import { getGameDb } from '@/lib/db/client'
import { MAX_TEAM_SIZE } from '@/lib/game/crew'
import { checkExploreTarget, ExploreError, getSystemState, queueStateFromSave, saveTaskRow } from '@/lib/game/save'
import { queueTask, TaskError } from '@/lib/game/tasks'

// Scan one body of the current system: assign the crew team (lead + helpers) and queue the
// EXPLORE task — the haul, the scanned flag, the crew roll and the event land when the task
// completes on the turn tick (runTurn). Body: { planetId, leadCrewId, helperCrewIds? }.
// Queueing spends no turn; returns the same system snapshot as the instant scan, with the
// findings key empty until the scan resolves (JC-2).
export async function POST(req: Request) {
  let body: unknown
  try {
    body = await req.json()
  } catch {
    return Response.json({ error: 'Invalid JSON body' }, { status: 400 })
  }

  const planetId = (body as { planetId?: unknown }).planetId
  if (typeof planetId !== 'number' || !Number.isInteger(planetId)) {
    return Response.json({ error: 'planetId must be an integer' }, { status: 400 })
  }
  const leadCrewId = (body as { leadCrewId?: unknown }).leadCrewId
  if (typeof leadCrewId !== 'number' || !Number.isInteger(leadCrewId)) {
    return Response.json({ error: 'leadCrewId must be an integer' }, { status: 400 })
  }
  let helperCrewIds: number[] = []
  const rawHelpers = (body as { helperCrewIds?: unknown }).helperCrewIds
  if (rawHelpers !== undefined) {
    if (!Array.isArray(rawHelpers) || !rawHelpers.every((h) => typeof h === 'number' && Number.isInteger(h))) {
      return Response.json({ error: 'helperCrewIds must be an array of integers' }, { status: 400 })
    }
    helperCrewIds = rawHelpers
  }
  // Team rules (route layer, not queueTask's): one task team, distinct members, size cap.
  const team = [leadCrewId, ...helperCrewIds]
  if (new Set(team).size !== team.length) {
    return Response.json({ error: 'crew members must be unique' }, { status: 400 })
  }
  if (team.length > MAX_TEAM_SIZE) {
    return Response.json({ error: `a task team holds at most ${MAX_TEAM_SIZE} crew members` }, { status: 400 })
  }

  try {
    const db = await getGameDb()
    await checkExploreTarget(db, planetId) // existing pre-checks: 404 unknown body · 409 already scanned
    const state = await queueStateFromSave(db)
    const { task } = queueTask(state, { type: 'EXPLORE', payload: { planetId }, leadCrewId, helperCrewIds })
    await saveTaskRow(db, task) // inventory is unchanged until the scan resolves — no hold write
    return Response.json({ ...(await getSystemState(db)), outcome: [], crewFound: null })
  } catch (err) {
    if (err instanceof ExploreError || err instanceof TaskError) {
      return Response.json({ error: err.message }, { status: err.status })
    }
    throw err
  }
}