Initial commit

SatsPrice/SatsViewModel.swift

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+//
+//  SatsViewModel.swift
+//  SatsPrice
+//
+//  Created by Terry Yiu on 2/19/24.
+//
+
+import Foundation
+import BigDecimal
+
+class SatsViewModel: ObservableObject {
+    @Published private(set) var btcToUsd: BigDecimal = BigDecimal.nan
+    @Published var lastUpdated: Date = Date.now
+
+    @Published private(set) var sats: BigDecimal = 0
+    @Published private(set) var btc: BigDecimal = 0
+    @Published private(set) var usd: BigDecimal = 0
+
+    var btcToUsdString: String {
+        get { btcToUsd.asString(.plain) }
+        set {
+            self.btcToUsd = BigDecimal(newValue)
+            self.usd = btc.multiply(btcToUsd, Rounding(.down, 20))
+        }
+    }
+
+    var satsString: String {
+        get { sats.asString(.plain) }
+        set {
+            self.sats = BigDecimal(newValue)
+
+            let preciseDivide = sats.divide(100000000)
+            if preciseDivide.isNaN {
+                self.btc = sats.divide(100000000, Rounding(.down, 20))
+            } else {
+                self.btc = sats.divide(100000000)
+            }
+
+            self.usd = btc.multiply(btcToUsd, Rounding(.down, 20))
+        }
+    }
+
+    var btcString: String {
+        get { btc.asString(.plain) }
+        set {
+            self.btc = BigDecimal(newValue)
+            self.sats = btc.multiply(100000000, Rounding(.down, 20))
+            self.usd = btc.multiply(btcToUsd, Rounding(.down, 20))
+        }
+    }
+
+    var usdString: String {
+        get { usd.asString(.plain) }
+        set {
+            self.usd = BigDecimal(newValue)
+
+            let preciseDivide = usd.divide(btcToUsd)
+            if preciseDivide.isNaN {
+                self.btc = usd.divide(btcToUsd, Rounding(.down, 20))
+            } else {
+                self.btc = usd.divide(btcToUsd)
+            }
+
+            self.sats = btc.multiply(100000000, Rounding(.down, 20))
+        }
+    }
+}