/**
 * apps/worker — SEND_EMAIL executor (TASK-0112 §7/§8).
 *
 * Resolve the recipient (`to`: literal email | trigger_user |
 * automation_creator → the User's email; a missing/invalid address → fatal
 * EMAIL_ADDRESS_MISSING), reserve the daily cap slot (fatal EMAIL_DAILY_CAP),
 * interpolate subject + markdown→HTML body, and enqueue the email job on the
 * email queue with a STABLE job id (`automation-email:{runId}:{i}`) so a
 * run-retry never double-sends. CC is a literal email list (max 5, schema).
 */
import { renderMarkdown } from "@factory/shared";
import { enqueue, QUEUES } from "../../../queues.js";
import { FatalError } from "./classify.js";
import { reserveEmailSlot } from "./email-cap.js";
import { interpolateConfig, resolveUserId } from "./helpers.js";
import type { ActionExecutor, ActionResult } from "./types.js";

/**
 * @param index the action's position in the run (for the stable job id).
 */
export async function sendEmail(
  cfg: Record<string, unknown>,
  ctx: import("./types.js").AutomationRunContext,
  deps: import("./types.js").ExecutorDeps,
  index: number
): Promise<ActionResult> {
  const warnings: string[] = [];
  const toRaw = (cfg.to as string) ?? "automation_creator";
  let toEmail: string;
  if (toRaw === "trigger_user" || toRaw === "automation_creator") {
    const userId = resolveUserId(toRaw, ctx);
    const user = await deps.prisma.user.findUnique({ where: { id: userId }, select: { email: true } });
    if (!user?.email) throw new FatalError("EMAIL_ADDRESS_MISSING", `recipient ${toRaw} has no email address`);
    toEmail = user.email;
  } else {
    toEmail = toRaw; // literal (validated as an email at save time)
  }

  const cc = Array.isArray(cfg.cc) ? (cfg.cc as string[]) : [];
  const subject = interpolateConfig(cfg.subject as string, ctx.vars, 200, "subject", warnings);
  const bodyHtml = interpolateConfig(cfg.body as string, ctx.vars, 20_000, "body", warnings);

  // Reserve the daily slot BEFORE enqueueing (the enqueue is the commit).
  await reserveEmailSlot(deps.redis, ctx.workspaceId);

  await enqueue(
    deps.redis,
    QUEUES.email,
    { to: toEmail, cc, subject, html: renderMarkdown(bodyHtml), text: bodyHtml, template: "automation" },
    { jobId: `automation-email:${ctx.runId}:${index}` }
  );

  return {
    output: { to: toEmail, cc, subject, slotReserved: true },
    emittedEvents: [],
    audit: { action: "automation.email_sent", resourceType: "user", resourceId: toEmail, metadata: { cc } }
  };
}

const executor: ActionExecutor = {
  type: "SEND_EMAIL",
  execute: (cfg, ctx, deps, index) => sendEmail(cfg, ctx, deps, index ?? 0)
};

export default executor;