import type { IActionConfig, IActionContext, TPowerStatus } from './actions/base-action.ts';
import type { IUpsStatus } from './ups-status.ts';

export interface IUpsActionSource {
  id: string;
  name: string;
  actions?: IActionConfig[];
}

export type TUpsTriggerReason = IActionContext['triggerReason'];

export type TActionExecutionDecision =
  | { type: 'suppressed'; message: string }
  | { type: 'legacyShutdown'; reason: string }
  | { type: 'skip' }
  | { type: 'execute'; actions: IActionConfig[]; context: IActionContext };

export function buildUpsActionContext(
  ups: IUpsActionSource,
  status: IUpsStatus,
  previousStatus: IUpsStatus | undefined,
  triggerReason: TUpsTriggerReason,
  timestamp: number = Date.now(),
): IActionContext {
  return {
    upsId: ups.id,
    upsName: ups.name,
    powerStatus: status.powerStatus as TPowerStatus,
    batteryCapacity: status.batteryCapacity,
    batteryRuntime: status.batteryRuntime,
    previousPowerStatus: (previousStatus?.powerStatus || 'unknown') as TPowerStatus,
    timestamp,
    triggerReason,
  };
}

export function applyDefaultShutdownDelay(
  actions: IActionConfig[],
  defaultDelayMinutes: number,
): IActionConfig[] {
  return actions.map((action) => {
    if (action.type !== 'shutdown' || action.shutdownDelay !== undefined) {
      return action;
    }

    return {
      ...action,
      shutdownDelay: defaultDelayMinutes,
    };
  });
}

export function decideUpsActionExecution(
  isPaused: boolean,
  ups: IUpsActionSource,
  status: IUpsStatus,
  previousStatus: IUpsStatus | undefined,
  triggerReason: TUpsTriggerReason,
  timestamp: number = Date.now(),
): TActionExecutionDecision {
  if (isPaused) {
    return {
      type: 'suppressed',
      message: `[PAUSED] Actions suppressed for UPS ${ups.name} (trigger: ${triggerReason})`,
    };
  }

  const actions = ups.actions || [];

  if (actions.length === 0 && triggerReason === 'thresholdViolation') {
    return {
      type: 'legacyShutdown',
      reason: `UPS "${ups.name}" battery or runtime below threshold`,
    };
  }

  if (actions.length === 0) {
    return { type: 'skip' };
  }

  return {
    type: 'execute',
    actions,
    context: buildUpsActionContext(ups, status, previousStatus, triggerReason, timestamp),
  };
}