import { createHash } from 'node:crypto';

export type ProducerHost = 'claude' | 'codex' | 'gemini';
export type ProducerVersion = 'v2' | 'v3';
export type ProducerMode = 'daily' | 'comprehensive';
export type ProducerStack = 'node' | 'bun' | 'python' | 'rails';
export type ProducerVariant = 'vulnerable' | 'fixed';

export interface ProducerCell {
  id: string;
  caseId: string;
  stack: ProducerStack;
  variant: ProducerVariant;
  version: ProducerVersion;
  mode: ProducerMode;
  repetition: 1 | 2 | 3;
  model: string;
  host: ProducerHost;
  budgetSeconds: number;
  sourceHash: string;
  skillHash: string;
}

export interface ProducerSourceEntry {
  path: string;
  sha256: string;
  bytes: number;
}

/**
 * This control file is consumed before a producing agent starts. It must never
 * be placed inside the application repository or retained on the producer.
 */
export interface ProducerInput {
  schemaVersion: 1;
  cell: ProducerCell;
  /** Exact canonical portable payload: root SKILL.md plus its manifest-listed sections. */
  skill: string;
  source: ProducerSourceEntry[];
}

export interface ProducerArtifactIdentity {
  sha256: string;
  bytes: number;
}

export interface ProducerInstallationIdentity {
  schemaVersion: 1;
  producer: ProducerArtifactIdentity;
  launcher: ProducerArtifactIdentity;
  core: ProducerArtifactIdentity;
  watchdog: ProducerArtifactIdentity;
  /** The adjacent manifest is exactly `<coreSha256>\n`; bind both its bytes and declaration. */
  generation: {
    coreSha256: string;
    manifest: ProducerArtifactIdentity;
  };
  embeddedCatalogs: {
    runtimeRevision: string;
    runtimeBuildRevision: string;
    runtimeSha256: string;
    scannerRevision: string;
    scannerSha256: string;
  };
  identityHash: string;
}

export interface ProducerProviderIdentity {
  schemaVersion: 1;
  family: 'claude' | 'gpt' | 'gemini';
  policyRevision: string;
  executable: ProducerArtifactIdentity;
  argsPrefix: string[];
  version: string;
  identityHash: string;
}

export interface ProducerArtifactInventory {
  schemaVersion: 1;
  root: 'security/cso';
  /** Sorted safe paths relative to root within the retained helper home. */
  entries: ProducerSourceEntry[];
  totalBytes: number;
  identityHash: string;
}

export interface ProducerReceipt {
  schemaVersion: 1;
  cell: ProducerCell;
  inputHash: string;
  installationIdentity: ProducerInstallationIdentity;
  providerIdentity: ProducerProviderIdentity;
  artifacts: ProducerArtifactInventory;
  startedAt: string;
  finishedAt: string;
  status: 'succeeded' | 'failed';
  requestedModel: string;
  modelUsed: string;
  /** Provider-reported when it differs; otherwise the exact CLI model pin. */
  modelIdentitySource: 'provider_reported' | 'requested_pin';
  durationMs: number;
  firstUsefulResultMs: null;
  toolCalls: number;
  output: string;
  outputHash: string;
  usage: {
    /** CLI/provider-reported tokens. Null means the adapter did not report usage. */
    inputTokens: number | null;
    outputTokens: number | null;
    cachedTokens: number | null;
    /** Pricing-table estimate, not a host-billed amount. */
    estimatedCostUSD: number | null;
  };
  error?: { code: string; reason: string };
  receiptHash: string;
}

/** Compact trusted index; raw output remains in the separately retained receipt. */
export type ProducerReceiptIndex = Omit<ProducerReceipt, 'output' | 'error'> & {
  error?: { code: string };
};

export const sha256 = (value: string | Buffer): string => createHash('sha256').update(value).digest('hex');

export function producerInputHash(input: ProducerInput): string {
  return sha256(JSON.stringify(input));
}

export function producerReceiptHash(receipt: Omit<ProducerReceipt, 'receiptHash'>): string {
  return sha256(JSON.stringify(receipt));
}

export function producerInstallationIdentityHash(identity: Omit<ProducerInstallationIdentity, 'identityHash'>): string {
  if (!identity.generation || !identity.generation.manifest || identity.generation.coreSha256 !== identity.core.sha256 ||
      identity.generation.manifest.bytes !== 65 ||
      identity.generation.manifest.sha256 !== sha256(`${identity.generation.coreSha256}\n`)) {
    throw new Error('INVALID_PRODUCER_GENERATION_IDENTITY');
  }
  return sha256(JSON.stringify(identity));
}

export function producerProviderIdentityHash(identity: Omit<ProducerProviderIdentity, 'identityHash'>): string {
  return sha256(JSON.stringify(identity));
}

export function producerArtifactInventoryHash(inventory: Omit<ProducerArtifactInventory, 'identityHash'>): string {
  return sha256(JSON.stringify(inventory));
}