import type { GameAction } from './types'
import { stateManager } from './StateManager'

/** All state mutations go through an adapter.
 *  Swap LocalAdapter for WebSocketAdapter to enable multiplayer. */
export interface NetworkAdapter {
  send(action: GameAction): void
  onAction?: (action: GameAction) => void
}

const ACTION_LOG_SIZE = 15

/** Singleplayer: apply actions immediately and synchronously */
export class LocalAdapter implements NetworkAdapter {
  onAction?: (action: GameAction) => void

  /** Ring-buffer of the last ACTION_LOG_SIZE dispatched action summaries. */
  private _actionLog: string[] = []

  send(action: GameAction): void {
    stateManager.apply(action)
    this._recordAction(action)
    this.onAction?.(action)
  }

  /** Returns a copy of the recent action log (oldest first). */
  getActionLog(): readonly string[] { return this._actionLog }

  /**
   * Appends a short summary of the action to the ring-buffer.
   * @param action - The dispatched game action
   */
  private _recordAction(action: GameAction): void {
    let entry = action.type
    if ('tileX' in action && 'tileY' in action)
      entry += ` (${(action as any).tileX},${(action as any).tileY})`
    else if ('villagerId' in action)
      entry += ` v=…${(action as any).villagerId.slice(-4)}`
    else if ('resourceId' in action)
      entry += ` r=…${(action as any).resourceId.slice(-4)}`
    else if ('cropId' in action)
      entry += ` c=…${(action as any).cropId.slice(-4)}`
    else if ('seedlingId' in action)
      entry += ` s=…${(action as any).seedlingId.slice(-4)}`

    if (this._actionLog.length >= ACTION_LOG_SIZE) this._actionLog.shift()
    this._actionLog.push(entry)
  }
}