import type {
  FlightReportRequest,
  FlightSearchPlan,
  FlightSearchSourceFinding,
  FlightSearchSourceName,
  FlightSearchSourceViability
} from "./types.js";

export const SOURCE_SILENT_TIMEOUT_MS = 45_000;
export const SOURCE_TOTAL_TIMEOUT_MS = 180_000;
export const RUN_TOTAL_TIMEOUT_MS = 900_000;
export const VPN_CONNECT_TIMEOUT_MS = 30_000;
export const VPN_DISCONNECT_TIMEOUT_MS = 15_000;

const DEFAULT_SOURCE_ORDER: FlightSearchSourceName[] = [
  "kayak",
  "skyscanner",
  "expedia",
  "airline-direct"
];

function findingFor(
  source: FlightSearchSourceName,
  findings: FlightSearchSourceFinding[]
): FlightSearchSourceFinding | undefined {
  return findings.find((entry) => entry.source === source);
}

function sourceStatus(
  source: FlightSearchSourceName,
  findings: FlightSearchSourceFinding[]
): FlightSearchSourceViability {
  return findingFor(source, findings)?.status || "viable";
}

export function buildFlightSearchPlan(
  request: FlightReportRequest,
  findings: FlightSearchSourceFinding[] = []
): FlightSearchPlan {
  const sourceOrder = DEFAULT_SOURCE_ORDER.map((source) => {
    const status = sourceStatus(source, findings);
    const finding = findingFor(source, findings);
    const required = source !== "airline-direct";
    const enabled = status !== "blocked";
    const reason =
      finding?.notes[0] ||
      (source === "airline-direct"
        ? "Best-effort airline direct cross-check."
        : "Primary bounded search source.");

    return {
      source,
      enabled,
      required,
      status,
      silentTimeoutMs: SOURCE_SILENT_TIMEOUT_MS,
      totalTimeoutMs: SOURCE_TOTAL_TIMEOUT_MS,
      reason
    };
  });

  const degradedReasons = sourceOrder
    .filter((source) => source.status !== "viable")
    .map((source) =>
      source.enabled
        ? `${source.source} is degraded for this run: ${source.reason}`
        : `${source.source} is blocked for this run: ${source.reason}`
    );

  return {
    sourceOrder,
    vpn: {
      enabled: Boolean(request.preferences.marketCountry),
      marketCountry: request.preferences.marketCountry || null,
      connectTimeoutMs: VPN_CONNECT_TIMEOUT_MS,
      disconnectTimeoutMs: VPN_DISCONNECT_TIMEOUT_MS,
      fallbackMode: "default-market"
    },
    degradedReasons
  };
}