import { getGameDb } from '@/lib/db/client'
import * as schema from '@/lib/db/schema'
import { parseCrewTeam } from '@/app/api/crew-team'
import { checkBuildPreconditions, getShipState, ShipError } from '@/lib/game/ship'
import { makePowerOfFor, queueStateFromSave, saveInventory, saveTaskRow } from '@/lib/game/save'
import { queueTask, TaskError } from '@/lib/game/tasks'

// Build an unbuilt ship system type at base values: assign the crew team (lead + helpers)
// and queue the SHIP_BUILD task — the flat parts cost is deducted at queue time and the
// build lands when the task completes on the turn tick (runTurn). Body:
// { type, leadCrewId, helperCrewIds? }. Queueing spends no turn; returns the same fresh
// ship state the instant action returned.
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 type = (body as { type?: unknown }).type
  if (typeof type !== 'string' || type.length === 0) {
    return Response.json({ error: 'type must be a non-empty string' }, { status: 400 })
  }
  const team = parseCrewTeam(body)
  if ('error' in team) {
    return Response.json({ error: team.error }, { status: team.status })
  }

  try {
    const db = await getGameDb()
    await checkBuildPreconditions(db, type) // existing pre-checks: 404 unknown type · 409 already built / build gate
    const state = await queueStateFromSave(db)
    const [save] = await db.db.select().from(schema.saves).limit(1)
    const { task, inventory } = queueTask(state, { type: 'SHIP_BUILD', payload: { type }, leadCrewId: team.leadCrewId, helperCrewIds: team.helperCrewIds }, await makePowerOfFor(db, save, 'SHIP_BUILD'))
    await saveTaskRow(db, task)
    await saveInventory(db, inventory) // the cost was deducted at queue time
    return Response.json(await getShipState(db))
  } catch (err) {
    if (err instanceof ShipError || err instanceof TaskError) {
      return Response.json({ error: err.message }, { status: err.status })
    }
    throw err
  }
}