import { NextResponse, NextRequest } from "next/server";
import { createServiceClient } from "@/lib/supabase";
import { requireAdmin } from "@/lib/admin-auth";

export const dynamic = "force-dynamic";

type DateRange = "today" | "7days" | "30days";

function getDateRange(range: DateRange): { start: string; end: string } {
  const end = new Date();
  const start = new Date();

  switch (range) {
    case "today":
      start.setHours(0, 0, 0, 0);
      break;
    case "7days":
      start.setDate(start.getDate() - 7);
      break;
    case "30days":
      start.setDate(start.getDate() - 30);
      break;
  }

  return {
    start: start.toISOString(),
    end: end.toISOString(),
  };
}

export async function GET(request: NextRequest) {
  // Admin Check
  const check = await requireAdmin();
  if (check instanceof NextResponse) return check;

  const searchParams = request.nextUrl.searchParams;
  const range = (searchParams.get("range") || "today") as DateRange;
  const { start, end } = getDateRange(range);

  try {
    const db = createServiceClient();

    // ─── 1. KPIs: Calls today, trend, unique numbers ────────────────────────

    // Calls today
    const todayStart = new Date();
    todayStart.setHours(0, 0, 0, 0);
    const todayISO = todayStart.toISOString();

    const { count: todayCount } = await db
      .from("phone_clicks")
      .select("*", { count: "exact" })
      .gte("timestamp", todayISO)
      .lte("timestamp", new Date().toISOString());

    const callsToday = todayCount || 0;

    // Calls yesterday for trend
    const yesterdayStart = new Date(todayStart);
    yesterdayStart.setDate(yesterdayStart.getDate() - 1);
    const yesterdayEnd = new Date(yesterdayStart);
    yesterdayEnd.setDate(yesterdayEnd.getDate() + 1);
    const yesterdayISO = yesterdayStart.toISOString();
    const yesterdayEndISO = yesterdayEnd.toISOString();

    const { count: yesterdayCount } = await db
      .from("phone_clicks")
      .select("*", { count: "exact" })
      .gte("timestamp", yesterdayISO)
      .lt("timestamp", yesterdayEndISO);

    const callsYesterday = yesterdayCount || 0;
    const callsTodayTrend =
      callsYesterday > 0
        ? Math.round(((callsToday - callsYesterday) / callsYesterday) * 100)
        : callsToday > 0
          ? 100
          : 0;

    // Unique Numbers
    const { data: uniqueData } = await db
      .from("phone_clicks")
      .select("phone_number")
      .gte("timestamp", start)
      .lte("timestamp", end);

    const uniqueNumbers = new Set(
      (uniqueData || []).map((d) => d.phone_number)
    ).size;

    // Top Number
    const numberCounts: Record<string, number> = {};
    (uniqueData || []).forEach((item) => {
      numberCounts[item.phone_number] =
        (numberCounts[item.phone_number] || 0) + 1;
    });

    const topNumberEntries = Object.entries(numberCounts).sort(
      ([, a], [, b]) => b - a
    );
    const [topNumber, topNumberCount] = topNumberEntries[0] || [null, 0];

    // Top Source Element
    const { data: elementData } = await db
      .from("phone_clicks")
      .select("source_element")
      .gte("timestamp", start)
      .lte("timestamp", end);

    const elementCounts: Record<string, number> = {};
    (elementData || []).forEach((item) => {
      elementCounts[item.source_element] =
        (elementCounts[item.source_element] || 0) + 1;
    });

    const totalClicks = elementData?.length || 0;
    const elementEntries = Object.entries(elementCounts).sort(
      ([, a], [, b]) => b - a
    );
    const [topSourceElement, topSourceElementCount] = elementEntries[0] || [
      null,
      0,
    ];
    const topSourceElementPercent =
      totalClicks > 0
        ? Math.round((topSourceElementCount / totalClicks) * 100)
        : 0;

    // ─── 2. Phone Numbers Table ─────────────────────────────────────────────
    const { data: tableData } = await db
      .from("phone_clicks")
      .select("phone_number, source_page, source_element, country")
      .gte("timestamp", start)
      .lte("timestamp", end);

    const phoneNumbersMap: Record<
      string,
      {
        phone_number: string;
        click_count: number;
        trend_percent: number;
        top_source_page: string;
        top_source_element: string;
        top_country: string;
      }
    > = {};

    (tableData || []).forEach((item) => {
      if (!phoneNumbersMap[item.phone_number]) {
        phoneNumbersMap[item.phone_number] = {
          phone_number: item.phone_number,
          click_count: 0,
          trend_percent: 0,
          top_source_page: "",
          top_source_element: "",
          top_country: item.country || "—",
        };
      }
      phoneNumbersMap[item.phone_number].click_count++;
    });

    const phoneNumbers = Object.values(phoneNumbersMap)
      .sort((a, b) => b.click_count - a.click_count);

    // ─── 3. Element Chart ───────────────────────────────────────────────────
    const elements = Object.entries(elementCounts)
      .map(([element, count]) => ({
        source_element: element,
        count,
        percent: totalClicks > 0 ? Math.round((count / totalClicks) * 100) : 0,
      }))
      .sort((a, b) => b.count - a.count);

    // ─── 4. Timeseries Chart ────────────────────────────────────────────────
    const { data: timeseriesRaw } = await db
      .from("phone_clicks")
      .select("timestamp")
      .gte("timestamp", start)
      .lte("timestamp", end)
      .order("timestamp", { ascending: true });

    const timeseriesMap: Record<string, number> = {};
    (timeseriesRaw || []).forEach((item) => {
      const date = item.timestamp.split("T")[0];
      timeseriesMap[date] = (timeseriesMap[date] || 0) + 1;
    });

    const timeseries = Object.entries(timeseriesMap).map(([date, count]) => ({
      date,
      count,
    }));

    // ─── 5. Geo Chart ───────────────────────────────────────────────────────
    const { data: geoRaw } = await db
      .from("phone_clicks")
      .select("country")
      .gte("timestamp", start)
      .lte("timestamp", end)
      .not("country", "is", null);

    const geoCounts: Record<string, number> = {};
    (geoRaw || []).forEach((item) => {
      if (item.country) {
        geoCounts[item.country] = (geoCounts[item.country] || 0) + 1;
      }
    });

    const geoTotal = geoRaw?.length || 0;
    const geo = Object.entries(geoCounts)
      .map(([country, count]) => ({
        country,
        count,
        percent: geoTotal > 0 ? Math.round((count / geoTotal) * 100) : 0,
      }))
      .sort((a, b) => b.count - a.count)
      .slice(0, 10);

    return NextResponse.json({
      kpis: {
        callsToday,
        callsTodayTrend,
        uniqueNumbers,
        topNumber,
        topNumberCount,
        topSourceElement,
        topSourceElementPercent,
      },
      phoneNumbers,
      elements,
      timeseries,
      geo,
    });
  } catch (error) {
    console.error("Phone calls analytics error:", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500 }
    );
  }
}