import { ref, computed } from 'vue'
import type { DefensiveDecision } from '~/types/game'

// Module-level singleton state (shared across all consumers)
const holdRunners = ref<Set<number>>(new Set())
const infieldDepth = ref<'infield_in' | 'normal' | 'corners_in'>('normal')
const outfieldDepth = ref<'normal' | 'shallow'>('normal')

export function useDefensiveSetup() {
  /** Reactive array of held base numbers (for prop passing) */
  const holdRunnersArray = computed<number[]>(() => Array.from(holdRunners.value).sort())

  /** Check if a specific base is held */
  function isHeld(base: number): boolean {
    return holdRunners.value.has(base)
  }

  /** Toggle hold on a base (1, 2, or 3) */
  function toggleHold(base: number) {
    const next = new Set(holdRunners.value)
    if (next.has(base)) {
      next.delete(base)
    } else {
      next.add(base)
    }
    holdRunners.value = next
  }

  /** Reset all defensive setup to defaults */
  function reset() {
    holdRunners.value = new Set()
    infieldDepth.value = 'normal'
    outfieldDepth.value = 'normal'
  }

  /** Sync state from an existing DefensiveDecision (e.g. from props/server) */
  function syncFromDecision(decision: DefensiveDecision) {
    holdRunners.value = new Set(decision.hold_runners)
    infieldDepth.value = decision.infield_depth
    outfieldDepth.value = decision.outfield_depth
  }

  /** Build a DefensiveDecision from current working state */
  function getDecision(): DefensiveDecision {
    return {
      infield_depth: infieldDepth.value,
      outfield_depth: outfieldDepth.value,
      hold_runners: holdRunnersArray.value,
    }
  }

  return {
    holdRunners,
    holdRunnersArray,
    infieldDepth,
    outfieldDepth,
    isHeld,
    toggleHold,
    reset,
    syncFromDecision,
    getDecision,
  }
}