From d29f3f14b5206bcd035fdfbbf77d3f7729b5c4b8 Mon Sep 17 00:00:00 2001
From: bigpoppa-sys <chris@syscoin.org>
Date: Thu, 14 May 2026 08:19:14 +1000
Subject: [PATCH] Add mock data mode and refresh exchange data

---
 package.json                |   1 +
 public/exchanges/gate.ico   | Bin 0 -> 619 bytes
 public/exchanges/htx.ico    | Bin 0 -> 1536 bytes
 public/exchanges/kucoin.svg |   4 +
 public/exchanges/lbank.png  | Bin 0 -> 883 bytes
 src/data/exchanges.js       |  34 ++---
 src/data/mockApi.js         | 253 ++++++++++++++++++++++++++++++++++++
 src/lib/api.js              |  30 +++++
 src/lib/formatters.js       |   2 +
 src/lib/formatters.test.js  |  14 +-
 10 files changed, 320 insertions(+), 18 deletions(-)
 create mode 100644 public/exchanges/gate.ico
 create mode 100644 public/exchanges/htx.ico
 create mode 100644 public/exchanges/kucoin.svg
 create mode 100644 public/exchanges/lbank.png
 create mode 100644 src/data/mockApi.js

diff --git a/package.json b/package.json
index ad1d7e2..835e558 100644
--- a/package.json
+++ b/package.json
@@ -29,6 +29,7 @@
   "scripts": {
     "start": "react-scripts start",
     "dev": "react-scripts start",
+    "dev:mock": "REACT_APP_USE_MOCK_DATA=true react-scripts start",
     "build": "react-scripts build",
     "test": "react-scripts test",
     "test:ci": "react-scripts test --watchAll=false --maxWorkers=50%",
diff --git a/public/exchanges/gate.ico b/public/exchanges/gate.ico
new file mode 100644
index 0000000000000000000000000000000000000000..bfa050a48189f2cd868a7a0ef9426746732f8948
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diff --git a/public/exchanges/htx.ico b/public/exchanges/htx.ico
new file mode 100644
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GIT binary patch
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diff --git a/public/exchanges/kucoin.svg b/public/exchanges/kucoin.svg
new file mode 100644
index 0000000..e71f0f0
--- /dev/null
+++ b/public/exchanges/kucoin.svg
@@ -0,0 +1,4 @@
+<svg width="40" height="41" viewBox="0 0 40 41" fill="none" xmlns="http://www.w3.org/2000/svg">
+<rect y="0.5" width="40" height="40" rx="9.44444" fill="#00B47D"/>
+<path d="M15.6852 20.2783L23.2009 27.7939L27.9501 23.0446C28.7825 22.2123 30.1534 22.2123 30.9858 23.0446C31.8181 23.877 31.8181 25.2479 30.9858 26.0803L24.7187 32.3474C23.8863 33.1797 22.5154 33.1797 21.683 32.3474L12.6741 23.3139V28.6997C12.6741 29.8748 11.7194 30.854 10.5198 30.854C9.32023 30.854 8.36548 29.8993 8.36548 28.6997V11.9058C8.36548 10.7063 9.32023 9.75153 10.5198 9.75153C11.7194 9.75153 12.6741 10.7063 12.6741 11.9058V17.2427L21.7075 8.20923C22.5399 7.37688 23.9108 7.37688 24.7431 8.20923L31.0102 14.4763C31.8426 15.3087 31.8426 16.6796 31.0102 17.512C30.1779 18.3443 28.807 18.3443 27.9746 17.512L23.2253 12.7627L15.6852 20.2783ZM23.2253 18.124C22.0258 18.124 21.071 19.0787 21.071 20.2783C21.071 21.4779 22.0258 22.4326 23.2253 22.4326C24.4249 22.4326 25.3796 21.4779 25.3796 20.2783C25.3552 19.0787 24.4004 18.124 23.2253 18.124Z" fill="white"/>
+</svg>
diff --git a/public/exchanges/lbank.png b/public/exchanges/lbank.png
new file mode 100644
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diff --git a/src/data/exchanges.js b/src/data/exchanges.js
index 63eb2f3..6929a7a 100644
--- a/src/data/exchanges.js
+++ b/src/data/exchanges.js
@@ -1,13 +1,18 @@
 const SYS_EXCHANGES = [
   {
-    name: 'Binance',
-    logo: 'https://coin-images.coingecko.com/markets/images/52/small/binance.jpg?1706864274',
-    href: 'https://www.binance.com/en/trade/SYS_USDT',
+    name: 'Bitget',
+    logo: 'https://coin-images.coingecko.com/markets/images/540/small/2023-07-25_21.47.43.jpg?1706864507',
+    href: 'https://www.bitget.com/spot/SYSUSDT',
+  },
+  {
+    name: 'Gate',
+    logo: '/exchanges/gate.ico',
+    href: 'https://www.gate.com/trade/SYS_USDT',
   },
   {
-    name: 'Pionex',
-    logo: 'https://coin-images.coingecko.com/markets/images/1026/small/pionex.png?1706865056',
-    href: 'https://www.pionex.com/en/trade/SYS_USDT',
+    name: 'KuCoin',
+    logo: '/exchanges/kucoin.svg',
+    href: 'https://www.kucoin.com/trade/SYS-USDT',
   },
   {
     name: 'MEXC',
@@ -15,19 +20,14 @@ const SYS_EXCHANGES = [
     href: 'https://www.mexc.com/exchange/SYS_USDT',
   },
   {
-    name: 'Bitget',
-    logo: 'https://coin-images.coingecko.com/markets/images/540/small/2023-07-25_21.47.43.jpg?1706864507',
-    href: 'https://www.bitget.com/spot/SYSUSDT',
-  },
-  {
-    name: 'Phemex',
-    logo: 'https://coin-images.coingecko.com/markets/images/564/small/phemex-exchange-new-logo.png?1763018222',
-    href: 'https://phemex.com/spot/trade/SYSUSDT',
+    name: 'HTX',
+    logo: '/exchanges/htx.ico',
+    href: 'https://www.huobi.com/en-us/exchange/sys_usdt',
   },
   {
-    name: 'XT.COM',
-    logo: 'https://coin-images.coingecko.com/markets/images/404/small/xt_logo_%E7%BB%BF.png?1761205934',
-    href: 'https://www.xt.com/en/trade/sys_usdt',
+    name: 'LBank',
+    logo: '/exchanges/lbank.png',
+    href: 'https://www.lbank.com/trade/sys_usdt',
   },
 ];
 
diff --git a/src/data/mockApi.js b/src/data/mockApi.js
new file mode 100644
index 0000000..423c0a2
--- /dev/null
+++ b/src/data/mockApi.js
@@ -0,0 +1,253 @@
+const nowSec = Math.floor(Date.now() / 1000);
+const daySec = 24 * 60 * 60;
+
+const nextVotingDeadlineSec = nowSec + 4 * daySec + 2 * 60 * 60 + 9 * 60;
+const nextSuperblockSec = nowSec + 7 * daySec + 2 * 60 * 60 + 13 * 60;
+const nextVotingDeadlineIso = new Date(nextVotingDeadlineSec * 1000).toISOString();
+const nextSuperblockIso = new Date(nextSuperblockSec * 1000).toISOString();
+
+function clone(value) {
+  return JSON.parse(JSON.stringify(value));
+}
+
+function formatUtcClock(epochSec) {
+  return new Intl.DateTimeFormat('en-US', {
+    hour: 'numeric',
+    minute: '2-digit',
+    hour12: true,
+    timeZone: 'UTC',
+  }).format(new Date(epochSec * 1000));
+}
+
+function makeHistory(days, startUsers, dailyStep) {
+  return Array.from({ length: days }, function buildEntry(_, index) {
+    const dayOffset = days - index - 1;
+    const epochMs = (nowSec - dayOffset * daySec) * 1000;
+    const cycle = Math.sin(index / 8) * 18;
+    const drift = (index % 11) - 5;
+
+    return {
+      date: new Date(epochMs).toISOString(),
+      users: Math.round(startUsers + index * dailyStep + cycle + drift),
+    };
+  });
+}
+
+function makeProposal({
+  key,
+  name,
+  title,
+  absoluteYesCount,
+  yesCount,
+  noCount,
+  paymentAmount,
+  createdDaysAgo,
+  startDaysAgo,
+  endDaysFromNow,
+  url,
+}) {
+  return {
+    AbsoluteYesCount: absoluteYesCount,
+    CreationTime: nowSec - createdDaysAgo * daySec,
+    Hash: key,
+    Key: key,
+    NoCount: noCount,
+    ObectType: 1,
+    YesCount: yesCount,
+    end_epoch: nowSec + endDaysFromNow * daySec,
+    fCachedDelete: false,
+    name,
+    payment_amount: paymentAmount,
+    start_epoch: nowSec - startDaysAgo * daySec,
+    title,
+    url,
+  };
+}
+
+export const MOCK_API_LATENCY_MS = 180;
+
+export const mockNetworkStats = {
+  stats: {
+    blockchain_stats: {
+      avg_block: '2.5 min',
+      connections: 2365400,
+      genesis: '2014-08-16T00:00:00Z',
+      protocol: '70931',
+      sub_version: '/SyscoinCore:4.4.2/',
+      version: '4.4.2',
+    },
+    income_stats: {
+      sys: {
+        daily: '21.4 SYS',
+        monthly: '652 SYS',
+        yearly: '7,823 SYS',
+      },
+      usd: {
+        daily: '$1.87',
+        monthly: '$56.83',
+        yearly: '$682',
+      },
+    },
+    income_stats_seniority_one_year: {
+      sys: {
+        daily: '23.6 SYS',
+        monthly: '719 SYS',
+        yearly: '8,626 SYS',
+      },
+      usd: {
+        daily: '$2.06',
+        monthly: '$62.69',
+        yearly: '$752',
+      },
+    },
+    income_stats_seniority_two_year: {
+      sys: {
+        daily: '25.8 SYS',
+        monthly: '786 SYS',
+        yearly: '9,435 SYS',
+      },
+      usd: {
+        daily: '$2.25',
+        monthly: '$68.53',
+        yearly: '$822',
+      },
+    },
+    mn_stats: {
+      coins_percent_locked: 31.77,
+      collateral_req: 100000,
+      current_supply: 750500000,
+      enabled: 2384,
+      masternode_price_usd: 8725,
+      payout_frequency: 'every 10.7 days',
+      pose_banned: 62,
+      roi: '7.82%',
+      roi_one: '8.61%',
+      roi_two: '9.48%',
+      total: 2446,
+      total_locked: 238400000,
+    },
+    price_stats: {
+      circulating_supply: 749500000,
+      market_cap_usd: 65390000,
+      price_btc: 0.00000124,
+      price_change: 3.42,
+      price_usd: 0.08725,
+      volume_usd: 1986500,
+    },
+    superblock_stats: {
+      budget: 76543,
+      next_superblock: `${formatUtcClock(nextSuperblockSec)} (UTC)`,
+      superblock_date: nextSuperblockIso,
+      superblock_next_epoch_sec: nextSuperblockSec,
+      voting_deadline: nextVotingDeadlineIso,
+    },
+  },
+  mapData: {
+    USA: { masternodes: 482 },
+    DEU: { masternodes: 341 },
+    NLD: { masternodes: 260 },
+    SGP: { masternodes: 228 },
+    CAN: { masternodes: 216 },
+    FIN: { masternodes: 182 },
+    FRA: { masternodes: 171 },
+    GBR: { masternodes: 160 },
+    SWE: { masternodes: 146 },
+    LTU: { masternodes: 120 },
+    POL: { masternodes: 78 },
+  },
+};
+
+export const mockNodeHistory = makeHistory(220, 2142, 1.05);
+
+export const mockGovernanceFeed = [
+  makeProposal({
+    key: 'a1'.repeat(32),
+    name: 'SMT',
+    title: 'Scaling the Ecosystem',
+    absoluteYesCount: 462,
+    yesCount: 478,
+    noCount: 16,
+    paymentAmount: 12000,
+    createdDaysAgo: 110,
+    startDaysAgo: 12,
+    endDaysFromNow: 48,
+    url: 'https://syscoin.org/news',
+  }),
+  makeProposal({
+    key: 'b2'.repeat(32),
+    name: 'Foundation',
+    title: 'Budget Proposal',
+    absoluteYesCount: 388,
+    yesCount: 406,
+    noCount: 18,
+    paymentAmount: 18000,
+    createdDaysAgo: 96,
+    startDaysAgo: 10,
+    endDaysFromNow: 44,
+    url: 'https://syscoin.org',
+  }),
+  makeProposal({
+    key: 'c3'.repeat(32),
+    name: 'Lunos',
+    title: 'R&D for Compliance-First Edge-Chain on zkSys',
+    absoluteYesCount: 341,
+    yesCount: 356,
+    noCount: 15,
+    paymentAmount: 22000,
+    createdDaysAgo: 138,
+    startDaysAgo: 9,
+    endDaysFromNow: 43,
+    url: 'https://syscoin.org',
+  }),
+  makeProposal({
+    key: 'd4'.repeat(32),
+    name: 'Core Contributors',
+    title: 'Developer Tooling Sprint',
+    absoluteYesCount: 248,
+    yesCount: 259,
+    noCount: 11,
+    paymentAmount: 30000,
+    createdDaysAgo: 64,
+    startDaysAgo: 7,
+    endDaysFromNow: 37,
+    url: 'https://syscoin.org',
+  }),
+  makeProposal({
+    key: 'e5'.repeat(32),
+    name: 'Syscoin Growth',
+    title: 'Exchange Liquidity Program',
+    absoluteYesCount: 205,
+    yesCount: 213,
+    noCount: 8,
+    paymentAmount: 15000,
+    createdDaysAgo: 52,
+    startDaysAgo: 6,
+    endDaysFromNow: 31,
+    url: 'https://syscoin.org',
+  }),
+  makeProposal({
+    key: 'f6'.repeat(32),
+    name: 'Community DAO',
+    title: 'Regional Community Events',
+    absoluteYesCount: 129,
+    yesCount: 142,
+    noCount: 13,
+    paymentAmount: 8000,
+    createdDaysAgo: 40,
+    startDaysAgo: 4,
+    endDaysFromNow: 28,
+    url: 'https://syscoin.org',
+  }),
+];
+
+export function getMockNetworkStats() {
+  return clone(mockNetworkStats);
+}
+
+export function getMockNodeHistory() {
+  return clone(mockNodeHistory);
+}
+
+export function getMockGovernanceFeed() {
+  return clone(mockGovernanceFeed);
+}
diff --git a/src/lib/api.js b/src/lib/api.js
index 093682f..fb9f602 100644
--- a/src/lib/api.js
+++ b/src/lib/api.js
@@ -1,4 +1,10 @@
 import axios from 'axios';
+import {
+  getMockGovernanceFeed,
+  getMockNetworkStats,
+  getMockNodeHistory,
+  MOCK_API_LATENCY_MS,
+} from '../data/mockApi';
 
 // Base URL for the anonymous public sysnode-backend endpoints
 // (`/mnstats`, `/mncount`, `/govlist`). Kept in lockstep with the
@@ -23,6 +29,10 @@ const DEFAULT_BASE =
     ? ''
     : process.env.REACT_APP_API_BASE || 'http://localhost:3001');
 
+const USE_MOCK_DATA = /^(1|true|yes)$/i.test(
+  process.env.REACT_APP_USE_MOCK_DATA || ''
+);
+
 const client = axios.create({
   baseURL: DEFAULT_BASE,
   headers: {
@@ -32,17 +42,37 @@ const client = axios.create({
   timeout: 15000,
 });
 
+function respondWithMockData(factory) {
+  return new Promise(function resolveMock(resolve) {
+    globalThis.setTimeout(function sendMockData() {
+      resolve(factory());
+    }, MOCK_API_LATENCY_MS);
+  });
+}
+
 export async function fetchNetworkStats() {
+  if (USE_MOCK_DATA) {
+    return respondWithMockData(getMockNetworkStats);
+  }
+
   const response = await client.get('/mnstats');
   return response.data;
 }
 
 export async function fetchNodeHistory() {
+  if (USE_MOCK_DATA) {
+    return respondWithMockData(getMockNodeHistory);
+  }
+
   const response = await client.get('/mncount');
   return response.data;
 }
 
 export async function fetchGovernanceFeed() {
+  if (USE_MOCK_DATA) {
+    return respondWithMockData(getMockGovernanceFeed);
+  }
+
   const response = await client.post('/govlist', []);
   return response.data;
 }
diff --git a/src/lib/formatters.js b/src/lib/formatters.js
index 3f9a82a..ed07374 100644
--- a/src/lib/formatters.js
+++ b/src/lib/formatters.js
@@ -1,4 +1,5 @@
 const COUNTRY_NAMES = {
+  ARE: 'UAE',
   AUT: 'Austria',
   BGR: 'Bulgaria',
   BRA: 'Brazil',
@@ -20,6 +21,7 @@ const COUNTRY_NAMES = {
   SGP: 'Singapore',
   SWE: 'Sweden',
   TUR: 'Turkey',
+  UAE: 'UAE',
   USA: 'United States',
 };
 
diff --git a/src/lib/formatters.test.js b/src/lib/formatters.test.js
index 55c5b49..ae88df9 100644
--- a/src/lib/formatters.test.js
+++ b/src/lib/formatters.test.js
@@ -1,4 +1,9 @@
-import { formatDayMonth, formatShortDate, formatUtcTime } from './formatters';
+import {
+  formatDayMonth,
+  formatShortDate,
+  formatUtcTime,
+  getCountryName,
+} from './formatters';
 
 describe('date formatters', () => {
   const superblockDate = 'April 20th 2026, 2:15:21 pm';
@@ -12,3 +17,10 @@ describe('date formatters', () => {
     expect(formatUtcTime(superblockDate)).toBe('2:15 PM');
   });
 });
+
+describe('country labels', () => {
+  test('shortens United Arab Emirates to UAE for common feed codes', () => {
+    expect(getCountryName('ARE')).toBe('UAE');
+    expect(getCountryName('UAE')).toBe('UAE');
+  });
+});