姓名</Label>
                                  <Input
                                    placeholder="用户姓名"
                                    value={editForm.name}
                                    onChange={(e) =>
                                      setEditForm({ ...editForm, name: e.target.value })
                                    }
                                  />
                                </TextField>
                                <TextField fullWidth>
                                  <Label className="text-sm font-medium">登录名</Label>
                                  <Input
                                    placeholder="用户登录名"
                                    value={editForm.username}
                                    onChange={(e) =>
                                      setEditForm({ ...editForm, username: e.target.value })
                                    }
                                  />
                                </TextField>
                                {!isEditingSelf && (
                                  <div className="flex flex-col gap-1">
                                    <Label className="text-sm font-medium">角色</Label>
                                    <Select
                                      fullWidth
                                      selectedKey={editForm.role}
                                      onSelectionChange={(key) =>
                                        setEditForm({ ...editForm, role: String(key) })
                                      }
                                    >
                                      <Select.Trigger>
                                        <Select.Value />
                                        <Select.Indicator />
                                      </Select.Trigger>
                                      <Select.Popover>
                                        <ListBox>
                                          {ROLE_OPTIONS.map((r) => (
                                            <ListBox.Item key={r.key} id={r.key}>
                                              {r.label}
                                            </ListBox.Item>
                                          ))}
                                        </ListBox>
                                      </Select.Popover>
                                    </Select>
                                  </div>
                                )}
                              </Modal.Body>
                              <Modal.Footer className="flex justify-end gap-2">
                                <Button slot="close" variant="ghost">
                                  取消
                                </Button>
                                <Button isDisabled={saving} slot="close" onPress={handleEdit}>
                                  {saving ? <Spinner size="sm" /> : "保存"}
                                </Button>
                              </Modal.Footer>
                            </Modal.Dialog>
                          </Modal.Container>
                        </Modal.Backdrop>
                      </Modal>
                      {/* Ban / Unban button — disabled for current account */}
                      <Button
                        isDisabled={u.id === currentUserId || updating === u.id}
                        size="sm"
                        variant={u.banned ? "tertiary" : "danger-soft"}
                        onPress={() => toggleBan(u)}
                      >
                        {updating === u.id ? <Spinner size="sm" /> : u.banned ? "解封" : "封禁"}
                      </Button>
                    </div>
                  </Table.Cell>
                </Table.Row>
              ))}
            </Table.Body>
          </Table.Content>
        </Table.ScrollContainer>
      </Table>
    </div>
  );
}