import { content } from "@deadhead/content";
import type { SaveDocument } from "@deadhead/schema";
import {
  boardPeriodIndex,
  canLandAt,
  emergencyFuel,
  isInShop,
  permanentFailure,
  shipStats,
  tripFuel,
  type AwayProblem,
  type RealTime,
} from "@deadhead/sim";
import { acceptedContractIds } from "./boards";
import { discoveredIds, shipState } from "./state";
import { canReachBooking } from "./service";

/**
 * What needs the player now (decision 0.5.140's last highlight), from the
 * state: idle crewed ships that can't fly anywhere on the fuel aboard (or need
 * emergency fuel), Manual ships whose board this period has no job they could
 * take, credits below the pilots' spending floor, and booked service waiting
 * for funds or out of reach (CR-027).
 */
export function awayProblems(save: SaveDocument, now: RealTime): AwayProblem[] {
  if (save.player.tutorialActive) return [];
  const discovered = discoveredIds(save);
  const accepted = acceptedContractIds(save);
  const period = boardPeriodIndex(now, content.config);
  const problems: AwayProblem[] = [];
  // Booked service stuck (CR-027 §4): waiting for funds, or the HQ out of reach.
  for (const ship of save.ships) {
    const booking = ship.booking;
    if (!booking || booking.startedAt !== null) continue;
    if (booking.waitingSince !== null) {
      problems.push({ kind: "service-waiting-funds", shipId: ship.id, hqId: booking.hqId });
    } else if (!canReachBooking(save, ship)) {
      problems.push({ kind: "service-cant-reach", shipId: ship.id, hqId: booking.hqId });
    }
  }
  for (const ship of save.ships) {
    const pilot = save.pilots.find((p) => p.assignedShipId === ship.id);
    if (ship.status !== "idle" || !ship.locationId || !pilot || isInShop(ship, now)) continue;
    const at = { shipId: ship.id, locationId: ship.locationId };
    const state = shipState(ship);
    if (
      emergencyFuel(
        { ship: state, credits: save.company.credits, discoveredIds: discovered },
        content,
      )
    ) {
      problems.push({ kind: "emergency-fuel", ...at });
      continue;
    }
    const model = shipStats(state, content);
    const here = content.location(ship.locationId)!;
    const legs = content.locations
      .filter((next) => next.id !== here.id && discovered.has(next.id) && canLandAt(model, next))
      .map((next) => tripFuel(model, here, next, content.config));
    if (legs.length > 0 && Math.min(...legs) > ship.fuelFu) {
      problems.push({ kind: "low-fuel", ...at });
      continue;
    }
    // Only the player sends a Manual pilot; an Independent one waits or heads home.
    if (pilot.mode !== "manual") continue;
    const board = save.contractBoards.find(
      (b) => b.kind === "location" && b.locationId === ship.locationId && b.periodIndex === period,
    );
    if (!board) continue;
    const member = {
      modelId: ship.modelId,
      skills: pilot.skills,
      upgrades: ship.upgrades,
      fuelFu: ship.fuelFu,
    };
    const open = board.contracts.filter((c) => !accepted.has(c.id) && c.expiresAt > now);
    if (!open.some((c) => permanentFailure(c, member, discovered, content) === null)) {
      problems.push({ kind: "no-jobs", ...at });
    }
  }
  const { credits, npcSpendingFloor, dispatchOffice } = save.company;
  if (
    dispatchOffice &&
    credits < npcSpendingFloor &&
    save.pilots.some((p) => p.mode === "independent")
  ) {
    problems.push({ kind: "below-floor", credits, floor: npcSpendingFloor });
  }
  return problems;
}