import { newId } from "@fetcha/core";
import { abuseEvents, db } from "@fetcha/db";
import { getEmailService } from "@fetcha/email";
import type { ApiPrincipal } from "../auth";
import type { MonthlyUsage } from "../limits";
import { getKV } from "../redis";
import { formatUsd } from "./pricing";

function monthKey(): string {
  const d = new Date();
  return `${d.getUTCFullYear()}-${String(d.getUTCMonth() + 1).padStart(2, "0")}`;
}

/** Send soft-limit alerts once per project/org per month (idempotent via KV flags). */
export async function checkSpendAlerts(p: ApiPrincipal, usage: MonthlyUsage): Promise<void> {
  const kv = getKV();
  const email = getEmailService();
  const checks: Array<{ key: string; spent: number; limit: number | null; label: string }> = [
    { key: `fch:alert:soft:proj:${p.projectId}:${monthKey()}`, spent: usage.projectSpendUsd, limit: p.projectSoftLimitUsd, label: p.projectName },
    { key: `fch:alert:soft:org:${p.organizationId}:${monthKey()}`, spent: usage.spendUsd, limit: p.orgSoftLimitUsd, label: p.organizationName },
  ];
  for (const c of checks) {
    if (c.limit === null || c.limit <= 0 || c.spent < c.limit) continue;
    if (await kv.get(c.key).catch(() => "1")) continue;
    await kv.set(c.key, "1", 40 * 86_400).catch(() => {});
    email.sendUsageAlert(p.ownerEmail, { projectName: c.label, spent: formatUsd(c.spent), limit: formatUsd(c.limit), kind: "soft" }).catch(() => {});
  }
}

/** Notify once per month when a hard limit blocks requests. */
export async function notifyHardLimit(p: ApiPrincipal, usage: MonthlyUsage): Promise<void> {
  const kv = getKV();
  const key = `fch:alert:hard:${p.projectId}:${monthKey()}`;
  if (await kv.get(key).catch(() => "1")) return;
  await kv.set(key, "1", 40 * 86_400).catch(() => {});
  const limit = p.projectHardLimitUsd ?? p.orgHardLimitUsd ?? 0;
  getEmailService()
    .sendUsageAlert(p.ownerEmail, { projectName: p.projectName, spent: formatUsd(Math.max(usage.projectSpendUsd, usage.spendUsd)), limit: formatUsd(limit), kind: "hard" })
    .catch(() => {});
}

/** Record an abuse signal (SSRF attempt, prohibited target…) for admin review. */
export async function recordAbuse(p: ApiPrincipal, requestId: string, kind: "ssrf_attempt" | "prohibited_target" | "rate_abuse", detail: string): Promise<void> {
  await db
    .insert(abuseEvents)
    .values({ id: newId("abuse"), organizationId: p.organizationId, projectId: p.projectId, requestId, kind, severity: kind === "ssrf_attempt" ? "medium" : "low", detail: detail.slice(0, 500) })
    .catch(() => {});
}