import { NextResponse } from "next/server"
import { and, eq } from "drizzle-orm"
import { db } from "@/lib/db"
import { properties, maintenance_requests } from "@/lib/db/schema"
import { getSessionUser } from "@/lib/session"
import { getEffectiveOwnerId } from "@/lib/account"
import { aiConfigured, AI_UNCONFIGURED_ERROR } from "@/lib/ai/client"
import { aiComplete } from "@/lib/ai/provider"
import { MAINTENANCE_SUMMARY_PROMPT, dataBlock } from "@/lib/ai/prompts"
import { enforceAiQuota } from "@/lib/ai/usage"

export async function POST(request: Request) {
  const user = await getSessionUser()
  if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })

  // Before the quota check so an unconfigured server never burns a call.
  if (!aiConfigured()) return NextResponse.json({ error: AI_UNCONFIGURED_ERROR }, { status: 503 })

  const quota = await enforceAiQuota(user.id, "ai_maintenance_summary")
  if (!quota.ok) return NextResponse.json({ error: quota.error }, { status: quota.status })

  const ownerId = await getEffectiveOwnerId(user.id)

  const { property_id } = await request.json() as { property_id: string }

  const requests = await db
    .select({
      title: maintenance_requests.title,
      description: maintenance_requests.description,
      category: maintenance_requests.category,
      priority: maintenance_requests.priority,
      status: maintenance_requests.status,
      estimated_cost: maintenance_requests.estimated_cost,
      actual_cost: maintenance_requests.actual_cost,
      created_at: maintenance_requests.created_at,
      resolved_at: maintenance_requests.resolved_at,
    })
    .from(maintenance_requests)
    .where(and(eq(maintenance_requests.user_id, ownerId), eq(maintenance_requests.property_id, property_id)))

  const property = await db.query.properties.findFirst({
    where: and(eq(properties.id, property_id), eq(properties.user_id, ownerId)),
    columns: { name: true },
  })

  const text = await aiComplete({
    messages: [
      { role: "system", content: MAINTENANCE_SUMMARY_PROMPT },
      {
        role: "user",
        content: `${dataBlock("PROPERTY NAME", property?.name ?? "Unknown")}\n\n${dataBlock("MAINTENANCE REQUESTS", JSON.stringify(requests, null, 2))}`,
      },
    ],
    maxTokens: 1024,
    json: true,
  })

  let summary
  try {
    summary = JSON.parse(text)
  } catch {
    return NextResponse.json({ error: "Failed to parse AI response" }, { status: 500 })
  }

  return NextResponse.json(summary)
}
