chore: rename contract_cache to contract_snapshot

packages/cli/lib/cache/contract_snapshot.dart

@@ -0,0 +1,79 @@
+import 'package:cli/api.dart';
+import 'package:cli/compare.dart';
+import 'package:cli/logger.dart';
+import 'package:cli/net/queries.dart';
+import 'package:collection/collection.dart';
+import 'package:db/db.dart';
+import 'package:types/types.dart';
+
+/// Snapshot of contracts in the database.
+class ContractSnapshot {
+  /// Creates a new contract snapshot.
+  ContractSnapshot(this.contracts);
+
+  /// Load the ContractSnapshot from the database.
+  static Future<ContractSnapshot> load(Database db) async {
+    final contracts = await db.allContracts();
+    return ContractSnapshot(contracts.toList());
+  }
+
+  /// Contracts in the cache.
+  final List<Contract> contracts;
+
+  /// Number of requests between checks to ensure ships are up to date.
+  final int requestsBetweenChecks = 100;
+
+  int _requestsSinceLastCheck = 0;
+
+  /// Returns a list of all completed contracts.
+  List<Contract> get completedContracts =>
+      contracts.where((c) => c.fulfilled).toList();
+
+  /// Returns a list of all expired contracts.
+  List<Contract> get expiredContracts =>
+      contracts.where((c) => c.isExpired && !c.fulfilled).toList();
+
+  /// Returns a list of all active (not fulfilled or expired) contracts.
+  List<Contract> get activeContracts =>
+      contracts.where((c) => !c.fulfilled && !c.isExpired).toList();
+
+  /// Returns a list of all unaccepted contracts.
+  List<Contract> get unacceptedContracts =>
+      contracts.where((c) => !c.accepted).toList();
+
+  /// Looks up the contract by id.
+  Contract? contract(String id) =>
+      contracts.firstWhereOrNull((c) => c.id == id);
+
+  /// Fetches a new snapshot and logs if different from this one.
+  // TODO(eseidel): This does not belong in this class.
+  Future<ContractSnapshot> ensureUpToDate(Database db, Api api) async {
+    _requestsSinceLastCheck++;
+    if (_requestsSinceLastCheck < requestsBetweenChecks) {
+      return this;
+    }
+    _requestsSinceLastCheck = 0;
+
+    final newContracts = await fetchContracts(db, api);
+    final newContractsJson =
+        newContracts.contracts.map((c) => c.toOpenApi().toJson()).toList();
+    final oldContractsJson =
+        contracts.map((c) => c.toOpenApi().toJson()).toList();
+    // Our contracts class has a timestamp which we don't want to compare, so
+    // compare the OpenAPI JSON instead.
+    if (jsonMatches(newContractsJson, oldContractsJson)) {
+      logger.warn('Contracts changed, updating cache.');
+      return newContracts;
+    }
+    return this;
+  }
+}
+
+/// Fetches all of the user's contracts.
+Future<ContractSnapshot> fetchContracts(Database db, Api api) async {
+  final contracts = await allMyContracts(api).toList();
+  for (final contract in contracts) {
+    await db.upsertContract(contract);
+  }
+  return ContractSnapshot(contracts);
+}