import { NextResponse } from "next/server";
import { eq } from "drizzle-orm";
import { auth } from "@/app/(auth)/auth";
import { db } from "@/lib/db";
import { systemSettings } from "@/lib/db/schema";
import {
  getPointsLedgerByUserId,
  getPointsSystemConfig,
  getUserById,
} from "@/lib/db/queries";
import {
  defaultMembershipConfig,
  defaultMembershipUserOverrides,
  getMembershipPlanById,
  normalizeMembershipConfig,
  normalizeMembershipUserOverrides,
  resolveMembershipPlanIdForUser,
} from "@/lib/membership/config";

const MEMBERSHIP_CONFIG_KEY = "membership_config";
const MEMBERSHIP_USER_OVERRIDES_KEY = "membership_user_plan_overrides";

function mapLedgerReasonLabel(reason: string) {
  if (reason === "image_generation") return "图片生成";
  if (reason === "gift") return "管理员赠送";
  if (reason === "recharge") return "积分充值";
  if (reason === "adjust") return "积分调整";
  return reason || "积分变动";
}

export async function GET() {
  try {
    const session = await auth();
    if (!session?.user?.id) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const [dbUser, pointsConfig, ledger, configSetting, overridesSetting] =
      await Promise.all([
        getUserById({ id: session.user.id }),
        getPointsSystemConfig(),
        getPointsLedgerByUserId({ userId: session.user.id, limit: 200 }),
        db
          .select()
          .from(systemSettings)
          .where(eq(systemSettings.key, MEMBERSHIP_CONFIG_KEY))
          .limit(1)
          .then((rows) => rows[0]),
        db
          .select()
          .from(systemSettings)
          .where(eq(systemSettings.key, MEMBERSHIP_USER_OVERRIDES_KEY))
          .limit(1)
          .then((rows) => rows[0]),
      ]);

    const membershipConfig = configSetting?.value
      ? normalizeMembershipConfig(configSetting.value)
      : defaultMembershipConfig;
    const membershipOverrides = overridesSetting?.value
      ? normalizeMembershipUserOverrides(overridesSetting.value)
      : defaultMembershipUserOverrides;
    const currentPlanId = resolveMembershipPlanIdForUser(
      session.user.id,
      session.user.email,
      membershipConfig,
      membershipOverrides
    );
    const currentPlan = getMembershipPlanById(membershipConfig, currentPlanId);

    const usageRecords = ledger.map((item) => ({
      id: item.id,
      detail: item.note || mapLedgerReasonLabel(item.reason),
      status: item.amount < 0 ? "consumed" : "earned",
      amount: item.amount,
      createdAt: item.createdAt?.toISOString() || new Date().toISOString(),
    }));

    const billingRecords = ledger
      .filter((item) => item.reason === "recharge" || item.reason === "gift")
      .map((item) => ({
        id: item.id,
        date: item.createdAt?.toISOString() || new Date().toISOString(),
        category: item.reason === "recharge" ? "积分充值" : "积分赠送",
        amount: item.amount,
        status: "completed",
        invoice: "-",
      }));

    return NextResponse.json({
      profile: {
        name: dbUser?.name || session.user.name || "",
        email: dbUser?.email || session.user.email || "",
        currentPlanName: currentPlan.name,
        currentPlanId,
        availablePoints: pointsConfig.enabled
          ? Math.max(0, Number(dbUser?.pointsBalance || 0))
          : currentPlan.monthlyCredits,
        monthlyCredits: currentPlan.monthlyCredits,
        dailyFreeCredits: currentPlan.dailyFreeCredits,
      },
      usageRecords,
      billingRecords,
    });
  } catch (error) {
    console.error("[Account Center API] Error:", error);
    return NextResponse.json(
      { error: "Failed to fetch account center data" },
      { status: 500 }
    );
  }
}