/**
 * Processor for "ddma-claim-submit" jobs.
 * Opens a claim on the Delta Dental MA provider portal via Selenium.
 *
 * Flow:
 *   1. POST /ddma-claim to Python agent → get session_id
 *   2. Emit selenium:ddma_claim_started to frontend
 *   3. Poll until completed/error
 *   4. Emit result
 */
import {
  forwardToSeleniumDDMAClaimAgent,
  getSeleniumDDMAClaimSessionStatus,
} from "../../services/seleniumDDMAClaimClient";
import { io } from "../../socket";
import { storage } from "../../storage";
import axios from "axios";
import path from "path";

function log(tag: string, msg: string, ctx?: any) {
  console.log(`${new Date().toISOString()} [${tag}] ${msg}`, ctx ?? "");
}

function emitToSocket(socketId: string | undefined, event: string, payload: any) {
  if (!socketId || !io) return;
  try {
    const socket = io.sockets.sockets.get(socketId);
    if (socket) socket.emit(event, payload);
  } catch (_) {}
}

async function pollUntilDone(
  sessionId: string,
  socketId: string | undefined,
  jobId: string,
  pollTimeoutMs = 10 * 60 * 1000
): Promise<any> {
  const maxAttempts = 1200;
  const pollIntervalMs = 500;
  const maxTransientErrors = 12;
  let transientErrors = 0;
  let lastOtpEmit = 0;
  const deadline = Date.now() + pollTimeoutMs;

  for (let attempt = 0; attempt < maxAttempts; attempt++) {
    if (Date.now() > deadline) {
      throw new Error(`DDMA claim polling timeout for session ${sessionId}`);
    }
    try {
      const st = await getSeleniumDDMAClaimSessionStatus(sessionId);
      const status: string = st?.status ?? "unknown";
      log("ddma-claim-processor", `poll attempt=${attempt}`, { sessionId, status });
      transientErrors = 0;

      if (status === "waiting_for_otp") {
        // Throttle: emit at most once every 5 s so the frontend isn't flooded
        if (Date.now() - lastOtpEmit > 5000) {
          emitToSocket(socketId, "selenium:otp_required", {
            session_id: sessionId,
            jobId,
            message: "OTP required. Please enter the OTP shown by the DDMA portal.",
          });
          lastOtpEmit = Date.now();
        }
        await new Promise((r) => setTimeout(r, pollIntervalMs));
        continue;
      }

      if (status === "completed") return st.result;
      if (status === "error" || status === "not_found") {
        throw new Error(st?.message || `DDMA claim session ended with status: ${status}`);
      }
      await new Promise((r) => setTimeout(r, pollIntervalMs));
    } catch (err: any) {
      const isTerminal =
        err?.response?.status === 404 ||
        (typeof err?.message === "string" &&
          (err.message.includes("not_found") || err.message.includes("polling timeout")));
      if (isTerminal) throw err;
      transientErrors++;
      if (transientErrors > maxTransientErrors) {
        throw new Error(`Too many transient errors polling DDMA claim session ${sessionId}`);
      }
      const backoff = Math.min(30_000, 500 * Math.pow(2, transientErrors - 1));
      await new Promise((r) => setTimeout(r, backoff));
    }
  }
  throw new Error(`DDMA claim polling exhausted all attempts for session ${sessionId}`);
}

async function savePdfFromSelenium(pdf_url: string, patientId: number) {
  try {
    const filename = path.basename(new URL(pdf_url).pathname);
    const seleniumPort = process.env.SELENIUM_PORT || "5002";
    const localUrl = `http://localhost:${seleniumPort}/downloads/${filename}`;
    const resp = await axios.get(localUrl, { responseType: "arraybuffer", timeout: 30000 });
    let group = await storage.findPdfGroupByPatientTitleKey(patientId, "INSURANCE_CLAIM");
    if (!group) group = await storage.createPdfGroup(patientId, "Claims", "INSURANCE_CLAIM");
    await storage.createPdfFile(group.id!, filename, resp.data);
    log("ddma-claim-processor", "PDF saved", { patientId, filename });
  } catch (err: any) {
    log("ddma-claim-processor", "failed to save PDF (non-fatal)", { error: err?.message ?? err });
  }
}

export interface DDMAClaimProcessorInput {
  enrichedPayload: any;
  userId: number;
  claimId?: number;
  socketId?: string;
}

export async function runDDMAClaimProcessor(
  input: DDMAClaimProcessorInput,
  jobId: string
): Promise<{ status: string; pdf_url?: string; claimNumber?: string }> {
  const { enrichedPayload, userId, claimId, socketId } = input;

  log("ddma-claim-processor", "starting Python agent session", { claimId });
  const agentResp = await forwardToSeleniumDDMAClaimAgent(enrichedPayload);

  if (!agentResp?.session_id) {
    throw new Error("Python agent did not return a session_id for DDMA claim");
  }

  const sessionId = agentResp.session_id as string;
  log("ddma-claim-processor", "got session_id", { sessionId });

  emitToSocket(socketId, "selenium:ddma_claim_started", { session_id: sessionId, jobId });

  const seleniumResult = await pollUntilDone(sessionId, socketId, jobId);

  if (!seleniumResult || seleniumResult.status === "error") {
    throw new Error(seleniumResult?.message ?? "DDMA claim session returned an error");
  }

  const claimNumber: string | undefined = seleniumResult.claimNumber ?? undefined;
  const pdf_url: string | undefined = seleniumResult.pdf_url ?? undefined;

  // Persist claim number and update status
  if (claimId) {
    try {
      const updates: Record<string, any> = { status: "REVIEW" };
      if (claimNumber) updates.claimNumber = claimNumber;
      await storage.updateClaim(claimId, updates);
      log("ddma-claim-processor", "claim record updated", { claimId, claimNumber });

      // Touch patient so they rise to top of the list across all pages
      const claim = await storage.getClaim(claimId);
      if (claim?.patientId) {
        await storage.touchPatient(claim.patientId);
        log("ddma-claim-processor", "patient touched", { patientId: claim.patientId });
      }
    } catch (e) {
      log("ddma-claim-processor", "failed to update claim record (non-fatal)", { error: e });
    }
  }

  // Auto-save PDF for batch-column calls (no socketId = no frontend listener)
  if (pdf_url && !socketId) {
    const claim = claimId ? await storage.getClaim(claimId).catch(() => null) : null;
    const patientId = claim?.patientId ?? enrichedPayload?.claim?.patientId ?? enrichedPayload?.patientId;
    if (patientId) await savePdfFromSelenium(pdf_url, Number(patientId));
  }

  emitToSocket(socketId, "selenium:ddma_claim_completed", {
    jobId,
    claimId,
    claimNumber,
    pdf_url,
    message: claimNumber
      ? `DDMA claim submitted — Claim #: ${claimNumber}`
      : (seleniumResult?.message ?? "DDMA claim submitted successfully"),
  });

  log("ddma-claim-processor", "done", { claimId, claimNumber });
  return { status: "success", pdf_url, claimNumber };
}
