// src/components/CreatePost.jsx

import React, { useState } from 'react'
import { useNavigate } from 'react-router-dom'
import UploadPage from './UploadPage'
import { createPost } from '../api/posts'
import '../style/CreatePost.css'

export default function CreatePost() {
  const navigate = useNavigate()

  const [step, setStep] = useState('upload')     // 'upload' | 'detail'
  const [files, setFiles] = useState([])         // 本地 File 对象列表
  const [mediaUrls, setMediaUrls] = useState([]) // 上传后得到的 URL 列表

  // 详情表单字段
  const [title, setTitle]     = useState('')
  const [content, setContent] = useState('')
  const [topicId, setTopicId] = useState('')
  const [status, setStatus]   = useState('published')

  const [error, setError]     = useState(null)

  // 静态话题数据
  const TOPICS = [
    { id: 1, name: '世俱杯环球评大会' },
    { id: 2, name: '我的REDmentor' },
    { id: 3, name: '我染上了拼豆' },
    // …更多静态话题…
  ]

  // 上传页面回调 —— 上传完成后切换到“填写详情”步骤
  const handleUploadComplete = async uploadedFiles => {
    setFiles(uploadedFiles)

    // TODO: 改成真实上传逻辑，拿到真正的 media_urls
    const urls = await Promise.all(
      uploadedFiles.map(f => URL.createObjectURL(f))
    )
    setMediaUrls(urls)

    setStep('detail')
  }

  // 发布按钮
  const handleSubmit = async () => {
    if (!title.trim() || !content.trim()) {
      setError('标题和正文必填')
      return
    }
    setError(null)
    try {
      await createPost({
        user_id: 1,
        topic_id: topicId || undefined,
        title: title.trim(),
        content: content.trim(),
        media_urls: mediaUrls,
        status
      })
      // 发布成功后跳转回首页
      navigate('/home', { replace: true })
    } catch (e) {
      setError(e.message)
    }
  }

  // 渲染上传页
  if (step === 'upload') {
    return <UploadPage onComplete={handleUploadComplete} />
  }

  // 渲染详情页
  return (
    <div className="create-post">
      <h2>填写帖子内容</h2>
      {error && <div className="error">{error}</div>}

      {/* 已上传媒体预览 */}
      <div className="preview-media">
        {mediaUrls.map((url, i) => (
          <div key={i} className="preview-item">
            {files[i].type.startsWith('image/') ? (
              <img src={url} alt={`预览 ${i}`} />
            ) : (
              <video src={url} controls />
            )}
          </div>
        ))}
      </div>

      {/* 标题 */}
      <label className="form-label">
        标题（最多20字）
        <input
          type="text"
          maxLength={20}
          value={title}
          onChange={e => setTitle(e.target.value)}
          placeholder="填写标题会有更多赞哦~"
        />
        <span className="char-count">{title.length}/20</span>
      </label>

      {/* 正文 */}
      <label className="form-label">
        正文（最多1000字）
        <textarea
          maxLength={1000}
          value={content}
          onChange={e => setContent(e.target.value)}
          placeholder="输入正文描述，真诚有价值的分享予人温暖"
        />
        <span className="char-count">{content.length}/1000</span>
      </label>

      {/* 话题选择 */}
      <label className="form-label">
        选择话题（可选）
        <select
          value={topicId}
          onChange={e => setTopicId(e.target.value)}
        >
          <option value="">不添加话题</option>
          {TOPICS.map(t => (
            <option key={t.id} value={t.id}>
              #{t.name}
            </option>
          ))}
        </select>
      </label>

      {/* 发布状态 */}
      <div className="status-group">
        <label>
          <input
            type="radio"
            name="status"
            value="published"
            checked={status === 'published'}
            onChange={() => setStatus('published')}
          />
          立即发布
        </label>
        <label>
          <input
            type="radio"
            name="status"
            value="draft"
            checked={status === 'draft'}
            onChange={() => setStatus('draft')}
          />
          存为草稿
        </label>
      </div>

      {/* 操作按钮 */}
      <div className="btn-group">
        <button className="btn btn-primary" onClick={handleSubmit}>
          发布
        </button>
        <button className="btn btn-secondary" onClick={() => setStep('upload')}>
          上一步
        </button>
      </div>
    </div>
  )
}