[PM-24467] Introduce cipher risk service

libs/common/src/vault/abstractions/cipher-risk.service.ts

@@ -0,0 +1,55 @@
+import type {
+  CipherRiskResult,
+  CipherRiskOptions,
+  ExposedPasswordResult,
+  PasswordReuseMap,
+  CipherId,
+} from "@bitwarden/sdk-internal";
+
+import { UserId } from "../../types/guid";
+import { CipherView } from "../models/view/cipher.view";
+
+export abstract class CipherRiskService {
+  /**
+   * Compute password risks for multiple ciphers.
+   * Only processes Login ciphers with passwords.
+   *
+   * @param ciphers - The ciphers to evaluate for password risks
+   * @param userId - The user ID for SDK client context
+   * @param options - Optional configuration for risk computation (passwordMap, checkExposed)
+   * @returns Array of CipherRisk results from SDK containing password_strength, exposed_result, and reuse_count
+   */
+  abstract computeRiskForCiphers(
+    ciphers: CipherView[],
+    userId: UserId,
+    options?: CipherRiskOptions,
+  ): Promise<CipherRiskResult[]>;
+
+  /**
+   * Compute password risk for a single cipher by its ID. Will automatically build a password reuse map
+   * from all the user's ciphers via the CipherService.
+   * @param cipherId
+   * @param userId
+   * @param checkExposed - Whether to check if the password has been exposed in data breaches via HIBP
+   * @returns CipherRisk result from SDK containing password_strength, exposed_result, and reuse_count
+   */
+  abstract computeCipherRiskForUser(
+    cipherId: CipherId,
+    userId: UserId,
+    checkExposed?: boolean,
+  ): Promise<CipherRiskResult>;
+
+  /**
+   * Build a password reuse map for the given ciphers.
+   * Maps each password to the number of times it appears across ciphers.
+   * Only processes Login ciphers with passwords.
+   *
+   * @param ciphers - The ciphers to analyze for password reuse
+   * @param userId - The user ID for SDK client context
+   * @returns A map of password to count of occurrences
+   */
+  abstract buildPasswordReuseMap(ciphers: CipherView[], userId: UserId): Promise<PasswordReuseMap>;
+}
+
+// Re-export SDK types for convenience
+export type { CipherRiskResult, CipherRiskOptions, ExposedPasswordResult, PasswordReuseMap };