✨ Add Moving Average Graph to "All Time" chart

Closes #776

Signed-off-by: Leonardo Colman Lopes <[email protected]>

Author: LeoColman

app/src/main/kotlin/br/com/colman/petals/statistics/graph/AllTimeGraph.kt

@@ -4,7 +4,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.res.stringResource
 import br.com.colman.petals.R.string.grams_distribution_over_days_since_first_use
 import br.com.colman.petals.statistics.graph.component.LineChart
-import br.com.colman.petals.statistics.graph.data.createAllTimeDistribution
+import br.com.colman.petals.statistics.graph.data.createAllTimeDistributionWithMovingAverage
 import br.com.colman.petals.statistics.graph.formatter.DaysSinceFirstUseFormatter
 import br.com.colman.petals.use.repository.Use
 import com.github.mikephil.charting.components.LimitLine
@@ -13,10 +13,10 @@ import java.time.YearMonth
 @Composable
 fun AllTimeGraph(uses: List<Use>, dateFormat: String) {
   val description = stringResource(grams_distribution_over_days_since_first_use)
-  val gramsData = createAllTimeDistribution(uses)
+  val gramsData = createAllTimeDistributionWithMovingAverage(uses)
   val gramsDataList = listOf(gramsData)
 
-  LineChart(gramsDataList, description, 5f) {
+  LineChart(gramsDataList.flatten(), description, 5f) {
     axisMinimum = 1f
     labelCount = 5
     granularity = 1f

app/src/main/kotlin/br/com/colman/petals/statistics/graph/data/DistributionPerDaySinceFirstUse.kt

@@ -5,6 +5,7 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.Color.Companion.Gray
 import androidx.compose.ui.graphics.toArgb
 import androidx.compose.ui.res.stringResource
+import br.com.colman.petals.R
 import br.com.colman.petals.R.string.grams_distribution_over_days_since_first_use
 import br.com.colman.petals.statistics.graph.formatter.GramsValueFormatter
 import br.com.colman.petals.use.repository.Use
@@ -14,25 +15,41 @@ import java.math.BigDecimal
 import java.time.LocalDate.now
 
 @Composable
-fun createAllTimeDistribution(uses: List<Use>): LineDataSet {
-  val label = stringResource(grams_distribution_over_days_since_first_use)
-  return createAllTimeLineDataSet(calculateAllTimeGramsDistribution(uses), label)
+fun createAllTimeDistributionWithMovingAverage(uses: List<Use>): List<LineDataSet> {
+  val gramsLabel = stringResource(grams_distribution_over_days_since_first_use)
+  val gramsDataSet = createAllTimeLineDataSet(calculateAllTimeGramsDistribution(uses), gramsLabel)
+
+  val movingAverageLabel = stringResource(R.string.moving_average_grams_distribution)
+  val movingAverageDataSet = createAllTimeAverageDataSet(
+    calculateMovingAverage(calculateAllTimeGramsDistribution(uses)),
+    movingAverageLabel
+  )
+
+  return listOf(gramsDataSet, movingAverageDataSet)
 }
 
 fun createAllTimeLineDataSet(entryList: List<Entry>, label: String): LineDataSet {
   return LineDataSet(entryList, label).apply {
     valueFormatter = GramsValueFormatter
     lineWidth = 6f
-    setDrawCircles(true)
     setDrawFilled(true)
-    setDrawValues(true)
+    setDrawCircles(false)
     fillColor = Color.Cyan.copy(alpha = 0.3f).toArgb()
     color = Color.Cyan.toArgb()
     valueTextColor = Gray.toArgb()
     valueTextSize = 14f
   }
 }
 
+fun createAllTimeAverageDataSet(entryList: List<Entry>, label: String): LineDataSet {
+  return LineDataSet(entryList, label).apply {
+    setDrawValues(false)
+    setDrawCircles(false)
+    lineWidth = 6f
+    color = Color.Green.toArgb()
+  }
+}
+
 private fun calculateAllTimeGramsDistribution(uses: List<Use>): List<Entry> {
   if (uses.isEmpty()) return emptyList()
 
@@ -46,3 +63,18 @@ private fun calculateAllTimeGramsDistribution(uses: List<Use>): List<Entry> {
     Entry((day - firstUseDay).toFloat(), totalGrams.toFloat())
   }
 }
+
+private fun calculateMovingAverage(entries: List<Entry>): List<Entry> {
+  if (entries.isEmpty()) return emptyList()
+
+  val result = mutableListOf<Entry>()
+  for (i in entries.indices) {
+    val start = maxOf(0, i - 14 + 1)
+    val end = i + 1
+    val windowEntries = entries.subList(start, end)
+
+    val averageValue = windowEntries.map { it.y }.average().toFloat()
+    result.add(Entry(entries[i].x, averageValue))
+  }
+  return result
+}

app/src/main/res/values/strings.xml

@@ -172,11 +172,12 @@
     <string name="no_break_period">No break period</string>
     <string name="hours_12">12 hours</string>
     <string name="hours_24">24 hours</string>
-    <string name="grams_distribution_over_days_since_first_use">Grams distribution over days since first use</string>
+    <string name="grams_distribution_over_days_since_first_use">Grams per Day</string>
     <plurals name="last_x_days">
         <item quantity="one">Last %s day</item>
         <item quantity="other">Last %s days</item>
     </plurals>
 	<string name="language_label">App language</string>
 	<string name="what_language_should_be_used">What language should be used</string>
+    <string name="moving_average_grams_distribution">Average Grams per Day</string>
 </resources>