2 files changed, 90 insertions, 0 deletions
diff --git a/packages/instant/src/constants.ts b/packages/instant/src/constants.ts
index 424f35ecb..a21de2a0f 100644
--- a/packages/instant/src/constants.ts
+++ b/packages/instant/src/constants.ts
@@ -7,3 +7,4 @@ export const GWEI_IN_WEI = new BigNumber(1000000000);
 export const DEFAULT_GAS_PRICE = GWEI_IN_WEI.mul(6);
 export const ETH_GAS_STATION_API_BASE_URL = 'https://ethgasstation.info';
 export const COINBASE_API_BASE_URL = 'https://api.coinbase.com/v2';
+export const PROGRESS_TICK_INTERVAL_MS = 100;
diff --git a/packages/instant/src/util/progress.ts b/packages/instant/src/util/progress.ts
new file mode 100644
index 000000000..33b1cc313
--- /dev/null
+++ b/packages/instant/src/util/progress.ts
@@ -0,0 +1,89 @@
+import { Dispatch } from 'redux';
+
+import { PROGRESS_TICK_INTERVAL_MS } from '../constants';
+import { Action, actions } from '../redux/actions';
+
+const curTimeUnix = () => {
+    return new Date().getTime();
+};
+
+enum TickingState {
+    Ticking,
+    Finishing,
+}
+interface TickingNormalState {
+    state: TickingState.Ticking;
+}
+interface TickingFinishingState {
+    state: TickingState.Finishing;
+    increasePercentageEveryTick: number;
+}
+type TickingStatus = TickingNormalState | TickingFinishingState;
+
+const TICKS_PER_SECOND = 1000 / PROGRESS_TICK_INTERVAL_MS;
+export class Progress {
+    private _startTimeUnix: number;
+    private _expectedTimeMs: number;
+    private _intervalId: number;
+    private _percentageDone: number;
+    private _tickingStatus: TickingStatus;
+
+    // TODO: take in dispatch
+    constructor(expectedTimeMs: number) {
+        const curTime = curTimeUnix();
+        this._startTimeUnix = curTime;
+        this._expectedTimeMs = expectedTimeMs;
+        this._percentageDone = 0;
+        this._intervalId = window.setInterval(this._tick.bind(this), PROGRESS_TICK_INTERVAL_MS); // TODO: is bind necessary?
+        this._tickingStatus = { state: TickingState.Ticking };
+        // TODO: clear interval
+    }
+
+    public setFinishing(): void {
+        const percentLeft = 100 - this._percentageDone;
+        console.log('percentLeft', percentLeft);
+        const increasePercentageEveryTick = percentLeft / TICKS_PER_SECOND;
+        console.log('increase Tick', increasePercentageEveryTick);
+        this._tickingStatus = {
+            state: TickingState.Finishing,
+            increasePercentageEveryTick,
+        };
+    }
+
+    private _tick(): void {
+        const percentageDone =
+            this._tickingStatus.state === TickingState.Finishing
+                ? this._tickFinishing(this._tickingStatus)
+                : this._tickNormal();
+
+        // TODO: max 100
+
+        this._percentageDone = percentageDone;
+        console.log('percentageDone', this._percentageDone);
+        // TODO: max 95
+        if (percentageDone >= 100) {
+            this._clearInterval();
+        }
+        return;
+    }
+
+    // TODO: take param and move out
+    private _tickNormal(): number {
+        const elapsedTimeMs = curTimeUnix() - this._startTimeUnix;
+        // TODO: zero and negative check, use mins and maxs everywhere
+        const percentageDone = elapsedTimeMs / this._expectedTimeMs * 100;
+        return percentageDone;
+    }
+
+    private _tickFinishing(finishingState: TickingFinishingState): number {
+        return this._percentageDone + finishingState.increasePercentageEveryTick;
+    }
+
+    private _clearInterval(): void {
+        return window.clearInterval(this._intervalId);
+    }
+
+    // reset function
+
+    // end function
+}