import React, { useCallback, useEffect, useState } from 'react';
import { 
  Card, Form, Input, Button, DatePicker, Select,
  Typography, App, Divider, Row, Col, Upload, Space, Progress
} from 'antd';
import { 
  ArrowLeftOutlined, UploadOutlined, SaveOutlined, DeleteOutlined,
  VideoCameraAddOutlined, AudioOutlined
} from '@ant-design/icons';
import { useNavigate } from 'react-router-dom';
import dayjs from 'dayjs';
import httpService from '../services/httpService';
import { buildApiUrl, API_ENDPOINTS } from '../config/api';
import configService from '../utils/configService';
import { AUDIO_UPLOAD_ACCEPT, uploadMeetingAudio, validateMeetingAudioFile } from '../services/meetingAudioService';

const { Title, Text } = Typography;

const CreateMeeting = () => {
  const navigate = useNavigate();
  const { message } = App.useApp();
  const [form] = Form.useForm();
  const [loading, setLoading] = useState(false);
  const [users, setUsers] = useState([]);
  const [prompts, setPrompts] = useState([]);
  const [selectedAudioFile, setSelectedAudioFile] = useState(null);
  const [audioUploading, setAudioUploading] = useState(false);
  const [audioUploadProgress, setAudioUploadProgress] = useState(0);
  const [audioUploadMessage, setAudioUploadMessage] = useState('');
  const [maxAudioSize, setMaxAudioSize] = useState(() => configService.getCachedMaxAudioSize());

  const fetchUsers = useCallback(async () => {
    try {
      const res = await httpService.get(buildApiUrl(API_ENDPOINTS.USERS.LIST));
      setUsers(res.data.users || []);
    } catch {
      setUsers([]);
    }
  }, []);

  const fetchPrompts = useCallback(async () => {
    try {
      const res = await httpService.get(buildApiUrl(API_ENDPOINTS.PROMPTS.ACTIVE('MEETING_TASK')));
      setPrompts(res.data.prompts || []);
    } catch {
      setPrompts([]);
    }
  }, []);

  const loadAudioUploadConfig = useCallback(async () => {
    try {
      const nextMaxAudioSize = await configService.getMaxAudioSize();
      setMaxAudioSize(nextMaxAudioSize);
    } catch (error) {
      message.error(error?.message || '加载音频上传限制失败');
    }
  }, [message]);

  useEffect(() => {
    fetchUsers();
    fetchPrompts();
    loadAudioUploadConfig();
  }, [fetchPrompts, fetchUsers, loadAudioUploadConfig]);

  const handleAudioBeforeUpload = (file) => {
    if (!maxAudioSize) {
      message.error('系统音频上传限制未加载完成，请稍后重试');
      return Upload.LIST_IGNORE;
    }

    const validationMessage = validateMeetingAudioFile(file, maxAudioSize, configService.formatFileSize.bind(configService));
    if (validationMessage) {
      message.warning(validationMessage);
      return Upload.LIST_IGNORE;
    }

    setSelectedAudioFile(file);
    return false;
  };

  const clearSelectedAudio = () => {
    setSelectedAudioFile(null);
    setAudioUploadProgress(0);
    setAudioUploadMessage('');
  };

  const onFinish = async (values) => {
    setLoading(true);
    try {
      const payload = {
        ...values,
        meeting_time: values.meeting_time.format('YYYY-MM-DD HH:mm:ss'),
        attendee_ids: values.attendee_ids || [],
        tags: values.tags?.join(',') || ''
      };
      const res = await httpService.post(buildApiUrl(API_ENDPOINTS.MEETINGS.CREATE), payload);
      if (res.code === '200') {
        const meetingId = res.data.meeting_id;

        if (selectedAudioFile) {
          setAudioUploading(true);
          setAudioUploadProgress(0);
          setAudioUploadMessage('正在上传音频文件...');
          try {
            const uploadResponse = await uploadMeetingAudio({
              meetingId,
              file: selectedAudioFile,
              promptId: values.prompt_id,
              onUploadProgress: (progressEvent) => {
                if (progressEvent.total) {
                  setAudioUploadProgress(Math.min(100, Math.round((progressEvent.loaded * 100) / progressEvent.total)));
                }
                setAudioUploadMessage('正在上传音频文件...');
              },
            });
            setAudioUploadProgress(100);
            setAudioUploadMessage('上传完成，后台正在处理音频...');
            message.success(uploadResponse?.message || '会议创建成功，音频已进入后台处理');
          } catch (uploadError) {
            message.warning(uploadError.response?.data?.message || uploadError.response?.data?.detail || '会议已创建，但音频上传失败，请在详情页重试');
          } finally {
            setAudioUploading(false);
          }
        } else {
          message.success('会议创建成功');
        }

        navigate(`/meetings/${meetingId}`);
      }
    } catch (error) {
      message.error(error.response?.data?.message || error.response?.data?.detail || '创建失败');
    } finally {
      setLoading(false);
    }
  };

  return (
    <div className="create-meeting-modern" style={{ maxWidth: 800, margin: '0 auto', padding: '24px 0' }}>
      <Card variant="borderless" style={{ borderRadius: 16, boxShadow: '0 4px 20px rgba(0,0,0,0.05)' }}>
        <div style={{ display: 'flex', alignItems: 'center', marginBottom: 32 }}>
          <Button icon={<ArrowLeftOutlined />} shape="circle" onClick={() => navigate(-1)} style={{ marginRight: 16 }} />
          <Title level={3} style={{ margin: 0 }}>新建会议纪要</Title>
        </div>

        <Form form={form} layout="vertical" onFinish={onFinish} initialValues={{ meeting_time: dayjs() }}>
          <Form.Item label="会议主题" name="title" rules={[{ required: true, message: '请输入会议主题' }]}>
            <Input size="large" prefix={<VideoCameraAddOutlined />} placeholder="请输入会议主题..." />
          </Form.Item>

          <Row gutter={24}>
            <Col span={12}>
              <Form.Item label="开始时间" name="meeting_time" rules={[{ required: true }]}>
                <DatePicker showTime size="large" style={{ width: '100%' }} />
              </Form.Item>
            </Col>
            <Col span={12}>
              <Form.Item label="使用总结模板" name="prompt_id">
                <Select size="large" placeholder="选择总结模版">
                  {prompts.map(p => <Select.Option key={p.id} value={p.id}>{p.name}</Select.Option>)}
                </Select>
              </Form.Item>
            </Col>
          </Row>

          <Form.Item label="参会人员" name="attendee_ids">
            <Select mode="multiple" size="large" placeholder="可不选参会人">
              {users.map(u => <Select.Option key={u.user_id} value={u.user_id}>{u.caption}</Select.Option>)}
            </Select>
          </Form.Item>

          <Form.Item label="标签" name="tags">
            <Select mode="tags" size="large" placeholder="输入标签按回车" />
          </Form.Item>

          <Form.Item label="会议音频">
            <Card
              variant="borderless"
              style={{
                borderRadius: 14,
                border: '1px solid #d9e2f2',
                background: selectedAudioFile ? 'linear-gradient(135deg, #f8fbff 0%, #ffffff 100%)' : '#fbfdff',
                boxShadow: 'inset 0 1px 0 rgba(255,255,255,0.86)',
              }}
              styles={{ body: { padding: 18 } }}
            >
              <Space direction="vertical" size={14} style={{ width: '100%' }}>
                <div style={{ display: 'flex', justifyContent: 'space-between', gap: 16, alignItems: 'flex-start' }}>
                  <div>
                    <Text strong style={{ display: 'block', marginBottom: 4 }}>上传会议音频</Text>
                    <Text type="secondary">
                      创建后会自动沿用会议详情页同一套上传与转录逻辑。支持 {AUDIO_UPLOAD_ACCEPT.replace(/\./g, '').toUpperCase()}，
                      最大 {maxAudioSize ? configService.formatFileSize(maxAudioSize) : '加载中'}。
                    </Text>
                  </div>
                  <Upload accept={AUDIO_UPLOAD_ACCEPT} showUploadList={false} beforeUpload={handleAudioBeforeUpload}>
                    <Button icon={<UploadOutlined />} disabled={audioUploading}>选择音频</Button>
                  </Upload>
                </div>

                {selectedAudioFile ? (
                  <div
                    style={{
                      display: 'flex',
                      justifyContent: 'space-between',
                      alignItems: 'center',
                      gap: 16,
                      padding: '12px 14px',
                      borderRadius: 12,
                      background: '#ffffff',
                      border: '1px solid #dbe7f5',
                    }}
                  >
                    <Space size={12}>
                      <div
                        style={{
                          width: 36,
                          height: 36,
                          borderRadius: 12,
                          display: 'grid',
                          placeItems: 'center',
                          background: '#edf4ff',
                          color: '#1d4ed8',
                        }}
                      >
                        <AudioOutlined />
                      </div>
                      <div>
                        <Text strong style={{ display: 'block' }}>{selectedAudioFile.name}</Text>
                        <Text type="secondary">{configService.formatFileSize(selectedAudioFile.size)}</Text>
                      </div>
                    </Space>
                    <Button
                      type="text"
                      icon={<DeleteOutlined />}
                      onClick={clearSelectedAudio}
                      disabled={audioUploading}
                    >
                      移除
                    </Button>
                  </div>
                ) : (
                  <div
                    style={{
                      borderRadius: 12,
                      border: '1px dashed #c7d5ea',
                      padding: '18px 16px',
                      background: '#ffffff',
                      color: 'rgba(17, 43, 78, 0.66)',
                      textAlign: 'center',
                    }}
                  >
                    可选。若现在不上传，也可以创建后在会议详情中补传。
                  </div>
                )}

                {audioUploading ? (
                  <div
                    style={{
                      padding: '12px 14px',
                      borderRadius: 12,
                      background: '#f0f7ff',
                      border: '1px solid #bfdbfe',
                    }}
                  >
                    <div style={{ display: 'flex', justifyContent: 'space-between', marginBottom: 8 }}>
                      <Text strong>音频上传中</Text>
                      <Text strong style={{ color: '#1677ff' }}>{audioUploadProgress}%</Text>
                    </div>
                    <Text type="secondary" style={{ display: 'block', marginBottom: 10 }}>
                      {audioUploadMessage || '正在上传音频文件...'}
                    </Text>
                    <Progress percent={audioUploadProgress} status="active" strokeColor={{ from: '#69b1ff', to: '#1677ff' }} />
                  </div>
                ) : null}
              </Space>
            </Card>
          </Form.Item>

          <Divider />

          <Form.Item>
            <Button type="primary" htmlType="submit" size="large" icon={<SaveOutlined />} loading={loading || audioUploading} block style={{ height: 50, fontSize: 16, borderRadius: 8 }}>
              {selectedAudioFile ? '创建并上传音频' : '创建并进入详情'}
            </Button>
          </Form.Item>
        </Form>
      </Card>
    </div>
  );
};

export default CreateMeeting;