From 3f31b3196ae1dd3b5828e0d349bee3f51e36cc08 Mon Sep 17 00:00:00 2001
From: Marc Velmer <marc1987@gmail.com>
Date: Tue, 28 Nov 2023 15:47:03 +0100
Subject: [PATCH] Added `nextElectionId` function

---
 src/api/election.ts               | 33 +++++++++++++++++++++++++++++++
 src/services/election.ts          | 19 ++++++++++++++++++
 test/integration/election.test.ts | 20 +++++++++++++++++++
 3 files changed, 72 insertions(+)

diff --git a/src/api/election.ts b/src/api/election.ts
index 6df99a31..4e24d5f3 100644
--- a/src/api/election.ts
+++ b/src/api/election.ts
@@ -4,6 +4,7 @@ import { API } from './api';
 
 enum ElectionAPIMethods {
   INFO = '/elections',
+  NEXT_ELECTION_ID = '/elections/id',
   PRICE = '/elections/price',
   KEYS = '/elections/{id}/keys',
   CREATE = '/elections',
@@ -138,6 +139,13 @@ export interface IElectionCreateResponse {
   metadataURL: number;
 }
 
+export interface IElectionNextIdResponse {
+  /**
+   * The next election identifier
+   */
+  electionID: string;
+}
+
 export enum CensusTypeEnum {
   CENSUS_UNKNOWN = 'CENSUS_UNKNOWN',
   OFF_CHAIN_TREE = 'OFF_CHAIN_TREE',
@@ -409,6 +417,31 @@ export abstract class ElectionAPI extends API {
       .catch(this.isApiError);
   }
 
+  /**
+   * Returns the next election id.
+   *
+   * @param {string} url API endpoint URL
+   * @param {string} organizationId The identifier of the organization
+   * @param {number} censusOrigin The census origin
+   * @param {IVoteMode} envelopeType The envelope type
+   * @returns {Promise<IElectionNextIdResponse>}
+   */
+  public static nextElectionId(
+    url: string,
+    organizationId: string,
+    censusOrigin: number,
+    envelopeType?: Partial<IVoteMode>
+  ): Promise<IElectionNextIdResponse> {
+    return axios
+      .post<IElectionNextIdResponse>(url + ElectionAPIMethods.NEXT_ELECTION_ID, {
+        organizationId,
+        censusOrigin,
+        envelopeType,
+      })
+      .then((response) => response.data)
+      .catch(this.isApiError);
+  }
+
   /**
    * Returns the number of votes of a given election
    *
diff --git a/src/services/election.ts b/src/services/election.ts
index 8bce71f0..89fa12c5 100644
--- a/src/services/election.ts
+++ b/src/services/election.ts
@@ -198,6 +198,25 @@ export class ElectionService extends Service implements ElectionServicePropertie
     return ElectionAPI.create(this.url, payload, metadata);
   }
 
+  /**
+   * Returns the next election id.
+   *
+   * @param {string} address The address of the account
+   * @param {UnpublishedElection} election The unpublished election
+   * @returns {Promise<string>} The next election identifier
+   */
+  nextElectionId(address: string, election: UnpublishedElection): Promise<string> {
+    invariant(this.url, 'No URL set');
+    const censusOrigin = ElectionCore.censusOriginFromCensusType(election.census.type);
+    return ElectionAPI.nextElectionId(this.url, address, censusOrigin, {
+      serial: false, // TODO
+      anonymous: election.electionType.anonymous,
+      encryptedVotes: election.electionType.secretUntilTheEnd,
+      uniqueValues: election.voteType.uniqueChoices,
+      costFromWeight: election.voteType.costFromWeight,
+    }).then((response) => response.electionID);
+  }
+
   /**
    * Fetches the encryption keys from the specified process.
    *
diff --git a/test/integration/election.test.ts b/test/integration/election.test.ts
index e39c0dff..76b20ea9 100644
--- a/test/integration/election.test.ts
+++ b/test/integration/election.test.ts
@@ -916,4 +916,24 @@ describe('Election integration tests', () => {
         expect(election.census.censusURI).toEqual(census2.censusURI);
       });
   }, 185000);
+  it('should return the next election id', async () => {
+    const census = new PlainCensus();
+    census.add(await Wallet.createRandom().getAddress());
+
+    const election = createElection(census);
+
+    await client.createAccount();
+
+    await client
+      .createElection(election)
+      .then((electionId) => {
+        expect(electionId).toMatch(/^[0-9a-fA-F]{64}$/);
+        client.setElectionId(electionId);
+        return waitForElectionReady(client, electionId);
+      })
+      .then(async () => {
+        const nextElectionId = await client.electionService.nextElectionId(await client.wallet.getAddress(), election);
+        expect(nextElectionId).toEqual(client.electionId.slice(0, -1) + '1');
+      });
+  }, 85000);
 });