import { NextRequest, NextResponse } from "next/server";
import { isAuthenticated } from "@/lib/admin-auth";
import { getGenerationStats } from "@/lib/storage";

export async function GET(req: NextRequest) {
  if (!isAuthenticated(req)) {
    return NextResponse.json(
      { error: "Unauthorized. Please login." },
      { status: 401 }
    );
  }

  try {
    const { searchParams } = new URL(req.url);
    const periodParam = searchParams.get("period") as any;
    const rawFromDate = searchParams.get("from") || undefined;
    const rawToDate = searchParams.get("to") || undefined;

    const dateRegex = /^\d{4}-\d{2}-\d{2}$/;
    const fromDate = rawFromDate && dateRegex.test(rawFromDate) ? rawFromDate : undefined;
    const toDate = rawToDate && dateRegex.test(rawToDate) ? rawToDate : undefined;

    const validPeriods = ["day", "week", "month", "all", "custom"];
    const period = validPeriods.includes(periodParam) ? periodParam : "week";

    const stats = getGenerationStats({
      period,
      fromDate,
      toDate,
    });

    return NextResponse.json({
      success: true,
      stats,
    });
  } catch (error: any) {
    console.error("[Portal Stats API] Error:", error);
    return NextResponse.json(
      { success: false, error: "Failed to retrieve statistics" },
      { status: 500 }
    );
  }
}