import { AlertTriangle, Loader2, Trash2, X } from 'lucide-react'
import { FormEvent, useEffect, useState } from 'react'
import { api } from '../api'
import type { Course } from '../types'

interface DeleteCourseModalProps {
  isOpen: boolean
  onClose: () => void
  course: Course
  onSuccess: () => void
}

export function DeleteCourseModal({
  isOpen,
  onClose,
  course,
  onSuccess
}: DeleteCourseModalProps) {
  const [confirmName, setConfirmName] = useState('')
  const [busy, setBusy] = useState(false)
  const [error, setError] = useState('')

  useEffect(() => {
    if (isOpen) {
      setConfirmName('')
      setError('')
      setBusy(false)
    }
  }, [isOpen])

  // 监听 ESC 键关闭
  useEffect(() => {
    function handleKeyDown(e: KeyboardEvent) {
      if (e.key === 'Escape' && isOpen && !busy) {
        onClose()
      }
    }
    window.addEventListener('keydown', handleKeyDown)
    return () => window.removeEventListener('keydown', handleKeyDown)
  }, [isOpen, busy, onClose])

  if (!isOpen) return null

  const isMatch = confirmName.trim() === course.name.trim()

  async function handleSubmit(e: FormEvent) {
    e.preventDefault()
    if (!isMatch) {
      setError('输入的课程名称不一致，请核对后重试')
      return
    }

    setBusy(true)
    setError('')
    try {
      await api.deleteCourse(course.id)
      onSuccess()
    } catch (err) {
      setError((err as Error).message || '删除课程失败，请稍后重试')
      setBusy(false)
    }
  }

  return (
    <div
      className="modal-backdrop"
      onClick={(e) => {
        if (e.target === e.currentTarget && !busy) {
          onClose()
        }
      }}
    >
      <div className="modal-dialog delete-course-modal" role="dialog" aria-modal="true">
        <div className="modal-header">
          <div className="modal-header-simple-title">
            <h3>删除课程</h3>
          </div>
          <button
            type="button"
            className="close-modal-btn"
            onClick={onClose}
            disabled={busy}
            aria-label="关闭"
          >
            <X size={18} />
          </button>
        </div>

        <form onSubmit={handleSubmit} className="modal-form-content">
          <div className="delete-modal-body">
            <div className="danger-alert-card">
              <p>
                此操作<strong>无法撤销</strong>。该课程及其关联的 <strong>{course.episodes?.length || 0} 个分集</strong>、<strong>{course.assets?.length || 0} 份素材文件</strong>和讲师信息都将被永久删除。
              </p>
            </div>

            <div className="form-group">
              <label className="form-label" htmlFor="delete-course-input">
                请输入课程名称进行确认：
              </label>
              <div className="target-course-name-box">
                <code>{course.name}</code>
              </div>
              <input
                id="delete-course-input"
                type="text"
                autoFocus
                value={confirmName}
                onChange={(e) => {
                  setConfirmName(e.target.value)
                  if (error) setError('')
                }}
                placeholder="在此输入完整的课程名称"
                disabled={busy}
                className="delete-confirm-input"
              />
            </div>

            {error && <div className="notice notice-error">{error}</div>}
          </div>

          <div className="modal-footer">
            <button
              type="button"
              className="secondary-button"
              onClick={onClose}
              disabled={busy}
            >
              取消
            </button>
            <button
              type="submit"
              className="danger-button danger-submit-btn"
              disabled={!isMatch || busy}
            >
              {busy ? (
                <>
                  <Loader2 size={16} className="spin" />
                  正在删除…
                </>
              ) : (
                <>
                  <Trash2 size={16} />
                  确认彻底删除
                </>
              )}
            </button>
          </div>
        </form>
      </div>
    </div>
  )
}