import { NextRequest, NextResponse } from 'next/server'
import nodemailer from 'nodemailer'
import { createApproveToken } from '@/lib/token'

interface ChannelSelection {
  id: string
  name: string
  country: string
  categories: string[]
}

export async function POST(request: NextRequest) {
  try {
    const body = await request.json()
    const { email, channels } = body as { email: string; channels: ChannelSelection[] }

    // Validate email
    const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/
    if (!email || !emailRegex.test(email)) {
      return NextResponse.json(
        { error: 'A valid email is required' },
        { status: 400 }
      )
    }

    // Validate channels
    if (!Array.isArray(channels) || channels.length === 0 || channels.length > 20) {
      return NextResponse.json(
        { error: 'Select between 1 and 20 channels' },
        { status: 400 }
      )
    }

    for (const ch of channels) {
      if (!ch.id || !ch.name) {
        return NextResponse.json(
          { error: 'Invalid channel data' },
          { status: 400 }
        )
      }
    }

    const smtpHost = process.env.SMTP_HOST
    const smtpUser = process.env.SMTP_USER
    const smtpPass = process.env.SMTP_PASS
    if (!smtpHost || !smtpUser || !smtpPass) {
      console.error('SMTP credentials not configured')
      return NextResponse.json(
        { error: 'Email service not configured' },
        { status: 500 }
      )
    }

    const adminEmail = process.env.ADMIN_EMAIL || 'jeff@jeffemmett.com'

    const transporter = nodemailer.createTransport({
      host: smtpHost,
      port: Number(process.env.SMTP_PORT) || 587,
      secure: false,
      auth: { user: smtpUser, pass: smtpPass },
      tls: { rejectUnauthorized: false },
    })

    const channelListHtml = channels
      .map(
        (ch) =>
          `<li><strong>${escapeHtml(ch.name)}</strong> — <code>${escapeHtml(ch.id)}</code>` +
          (ch.country ? ` (${escapeHtml(ch.country)})` : '') +
          (ch.categories.length > 0 ? ` [${ch.categories.map(escapeHtml).join(', ')}]` : '') +
          `</li>`
      )
      .join('\n')

    const subject =
      channels.length === 1
        ? `[Jefflix] Channel Request: ${escapeHtml(channels[0].name)}`
        : `[Jefflix] Channel Request: ${channels.length} channels`

    // Generate approve token for one-click activation
    const approveToken = createApproveToken(
      channels.map((ch) => ({ id: ch.id, name: ch.name })),
      email,
    )
    const baseUrl = process.env.NEXT_PUBLIC_BASE_URL || 'https://jefflix.lol'
    const approveUrl = `${baseUrl}/api/approve-channels?token=${approveToken}`

    await transporter.sendMail({
      from: `Jefflix <${smtpUser}>`,
      to: adminEmail,
      subject,
      html: `
        <h2>New Channel Request</h2>
        <p><strong>${escapeHtml(email)}</strong> requested ${channels.length} channel${channels.length > 1 ? 's' : ''}:</p>

        <div style="text-align: center; margin: 24px 0;">
          <a href="${approveUrl}" style="display: inline-block; background: #22c55e; color: #fff; padding: 14px 32px; border-radius: 8px; text-decoration: none; font-size: 16px; font-weight: 600;">
            &#9989; Approve &amp; Add Channels
          </a>
        </div>
        <p style="text-align: center; color: #888; font-size: 12px;">One click activates these channels in Threadfin and notifies the requester. Link expires in 7 days.</p>

        <ul style="line-height: 1.8;">
          ${channelListHtml}
        </ul>
        <hr style="margin: 20px 0; border: none; border-top: 1px solid #ddd;" />
        <p style="color: #666; font-size: 12px;">Automated message from Jefflix · ${new Date().toLocaleString()}</p>
      `,
    })

    return NextResponse.json({ success: true })
  } catch (error) {
    console.error('Channel request error:', error)
    return NextResponse.json(
      { error: 'Internal server error' },
      { status: 500 }
    )
  }
}

function escapeHtml(text: string): string {
  const map: Record<string, string> = {
    '&': '&amp;',
    '<': '&lt;',
    '>': '&gt;',
    '"': '&quot;',
    "'": '&#039;',
  }
  return text.replace(/[&<>"']/g, (char) => map[char])
}