import { NextRequest, NextResponse } from 'next/server'
import pool from '@/lib/db'

// GET /api/sales/[id] - Get a specific sale
export async function GET(
  request: NextRequest,
  { params }: { params: { id: string } }
) {
  try {
    const id = parseInt(params.id, 10)
    if (isNaN(id)) {
      return NextResponse.json(
        { error: 'Invalid sale ID' },
        { status: 400 }
      )
    }

    const [rows] = await pool.execute(
      `SELECT 
        s.id,
        s.drop_id,
        s.buyer_id,
        s.size,
        s.payment_id,
        s.created_at,
        d.item as drop_item,
        d.unit as drop_unit,
        d.ppu as drop_ppu,
        b.username as buyer_username,
        b.email as buyer_email
      FROM sales s
      LEFT JOIN drops d ON s.drop_id = d.id
      LEFT JOIN buyers b ON s.buyer_id = b.id
      WHERE s.id = ?`,
      [id]
    )

    const sales = rows as any[]
    if (sales.length === 0) {
      return NextResponse.json(
        { error: 'Sale not found' },
        { status: 404 }
      )
    }

    return NextResponse.json(sales[0])
  } catch (error) {
    console.error('Error fetching sale:', error)
    return NextResponse.json(
      { error: 'Failed to fetch sale' },
      { status: 500 }
    )
  }
}

// PUT /api/sales/[id] - Update a sale
export async function PUT(
  request: NextRequest,
  { params }: { params: { id: string } }
) {
  try {
    const id = parseInt(params.id, 10)
    if (isNaN(id)) {
      return NextResponse.json(
        { error: 'Invalid sale ID' },
        { status: 400 }
      )
    }

    const body = await request.json()
    const { drop_id, buyer_id, size, payment_id } = body

    // Check if sale exists
    const [existingRows] = await pool.execute(
      'SELECT id FROM sales WHERE id = ?',
      [id]
    )
    const existing = existingRows as any[]
    if (existing.length === 0) {
      return NextResponse.json(
        { error: 'Sale not found' },
        { status: 404 }
      )
    }

    // Build update query dynamically
    const updates: string[] = []
    const values: any[] = []

    if (drop_id !== undefined) {
      // Verify drop exists
      const [dropCheck] = await pool.execute(
        'SELECT id FROM drops WHERE id = ?',
        [drop_id]
      )
      if ((dropCheck as any[]).length === 0) {
        return NextResponse.json(
          { error: 'Drop not found' },
          { status: 400 }
        )
      }
      updates.push('drop_id = ?')
      values.push(drop_id)
    }

    if (buyer_id !== undefined) {
      // Verify buyer exists
      const [buyerCheck] = await pool.execute(
        'SELECT id FROM buyers WHERE id = ?',
        [buyer_id]
      )
      if ((buyerCheck as any[]).length === 0) {
        return NextResponse.json(
          { error: 'Buyer not found' },
          { status: 400 }
        )
      }
      updates.push('buyer_id = ?')
      values.push(buyer_id)
    }

    if (size !== undefined) {
      if (size <= 0) {
        return NextResponse.json(
          { error: 'Size must be greater than 0' },
          { status: 400 }
        )
      }
      updates.push('size = ?')
      values.push(size)
    }

    if (payment_id !== undefined) {
      updates.push('payment_id = ?')
      values.push(payment_id)
    }

    if (updates.length === 0) {
      return NextResponse.json(
        { error: 'No fields to update' },
        { status: 400 }
      )
    }

    values.push(id)
    const query = `UPDATE sales SET ${updates.join(', ')} WHERE id = ?`
    await pool.execute(query, values)

    // Fetch updated sale
    const [rows] = await pool.execute(
      `SELECT 
        s.id,
        s.drop_id,
        s.buyer_id,
        s.size,
        s.payment_id,
        s.created_at,
        d.item as drop_item,
        d.unit as drop_unit,
        d.ppu as drop_ppu,
        b.username as buyer_username,
        b.email as buyer_email
      FROM sales s
      LEFT JOIN drops d ON s.drop_id = d.id
      LEFT JOIN buyers b ON s.buyer_id = b.id
      WHERE s.id = ?`,
      [id]
    )

    return NextResponse.json((rows as any[])[0])
  } catch (error) {
    console.error('Error updating sale:', error)
    return NextResponse.json(
      { error: 'Failed to update sale' },
      { status: 500 }
    )
  }
}

// DELETE /api/sales/[id] - Delete a sale
export async function DELETE(
  request: NextRequest,
  { params }: { params: { id: string } }
) {
  try {
    const id = parseInt(params.id, 10)
    if (isNaN(id)) {
      return NextResponse.json(
        { error: 'Invalid sale ID' },
        { status: 400 }
      )
    }

    // Check if sale exists
    const [existingRows] = await pool.execute(
      'SELECT id FROM sales WHERE id = ?',
      [id]
    )
    const existing = existingRows as any[]
    if (existing.length === 0) {
      return NextResponse.json(
        { error: 'Sale not found' },
        { status: 404 }
      )
    }

    // Delete sale
    await pool.execute('DELETE FROM sales WHERE id = ?', [id])

    return NextResponse.json({ success: true })
  } catch (error) {
    console.error('Error deleting sale:', error)
    return NextResponse.json(
      { error: 'Failed to delete sale' },
      { status: 500 }
    )
  }
}