1 files changed, 56 insertions, 0 deletions
diff --git a/packages/website/ts/local_storage/tracked_token_storage.ts b/packages/website/ts/local_storage/tracked_token_storage.ts
new file mode 100644
index 000000000..0b54a66e0
--- /dev/null
+++ b/packages/website/ts/local_storage/tracked_token_storage.ts
@@ -0,0 +1,56 @@
+import * as _ from 'lodash';
+import {Token, TrackedTokensByNetworkId} from 'ts/types';
+import {localStorage} from 'ts/local_storage/local_storage';
+
+const TRACKED_TOKENS_KEY = 'trackedTokens';
+
+export const trackedTokenStorage = {
+    addTrackedTokenToUser(userAddress: string, networkId: number, token: Token) {
+        const trackedTokensByUserAddress = this.getTrackedTokensByUserAddress();
+        let trackedTokensByNetworkId = trackedTokensByUserAddress[userAddress];
+        if (_.isUndefined(trackedTokensByNetworkId)) {
+            trackedTokensByNetworkId = {};
+        }
+        const trackedTokens = !_.isUndefined(trackedTokensByNetworkId[networkId]) ?
+                                    trackedTokensByNetworkId[networkId] :
+                                    [];
+        trackedTokens.push(token);
+        trackedTokensByNetworkId[networkId] = trackedTokens;
+        trackedTokensByUserAddress[userAddress] = trackedTokensByNetworkId;
+        const trackedTokensByUserAddressJSONString = JSON.stringify(trackedTokensByUserAddress);
+        localStorage.setItem(TRACKED_TOKENS_KEY, trackedTokensByUserAddressJSONString);
+    },
+    getTrackedTokensByUserAddress(): TrackedTokensByNetworkId {
+        const trackedTokensJSONString = localStorage.getItemIfExists(TRACKED_TOKENS_KEY);
+        if (_.isEmpty(trackedTokensJSONString)) {
+            return {};
+        }
+        const trackedTokensByUserAddress = JSON.parse(trackedTokensJSONString);
+        return trackedTokensByUserAddress;
+    },
+    getTrackedTokensIfExists(userAddress: string, networkId: number): Token[] {
+        const trackedTokensJSONString = localStorage.getItemIfExists(TRACKED_TOKENS_KEY);
+        if (_.isEmpty(trackedTokensJSONString)) {
+            return undefined;
+        }
+        const trackedTokensByUserAddress = JSON.parse(trackedTokensJSONString);
+        const trackedTokensByNetworkId = trackedTokensByUserAddress[userAddress];
+        if (_.isUndefined(trackedTokensByNetworkId)) {
+            return undefined;
+        }
+        const trackedTokens = trackedTokensByNetworkId[networkId];
+        return trackedTokens;
+    },
+    removeTrackedToken(userAddress: string, networkId: number, tokenAddress: string) {
+        const trackedTokensByUserAddress = this.getTrackedTokensByUserAddress();
+        const trackedTokensByNetworkId = trackedTokensByUserAddress[userAddress];
+        const trackedTokens = trackedTokensByNetworkId[networkId];
+        const remainingTrackedTokens = _.filter(trackedTokens, (token: Token) => {
+            return token.address !== tokenAddress;
+        });
+        trackedTokensByNetworkId[networkId] = remainingTrackedTokens;
+        trackedTokensByUserAddress[userAddress] = trackedTokensByNetworkId;
+        const trackedTokensByUserAddressJSONString = JSON.stringify(trackedTokensByUserAddress);
+        localStorage.setItem(TRACKED_TOKENS_KEY, trackedTokensByUserAddressJSONString);
+    },
+};