import { useEffect, useState } from 'react'
import { Button, Card, Col, Container, Form, Row } from 'react-bootstrap'
import { Link, useParams } from 'react-router-dom'
import { createPost, getThread, listPostsByThread } from '../api/client'
import { useAuth } from '../context/AuthContext'
import { useTranslation } from 'react-i18next'

export default function ThreadView() {
  const { id } = useParams()
  const { token } = useAuth()
  const [thread, setThread] = useState(null)
  const [posts, setPosts] = useState([])
  const [error, setError] = useState('')
  const [loading, setLoading] = useState(true)
  const [body, setBody] = useState('')
  const [saving, setSaving] = useState(false)
  const { t } = useTranslation()

  useEffect(() => {
    setLoading(true)
    Promise.all([getThread(id), listPostsByThread(id)])
      .then(([threadData, postData]) => {
        setThread(threadData)
        setPosts(postData)
      })
      .catch((err) => setError(err.message))
      .finally(() => setLoading(false))
  }, [id])

  const handleSubmit = async (event) => {
    event.preventDefault()
    setSaving(true)
    setError('')
    try {
      await createPost({ body, threadId: id })
      setBody('')
      const updated = await listPostsByThread(id)
      setPosts(updated)
    } catch (err) {
      setError(err.message)
    } finally {
      setSaving(false)
    }
  }

  return (
    <Container className="py-5">
      {loading && <p className="bb-muted">{t('thread.loading')}</p>}
      {error && <p className="text-danger">{error}</p>}
      {thread && (
        <>
          <div className="bb-hero mb-4">
            <p className="bb-chip">{t('thread.label')}</p>
            <h2 className="mt-3">{thread.title}</h2>
            <p className="bb-muted mb-2">{thread.body}</p>
            {thread.forum && (
              <p className="bb-muted mb-0">
                {t('thread.category')}{' '}
                <Link to={`/forum/${thread.forum.id || thread.forum.split('/').pop()}`}>
                  {thread.forum.name || t('thread.back_to_category')}
                </Link>
              </p>
            )}
          </div>

          <Row className="g-4">
            <Col lg={7}>
              <h4 className="bb-section-title mb-3">{t('thread.replies')}</h4>
              {posts.length === 0 && (
                <p className="bb-muted">{t('thread.empty')}</p>
              )}
              {posts.map((post) => (
                <Card className="bb-card mb-3" key={post.id}>
                  <Card.Body>
                    <Card.Text>{post.body}</Card.Text>
                    <small className="bb-muted">
                      {post.author?.username || t('thread.anonymous')}
                    </small>
                  </Card.Body>
                </Card>
              ))}
            </Col>
            <Col lg={5}>
              <h4 className="bb-section-title mb-3">{t('thread.reply')}</h4>
              <div className="bb-form">
                {!token && (
                  <p className="bb-muted mb-3">{t('thread.login_hint')}</p>
                )}
                <Form onSubmit={handleSubmit}>
                  <Form.Group className="mb-3">
                    <Form.Label>{t('form.message')}</Form.Label>
                    <Form.Control
                      as="textarea"
                      rows={5}
                      placeholder={t('form.reply_placeholder')}
                      value={body}
                      onChange={(event) => setBody(event.target.value)}
                      disabled={!token || saving}
                      required
                    />
                  </Form.Group>
                  <Button type="submit" variant="dark" disabled={!token || saving}>
                    {saving ? t('form.posting') : t('form.post_reply')}
                  </Button>
                </Form>
              </div>
            </Col>
          </Row>
        </>
      )}
    </Container>
  )
}