export const EXTENSION_ID = "pi-midrun-compact";
export const COMMAND_NAME = "midrun-compact";

export const DEFAULT_COMPACTION_INSTRUCTIONS =
  "Preserve the active user task, completed work, decisions, changed files, failures, pending tool-loop state, and exact next steps so execution can resume immediately after compaction.";

export interface MidrunCompactConfig {
  enabled: boolean;
  thresholdPercent: number;
  autoResume: boolean;
  notify: boolean;
  customCompactionInstructions: string;
}

export const DEFAULT_CONFIG: Readonly<MidrunCompactConfig> = Object.freeze({
  enabled: true,
  thresholdPercent: 75,
  autoResume: true,
  notify: true,
  customCompactionInstructions: DEFAULT_COMPACTION_INSTRUCTIONS,
});

export interface LoadedConfig {
  config: MidrunCompactConfig;
  valid: boolean;
  automaticEnabled: boolean;
  globalPath: string;
  projectPath?: string;
  loadedSources: string[];
  errors: string[];
  warnings: string[];
  projectConfigSkippedAsUntrusted: boolean;
}

export type RuntimePhase = "idle" | "compacting" | "resume-pending" | "failed";
export type CompactionSource = "threshold" | "now" | "retry";

export interface TriggerSnapshot {
  tokens: number;
  contextWindow: number;
  percent: number;
  thresholdPercent: number;
}

export interface RuntimeState {
  phase: RuntimePhase;
  generation: number;
  triggerSessionId?: string;
  triggerTokens?: number;
  triggerPercent?: number;
  triggerContextWindow?: number;
  triggerSource?: CompactionSource;
  lastFailureKey?: string;
  lastBlockedFailureKey?: string;
  lastError?: string;
}

export interface UsableContextUsage {
  tokens: number;
  contextWindow: number;
  percent: number;
}

export interface ThresholdEvaluation {
  usage: UsableContextUsage;
  trigger: TriggerSnapshot;
}