import type { AnalysisProfileCommitment } from "../../domain/analysisProfile.js";
import type { BinaryTarget } from "../../domain/binaryTarget.js";
import { AnalysisCapabilityUnavailableError } from "../../domain/analysisErrorCore.js";
import { NoBinaryOpenError } from "../../domain/configurationErrors.js";
import { ProviderAdapterError } from "../../domain/providerAdapterError.js";
import { type AnalysisError } from "../../domain/analysisErrorBase.js";
import type { JsonValue } from "../../domain/jsonValue.js";
import type { EvidenceSubjectTarget } from "../../domain/evidence.js";
import { err, ok, type Result } from "../../domain/result.js";
import type {
  AnalysisClient,
  AnalysisExecution,
  AnalysisOperation,
  CapabilityDescriptor,
} from "../AnalysisProvider.js";
import { isSnapshotCacheable } from "./AnalysisSnapshotCache.js";
import type { SessionProviderRoute } from "./SessionProviderRouter.js";

interface ActiveExecutionBinding {
  readonly target: BinaryTarget;
  readonly client: AnalysisClient;
  readonly profile: AnalysisProfileCommitment | null;
  readonly route: SessionProviderRoute;
}

export interface PreparedSessionExecution {
  readonly active: ActiveExecutionBinding;
  readonly capability: CapabilityDescriptor | undefined;
  readonly profile: AnalysisProfileCommitment | undefined;
  readonly cacheable: boolean;
  readonly cached: AnalysisExecution | undefined;
}

interface PrepareSessionExecutionInput {
  readonly active: ActiveExecutionBinding | undefined;
  readonly operation: AnalysisOperation;
  readonly parameters: Readonly<Record<string, JsonValue>>;
  readonly unboundOperationError: (
    operation: AnalysisOperation,
    route: SessionProviderRoute,
  ) => AnalysisError | undefined;
  readonly lookupSnapshot: (
    target: BinaryTarget,
    profile: AnalysisProfileCommitment,
    operation: AnalysisOperation,
    parameters: Readonly<Record<string, JsonValue>>,
  ) => AnalysisExecution | undefined;
}

/** Resolve capability, profile, and snapshot state before invoking a provider. */
export const prepareSessionExecution = (
  input: PrepareSessionExecutionInput,
): Result<PreparedSessionExecution, AnalysisError> => {
  const {
    active,
    operation,
    parameters,
    unboundOperationError,
    lookupSnapshot,
  } = input;
  if (active === undefined) return err(new NoBinaryOpenError());
  const capability = active.route.capabilities?.get(operation);
  if (
    active.route.capabilities !== undefined &&
    capability?.available !== true
  ) {
    const selectionError = unboundOperationError(operation, active.route);
    if (selectionError !== undefined) return err(selectionError);
    return err(
      new AnalysisCapabilityUnavailableError(
        active.route.binding?.identity.id ?? active.route.identity.id,
        operation,
        capability?.reason ?? "operation is not declared by this provider",
      ),
    );
  }
  const profile =
    active.profile !== null &&
    (capability === undefined ||
      capability.provider.id === active.profile.provider.id)
      ? active.profile
      : undefined;
  const cacheable =
    profile !== undefined &&
    isSnapshotCacheable(operation, capability, parameters);
  const cached = cacheable
    ? lookupSnapshot(active.target, profile, operation, parameters)
    : undefined;
  return ok({ active, capability, profile, cacheable, cached });
};

/** Attach the selected profile only when the provider identity agrees. */
export const commitExecutionProfile = (
  operation: AnalysisOperation,
  result: Result<AnalysisExecution, AnalysisError>,
  profile: AnalysisProfileCommitment | undefined,
): Result<AnalysisExecution, AnalysisError> => {
  if (!result.ok || profile === undefined) return result;
  const provider = result.value.provider;
  if (
    provider.id !== profile.provider.id ||
    provider.name !== profile.provider.name ||
    provider.version !== profile.provider.version
  )
    return err(
      new ProviderAdapterError(profile.provider.id, `${operation}:profile`),
    );
  return ok({
    ...result.value,
    analysisProfile: structuredClone(profile),
  });
};

/** Bind an execution to the selected target, preserving valid artifact subjects. */
export const bindExecutionTarget = (
  result: Result<AnalysisExecution, AnalysisError>,
  operation: AnalysisOperation,
  target: BinaryTarget,
): Result<AnalysisExecution, AnalysisError> => {
  if (!result.ok) return result;
  const subject: EvidenceSubjectTarget = {
    path: target.path,
    sha256: target.sha256,
    format:
      target.format === "analysis-database"
        ? "analysis-database"
        : target.format,
    ...(target.architecture === undefined
      ? {}
      : { architecture: target.architecture }),
  };
  if (
    result.value.subject !== null &&
    result.value.subject.sha256 !== target.sha256 &&
    !isArtifactBundleSubject(operation, result.value.subject, target)
  )
    return err(
      new ProviderAdapterError(
        result.value.provider.id,
        `${operation}:subject`,
      ),
    );
  return ok({ ...result.value, subject: result.value.subject ?? subject });
};

const isArtifactBundleSubject = (
  operation: AnalysisOperation,
  subject: EvidenceSubjectTarget,
  target: BinaryTarget,
): boolean =>
  (operation === "inventory_artifact" ||
    operation === "inspect_artifact" ||
    operation === "extract_artifact") &&
  subject.path === (target.sourcePath ?? target.path);