Wallet: crypto max decimals (#18267)

* wallet: crypto max decimals

src/status_im/contexts/wallet/common/utils.cljs

@@ -37,6 +37,34 @@
        (map (comp :raw-balance val))
        (reduce money/add)))
 
+(defn extract-exponent
+  [s]
+  (if-let [index (string/index-of s "e")]
+    (subs s (+ index 2))
+    nil))
+
+(defn calc-max-crypto-decimals
+  [value]
+  (let [str-representation   (str value)
+        decimal-part         (second (clojure.string/split str-representation #"\."))
+        exponent             (extract-exponent str-representation)
+        zeroes-count         (count (take-while #(= \0 %) decimal-part))
+        max-decimals         (or exponent zeroes-count)
+        first-non-zero-digit (first (filter #(not (= \0 %)) decimal-part))]
+    (if (= \1 first-non-zero-digit)
+      (inc max-decimals)
+      max-decimals)))
+
+(defn get-standard-crypto-format
+  "For full details: https://github.com/status-im/status-mobile/issues/18225"
+  [{:keys [market-values-per-currency]} token-units]
+  (let [price          (get-in market-values-per-currency [:usd :price])
+        one-cent-value (if (pos? price) (/ 0.01 price) 0)
+        decimals-count (calc-max-crypto-decimals one-cent-value)]
+    (if (< token-units one-cent-value)
+      (str "<" (.toFixed one-cent-value decimals-count))
+      (.toFixed token-units decimals-count))))
+
 (defn total-token-units-in-all-chains
   [{:keys [balances-per-chain decimals] :as _token}]
   (-> balances-per-chain

src/status_im/contexts/wallet/common/utils_test.cljs

@@ -16,3 +16,18 @@
 
       (is (= (utils/get-wallet-qr wallet-singlechain)
              "x000")))))
+
+(deftest test-extract-exponent
+  (testing "extract-exponent function"
+    (is (= (utils/extract-exponent "123.456") nil))
+    (is (= (utils/extract-exponent "2.5e-2") "2"))
+    (is (= (utils/extract-exponent "4.567e-10") "10"))))
+
+(deftest test-calc-max-crypto-decimals
+  (testing "calc-max-crypto-decimals function"
+    (is (= (utils/calc-max-crypto-decimals 0.00323) 2))
+    (is (= (utils/calc-max-crypto-decimals 0.00123) 3))
+    (is (= (utils/calc-max-crypto-decimals 0.00000423) 5))
+    (is (= (utils/calc-max-crypto-decimals 2.23e-6) 5))
+    (is (= (utils/calc-max-crypto-decimals 1.13e-6) 6))))
+

src/status_im/subs/wallet/wallet.cljs

@@ -171,7 +171,11 @@
                                          currency
                                          (get market-values-per-currency
                                               constants/profile-default-currency))
-        {:keys [change-pct-24hour]} market-values]
+        {:keys [change-pct-24hour]} market-values
+        crypto-value                (utils/get-standard-crypto-format token token-units)
+        fiat-value                  (if (string/includes? crypto-value "<")
+                                      "<$0.01"
+                                      (utils/prettify-balance currency-symbol fiat-value))]
     {:token               (:symbol token)
      :token-name          (:name token)
      :state               :default
@@ -180,8 +184,8 @@
                             (neg? change-pct-24hour) :negative
                             :else                    :empty)
      :customization-color color
-     :values              {:crypto-value token-units
-                           :fiat-value   (utils/prettify-balance currency-symbol fiat-value)}}))
+     :values              {:crypto-value crypto-value
+                           :fiat-value   fiat-value}}))
 
 (rf/reg-sub
  :wallet/account-token-values