import { useState } from 'react';
import * as api from '../api/client';
import { KeyIcon, CopyIcon, TrashIcon, PlusIcon, CheckIcon } from './icons';

/** 密钥类型的中文说明，创建表单与列表共用一份文案 */
export const KEY_TYPE_LABEL: Record<api.KeyType, string> = {
  permanent: '长期',
  one_time: '一次性',
  timed: '限时'
};

const KEY_TYPE_HINT: Record<api.KeyType, string> = {
  permanent: '永不过期，可重复使用',
  one_time: '首次使用后立即失效',
  timed: '指定小时数后过期'
};

/** 一条密钥在列表里的状态：过期/已用完/可用 */
function keyState(k: { key_type: api.KeyType; expires_at: string | null; used_at: string | null }) {
  if (k.key_type === 'one_time' && k.used_at) return { text: '已使用', cls: 'text-gray-400' };
  if (k.key_type === 'timed' && k.expires_at && new Date(k.expires_at) < new Date())
    return { text: '已过期', cls: 'text-red-500' };
  return { text: '可用', cls: 'text-green-600' };
}

/**
 * 新签发密钥的一次性展示条。
 *
 * 密钥全文只在创建响应里出现一次，服务端之后只返回前 8 位，
 * 所以这里必须明确提示「关掉就再也看不到」，而不是让用户以为随时能回来复制。
 */
function NewKeyBanner({ token, onDismiss }: { token: string; onDismiss: () => void }) {
  const [copied, setCopied] = useState(false);

  const copy = async () => {
    try {
      await navigator.clipboard.writeText(token);
      setCopied(true);
      setTimeout(() => setCopied(false), 1500);
    } catch {
      /* 无剪贴板权限时用户可手动选中 */
    }
  };

  return (
    <div className="border border-amber-300 bg-amber-50 rounded-md p-3 space-y-2">
      <div className="text-xs font-medium text-amber-900">
        密钥已创建。全文仅显示这一次，关闭后无法再次查看。
      </div>
      <div className="flex items-center gap-2">
        <code className="flex-1 text-[11px] font-mono bg-white border border-amber-200 rounded px-2 py-1.5 break-all">
          {token}
        </code>
        <button
          onClick={copy}
          className="tap shrink-0 flex items-center gap-1 text-xs px-2 py-1.5 border border-amber-300 rounded hover:bg-amber-100"
        >
          {copied ? <CheckIcon className="w-3.5 h-3.5" /> : <CopyIcon className="w-3.5 h-3.5" />}
          {copied ? '已复制' : '复制'}
        </button>
        <button onClick={onDismiss} className="tap shrink-0 text-xs text-amber-800 hover:underline">
          我已保存
        </button>
      </div>
    </div>
  );
}

interface CreateFormProps {
  /** Agent 密钥面板会多出「绑定 Agent」与「登记已有密钥」两项 */
  variant: 'agent' | 'user';
  busy: boolean;
  onSubmit: (payload: api.CreateKeyPayload) => void;
}

function CreateForm({ variant, busy, onSubmit }: CreateFormProps) {
  const [open, setOpen] = useState(false);
  const [keyType, setKeyType] = useState<api.KeyType>('permanent');
  const [label, setLabel] = useState('');
  const [hours, setHours] = useState(24);
  const [agentName, setAgentName] = useState('');
  const [keyToken, setKeyToken] = useState('');

  if (!open) {
    return (
      <button
        onClick={() => setOpen(true)}
        className="flex items-center gap-1.5 text-xs px-3 py-1.5 border border-gray-300 rounded-md hover:bg-gray-50"
      >
        <PlusIcon className="w-3.5 h-3.5" />
        新建密钥
      </button>
    );
  }

  const submit = () => {
    const payload: api.CreateKeyPayload = { key_type: keyType, label: label.trim() };
    if (keyType === 'timed') payload.expires_hours = hours;
    if (variant === 'agent') {
      if (agentName.trim()) payload.agent_name = agentName.trim();
      if (keyToken.trim()) payload.key_token = keyToken.trim();
    }
    onSubmit(payload);
    setOpen(false);
    setLabel('');
    setAgentName('');
    setKeyToken('');
  };

  return (
    <div className="border border-gray-200 rounded-md p-3 space-y-2.5 bg-gray-50">
      <div className="grid grid-cols-1 sm:grid-cols-3 gap-2">
        {(Object.keys(KEY_TYPE_LABEL) as api.KeyType[]).map(t => (
          <button
            key={t}
            onClick={() => setKeyType(t)}
            className={`text-left px-2.5 py-2 rounded border text-xs ${
              keyType === t
                ? 'border-blue-400 bg-white ring-2 ring-blue-100'
                : 'border-gray-200 bg-white hover:border-gray-300'
            }`}
          >
            <div className="font-medium text-gray-900">{KEY_TYPE_LABEL[t]}</div>
            <div className="text-[10px] text-gray-500 mt-0.5">{KEY_TYPE_HINT[t]}</div>
          </button>
        ))}
      </div>

      <div className="flex gap-2">
        <input
          value={label}
          onChange={e => setLabel(e.target.value)}
          placeholder="备注（如 我的笔记本 / CI 机器）"
          className="flex-1 text-xs border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-blue-100"
        />
        {keyType === 'timed' && (
          <div className="flex items-center gap-1">
            <input
              type="number"
              min={1}
              value={hours}
              onChange={e => setHours(Math.max(1, Number(e.target.value) || 1))}
              className="w-20 text-xs border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-blue-100"
            />
            <span className="text-[11px] text-gray-500">小时后过期</span>
          </div>
        )}
      </div>

      {variant === 'agent' && (
        <div className="space-y-2">
          <input
            value={agentName}
            onChange={e => setAgentName(e.target.value)}
            placeholder="绑定到 Agent（留空 = 首次注册时自动落定）"
            className="w-full text-xs border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-blue-100"
          />
          <input
            value={keyToken}
            onChange={e => setKeyToken(e.target.value)}
            placeholder="登记插件本地生成的密钥（留空 = 由服务器生成）"
            className="w-full text-xs font-mono border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-blue-100"
          />
        </div>
      )}

      <div className="flex items-center gap-2">
        <div className="flex-1" />
        <button onClick={() => setOpen(false)} className="text-xs text-gray-600 hover:text-gray-900">
          取消
        </button>
        <button
          onClick={submit}
          disabled={busy}
          className="tap text-xs px-3 py-1.5 rounded bg-blue-600 text-white hover:bg-blue-700 disabled:opacity-40"
        >
          创建
        </button>
      </div>
    </div>
  );
}

/**
 * 密钥面板。Agent 密钥（管理员）与用户连接密钥共用同一套渲染，
 * 差异用 variant 表达：只有 Agent 密钥能绑定 Agent 名、能登记客户端已生成的密钥。
 */
export default function KeyPanel({
  variant,
  keys,
  loading,
  error,
  newToken,
  onCreate,
  onDelete,
  onBind,
  onDismissToken
}: {
  variant: 'agent' | 'user';
  keys: (api.AgentKey | api.UserKey)[];
  loading: boolean;
  error: string | null;
  newToken: string | null;
  onCreate: (payload: api.CreateKeyPayload) => void;
  onDelete: (id: string) => void;
  onBind?: (id: string, agentName: string) => void;
  onDismissToken: () => void;
}) {
  const [bindingID, setBindingID] = useState<string | null>(null);
  const [bindName, setBindName] = useState('');

  return (
    <div className="space-y-3">
      <div className="flex items-center gap-2">
        <KeyIcon className="w-4 h-4 text-gray-500" />
        <h3 className="text-sm font-semibold text-gray-900">
          {variant === 'agent' ? 'Agent 接入密钥' : '客户端连接密钥'}
        </h3>
        <div className="flex-1" />
        <CreateForm variant={variant} busy={loading} onSubmit={onCreate} />
      </div>

      <p className="text-[11px] text-gray-500">
        {variant === 'agent'
          ? 'Agent 用该密钥注册、收发邮件与订阅通知。插件首次安装会在本地生成一把密钥并打印出来，把它填到「登记」框即可。'
          : '第三方客户端用该密钥访问自己的邮箱（Authorization: Bearer）。它不能用于注册 Agent。'}
      </p>

      {error && <div className="text-xs text-red-600">{error}</div>}
      {newToken && <NewKeyBanner token={newToken} onDismiss={onDismissToken} />}

      {keys.length === 0 ? (
        <div className="text-xs text-gray-400 py-3">暂无密钥</div>
      ) : (
        <div className="border border-gray-200 rounded-md divide-y divide-gray-100">
          {keys.map(k => {
            const st = keyState(k);
            const agentKey = variant === 'agent' ? (k as api.AgentKey) : null;
            return (
              <div key={k.key_id} className="px-3 py-2.5 flex items-center gap-x-3 gap-y-1 flex-wrap">
                <code className="text-[11px] font-mono text-gray-700 w-24 shrink-0">
                  {k.token_hint}
                </code>
                <div className="min-w-0 flex-1">
                  <div className="text-xs text-gray-900 truncate">
                    {k.label || <span className="text-gray-400">（无备注）</span>}
                  </div>
                  <div className="text-[10px] text-gray-500 mt-0.5">
                    {KEY_TYPE_LABEL[k.key_type]}
                    {k.expires_at && ` · ${new Date(k.expires_at).toLocaleString()} 过期`}
                    {agentKey &&
                      (agentKey.agent_name ? ` · ${agentKey.agent_name}` : ' · 待绑定')}
                  </div>
                </div>
                <span className={`text-[10px] shrink-0 ${st.cls}`}>{st.text}</span>

                {agentKey && onBind && bindingID === k.key_id ? (
                  <div className="flex items-center gap-1 shrink-0">
                    <input
                      value={bindName}
                      onChange={e => setBindName(e.target.value)}
                      placeholder="Agent 名"
                      className="w-28 text-[11px] border border-gray-300 rounded px-1.5 py-1"
                    />
                    <button
                      onClick={() => {
                        if (bindName.trim()) onBind(k.key_id, bindName.trim());
                        setBindingID(null);
                        setBindName('');
                      }}
                      className="text-[11px] text-blue-600 hover:underline"
                    >
                      确定
                    </button>
                    <button
                      onClick={() => setBindingID(null)}
                      className="text-[11px] text-gray-500 hover:underline"
                    >
                      取消
                    </button>
                  </div>
                ) : (
                  agentKey &&
                  onBind && (
                    <button
                      onClick={() => {
                        setBindingID(k.key_id);
                        setBindName(agentKey.agent_name ?? '');
                      }}
                      className="text-[11px] text-gray-500 hover:text-gray-900 shrink-0"
                    >
                      绑定
                    </button>
                  )
                )}

                <button
                  onClick={() => onDelete(k.key_id)}
                  title="吊销"
                  className="shrink-0 text-gray-400 hover:text-red-600"
                >
                  <TrashIcon className="w-3.5 h-3.5" />
                </button>
              </div>
            );
          })}
        </div>
      )}
    </div>
  );
}