import type { NextApiRequest, NextApiResponse } from "next"
import { db, schema } from '../../../lib/db/connection'
import { eq, and, desc, count } from 'drizzle-orm'

export default async function handler(req: NextApiRequest, res: NextApiResponse) {
  if (req.method !== "GET") return res.status(405).json({ error: "Method not allowed" })
  
  const { page = '1', limit = '50', action, resource_type, user_id } = req.query
  
  try {
    let whereConditions = []
    
    if (action) {
      whereConditions.push(eq(schema.auditLogs.action, action as string))
    }
    
    if (resource_type) {
      whereConditions.push(eq(schema.auditLogs.resourceType, resource_type as string))
    }
    
    if (user_id) {
      whereConditions.push(eq(schema.auditLogs.userId, parseInt(user_id as string)))
    }
    
    const offset = (parseInt(page as string) - 1) * parseInt(limit as string)
    const limitInt = parseInt(limit as string)
    
    // Get logs with user info
    const logs = await db
      .select({
        id: schema.auditLogs.id,
        userId: schema.auditLogs.userId,
        userEmail: schema.users.email,
        action: schema.auditLogs.action,
        resourceType: schema.auditLogs.resourceType,
        resourceId: schema.auditLogs.resourceId,
        details: schema.auditLogs.details,
        ipAddress: schema.auditLogs.ipAddress,
        createdAt: schema.auditLogs.createdAt
      })
      .from(schema.auditLogs)
      .leftJoin(schema.users, eq(schema.auditLogs.userId, schema.users.id))
      .where(whereConditions.length > 0 ? and(...whereConditions) : undefined)
      .orderBy(desc(schema.auditLogs.createdAt))
      .limit(limitInt)
      .offset(offset)
    
    // Get total count for pagination
    const [totalResult] = await db
      .select({ count: count() })
      .from(schema.auditLogs)
      .where(whereConditions.length > 0 ? and(...whereConditions) : undefined)
    
    const total = totalResult.count
    const totalPages = Math.ceil(total / limitInt)
    
    res.json({
      logs: logs.map(log => ({
        id: log.id,
        user_id: log.userId,
        user_email: log.userEmail,
        action: log.action,
        resource_type: log.resourceType,
        resource_id: log.resourceId,
        details: log.details ? JSON.parse(log.details) : null,
        ip_address: log.ipAddress,
        created_at: log.createdAt
      })),
      pagination: {
        page: parseInt(page as string),
        limit: limitInt,
        total,
        totalPages
      }
    })
    
  } catch (error) {
    console.error('Audit logs error:', error)
    res.status(500).json({ error: "Failed to fetch audit logs" })
  }
}