feat: add light node upgrade top up methods (#372)

* feat: add top up

* chore: remove console.log

* build: add pseudo-missing dependency

* feat: add missing top up components

* fix: crypto route

* feat(wip): add gift wallet logic

* fix: fix gift wallet flows

* feat: simplify flow without fund step

* feat: add loading screens

* fix: remove alert

* fix: prepend http if needed

* fix: fix bug that was reintroduced with merge

* refactor: rename minusEther to minusBaseUnits

* fix: remove unused setStartedAt

* build: remove unused dependency

src/models/BzzToken.ts

@@ -0,0 +1,8 @@
+import { BigNumber } from 'bignumber.js'
+import { Token } from './Token'
+
+export class BzzToken extends Token {
+  constructor(amount: BigNumber | string | BigInt) {
+    super(amount, 16)
+  }
+}

src/models/DaiToken.ts

@@ -0,0 +1,8 @@
+import { BigNumber } from 'bignumber.js'
+import { Token } from './Token'
+
+export class DaiToken extends Token {
+  constructor(amount: BigNumber | string | BigInt) {
+    super(amount, 18)
+  }
+}

src/models/Token.ts

@@ -13,7 +13,9 @@ export class Token {
   constructor(amount: BigNumber | string | BigInt, decimals: digits = BZZ_DECIMALS) {
     const a = makeBigNumber(amount)
 
-    if (!isInteger(a) || !POSSIBLE_DECIMALS.includes(decimals)) throw new TypeError('Not a valid token values')
+    if (!isInteger(a) || !POSSIBLE_DECIMALS.includes(decimals)) {
+      throw new TypeError(`Not a valid token values: ${amount} ${decimals}`)
+    }
 
     this.amount = a
     this.decimals = decimals
@@ -59,7 +61,7 @@ export class Token {
   }
 
   toSignificantDigits(digits = 4): string {
-    const asString = this.toDecimal.toFixed(16)
+    const asString = this.toDecimal.toFixed(this.decimals)
 
     let indexOfSignificantDigit = -1
     let reachedDecimalPoint = false
@@ -78,4 +80,11 @@ export class Token {
 
     return asString.slice(0, indexOfSignificantDigit + digits)
   }
+
+  minusBaseUnits(amount: string): Token {
+    return new Token(
+      this.toBigNumber.minus(new BigNumber(amount).multipliedBy(new BigNumber(10).pow(this.decimals))),
+      this.decimals,
+    )
+  }
 }