Updated on 2026-08-14

core/datasource/src/main/java/com/tangem/datasource/api/markets/models/response/TokenMarketChartResponse.kt

@@ -6,6 +6,8 @@ import java.math.BigDecimal
 
 @JsonClass(generateAdapter = true)
 data class TokenMarketChartResponse(
+    // There is a bug in the API, it returns null values.
+    // We need to filter them out.
     @Json(name = "prices")
-    val prices: Map<Long, BigDecimal>,
+    val prices: Map<Long, BigDecimal?>,
 )

data/markets/src/main/java/com/tangem/data/markets/DefaultMarketsTokenRepository.kt

@@ -103,6 +103,7 @@ internal class DefaultMarketsTokenRepository(
         val tokenMarketsUpdateFetcher = MarketsBatchUpdateFetcher(
             tangemTechApi = tangemTechApi,
             marketsApi = marketsApi,
+            analyticsEventHandler = analyticsEventHandler,
             onApiError = {
                 analyticsEventHandler.send(MarketsDataAnalyticsEvent.List.Error.toEvent())
             },
@@ -141,7 +142,19 @@ internal class DefaultMarketsTokenRepository(
             response.getOrThrow()
         }
 
-        return TokenChartConverter.convert(interval, result)
+        return TokenChartConverter.convert(
+            interval = interval,
+            value = result,
+
+            // === Analytics ===
+            onNullPresented = {
+                analyticsEventHandler.send(
+                    MarketsDataAnalyticsEvent.ChartNullValuesError(
+                        requestPath = "coins/history",
+                    ),
+                )
+            },
+        )
     }
 
     override suspend fun getChartPreview(
@@ -163,7 +176,19 @@ internal class DefaultMarketsTokenRepository(
             )
         }
 
-        return TokenChartConverter.convert(interval, chart)
+        return TokenChartConverter.convert(
+            interval = interval,
+            value = chart,
+
+            // === Analytics ===
+            onNullPresented = {
+                analyticsEventHandler.send(
+                    MarketsDataAnalyticsEvent.ChartNullValuesError(
+                        requestPath = "coins/history_preview",
+                    ),
+                )
+            },
+        )
     }
 
     override suspend fun getTokenInfo(

data/markets/src/main/java/com/tangem/data/markets/MarketsBatchUpdateFetcher.kt

@@ -1,6 +1,8 @@
 package com.tangem.data.markets
 
+import com.tangem.core.analytics.api.AnalyticsEventHandler
 import com.tangem.data.common.utils.retryOnError
+import com.tangem.data.markets.analytics.MarketsDataAnalyticsEvent
 import com.tangem.data.markets.converters.TokenMarketChartsConverter
 import com.tangem.data.markets.converters.TokenQuotesShortConverter
 import com.tangem.data.markets.converters.toRequestParam
@@ -22,6 +24,7 @@ import kotlinx.coroutines.launch
 internal class MarketsBatchUpdateFetcher(
     private val marketsApi: TangemTechMarketsApi,
     private val tangemTechApi: TangemTechApi,
+    private val analyticsEventHandler: AnalyticsEventHandler,
     private val onApiError: () -> Unit,
 ) : BatchUpdateFetcher<Int, List<TokenMarket>, TokenMarketUpdateRequest> {
 
@@ -52,6 +55,7 @@ internal class MarketsBatchUpdateFetcher(
                 updateTasks.forEachIndexed { index, deferred ->
                     launch {
                         val res = deferred.await()
+                        checkForNulls(res)
                         val batchToUpdate = toUpdate[index]
 
                         update {
@@ -113,6 +117,22 @@ internal class MarketsBatchUpdateFetcher(
         )
     }
 
+    private fun checkForNulls(response: TokenMarketChartListResponse) {
+        response.values.forEach { chart ->
+            chart.prices.forEach { (_, price) ->
+                if (price == null) {
+                    analyticsEventHandler.send(
+                        MarketsDataAnalyticsEvent.ChartNullValuesError(
+                            requestPath = "coins/history_preview",
+                        ),
+                    )
+
+                    return
+                }
+            }
+        }
+    }
+
     private inline fun <T> catchApiError(onError: () -> Unit, block: () -> T): T {
         return try {
             block()

data/markets/src/main/java/com/tangem/data/markets/analytics/MarketsDataAnalyticsEvent.kt

@@ -36,7 +36,20 @@ sealed interface MarketsDataAnalyticsEvent {
     }
 
     fun toEvent(): AnalyticsEvent = when (this) {
+        is ChartNullValuesError -> this
         is List -> this
         is Details -> this
     }
+
+    data class ChartNullValuesError(
+        val requestPath: String,
+    ) : AnalyticsEvent(
+        category = "Markets / Chart",
+        event = "Data Error",
+        params = mapOf("Request path" to requestPath),
+        error = IllegalStateException(
+            "Chart data contains null values from the API",
+        ),
+    ),
+        MarketsDataAnalyticsEvent
 }

data/markets/src/main/java/com/tangem/data/markets/converters/TokenChartConverter.kt

@@ -6,11 +6,21 @@ import com.tangem.domain.markets.TokenChart
 
 internal object TokenChartConverter {
 
-    fun convert(interval: PriceChangeInterval, value: TokenMarketChartResponse): TokenChart {
+    fun convert(
+        interval: PriceChangeInterval,
+        value: TokenMarketChartResponse,
+        onNullPresented: () -> Unit = {},
+    ): TokenChart {
+        val points = value.prices.mapNotNull { p -> p.value?.let { p.key to it } }.toMap()
+
+        if (points.size < points.values.size) {
+            onNullPresented()
+        }
+
         return TokenChart(
             interval = interval,
-            priceY = value.prices.values.toList(),
+            priceY = points.values.toList(),
-            timeStamps = value.prices.keys.toList(),
+            timeStamps = points.keys.toList(),
         )
     }
 }