Add progress chart to statistics page showing score progression over time

app/build.gradle.kts

@@ -83,6 +83,9 @@ dependencies {
     implementation("androidx.navigation:navigation-fragment-ktx:2.7.6")
     implementation("androidx.navigation:navigation-ui-ktx:2.7.6")
 
+    // MPAndroidChart for progress visualization
+    implementation("com.github.PhilJay:MPAndroidChart:v3.1.0")
+
     // Room
     implementation("androidx.room:room-runtime:2.6.1")
     implementation("androidx.room:room-ktx:2.6.1")

app/src/main/java/com/accidentalproductions/tetristats/data/ScoreDao.kt

@@ -12,6 +12,9 @@ interface ScoreDao {
     @Query("SELECT * FROM scores WHERE gameVersion = :gameVersion")
     fun getScoresForGame(gameVersion: String): LiveData<List<Score>>
 
+    @Query("SELECT * FROM scores WHERE gameVersion = :gameVersion ORDER BY dateRecorded ASC")
+    fun getScoresForGameByDate(gameVersion: String): LiveData<List<Score>>
+
     @Query("SELECT DISTINCT gameVersion FROM scores")
     fun getGamesWithScores(): LiveData<List<String>>
 

app/src/main/java/com/accidentalproductions/tetristats/ui/stats/StatsFragment.kt

@@ -1,5 +1,6 @@
 package com.accidentalproductions.tetristats.ui.stats
 
+import android.graphics.Color
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
@@ -8,7 +9,16 @@ import android.widget.ArrayAdapter
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
 import androidx.recyclerview.widget.LinearLayoutManager
+import com.accidentalproductions.tetristats.R
 import com.accidentalproductions.tetristats.databinding.FragmentStatsBinding
+import com.github.mikephil.charting.components.XAxis
+import com.github.mikephil.charting.data.Entry
+import com.github.mikephil.charting.data.LineData
+import com.github.mikephil.charting.data.LineDataSet
+import com.github.mikephil.charting.formatter.ValueFormatter
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
 
 class StatsFragment : Fragment() {
     private var _binding: FragmentStatsBinding? = null
@@ -30,6 +40,7 @@ class StatsFragment : Fragment() {
 
         setupRecyclerView()
         setupGameFilter()
+        setupProgressChart()
         observeStats()
     }
 
@@ -53,6 +64,64 @@ class StatsFragment : Fragment() {
         }
     }
     
+    private fun setupProgressChart() {
+        with(binding.chartProgress) {
+            description.isEnabled = false
+            legend.isEnabled = true
+            setTouchEnabled(true)
+            setDrawGridBackground(false)
+            isDragEnabled = true
+            setScaleEnabled(true)
+            setPinchZoom(true)
+            
+            axisRight.isEnabled = false
+            
+            xAxis.position = XAxis.XAxisPosition.BOTTOM
+            xAxis.granularity = 1f
+            xAxis.setDrawGridLines(false)
+            
+            axisLeft.setDrawGridLines(true)
+            axisLeft.axisMinimum = 0f
+        }
+    }
+
+    private fun updateProgressChart(scores: List<Entry>, dates: List<Long>) {
+        if (scores.isEmpty()) {
+            binding.chartProgress.clear()
+            binding.chartProgress.invalidate()
+            return
+        }
+        
+        val dataSet = LineDataSet(scores, "Score Progress").apply {
+            mode = LineDataSet.Mode.CUBIC_BEZIER
+            color = resources.getColor(R.color.tetris_navy, null)
+            lineWidth = 2f
+            setDrawCircles(true)
+            setCircleColor(resources.getColor(R.color.tetris_navy, null))
+            circleRadius = 4f
+            setDrawValues(false)
+            highLightColor = Color.rgb(244, 117, 117)
+        }
+        
+        val lineData = LineData(dataSet)
+        binding.chartProgress.data = lineData
+        
+        // Format X-axis labels (dates)
+        val dateFormat = SimpleDateFormat("MM/dd", Locale.getDefault())
+        binding.chartProgress.xAxis.valueFormatter = object : ValueFormatter() {
+            override fun getFormattedValue(value: Float): String {
+                val index = value.toInt()
+                return if (index >= 0 && index < dates.size) {
+                    dateFormat.format(Date(dates[index]))
+                } else {
+                    ""
+                }
+            }
+        }
+        
+        binding.chartProgress.invalidate()
+    }
+
     private fun observeStats() {
         viewModel.filteredScores.observe(viewLifecycleOwner) { scores ->
             scoreAdapter.submitList(scores)
@@ -65,6 +134,24 @@ class StatsFragment : Fragment() {
         viewModel.highScore.observe(viewLifecycleOwner) { highScore ->
             binding.textViewHighScore.text = "%,d".format(highScore)
         }
+        
+        viewModel.scoresByDate.observe(viewLifecycleOwner) { scores ->
+            // Convert scores to entries for the chart
+            if (scores.isNotEmpty()) {
+                val entries = mutableListOf<Entry>()
+                val dates = mutableListOf<Long>()
+                
+                scores.forEachIndexed { index, score ->
+                    entries.add(Entry(index.toFloat(), score.scoreValue.toFloat()))
+                    dates.add(score.dateRecorded)
+                }
+                
+                updateProgressChart(entries, dates)
+            } else {
+                binding.chartProgress.clear()
+                binding.chartProgress.invalidate()
+            }
+        }
     }
 
     override fun onDestroyView() {

app/src/main/java/com/accidentalproductions/tetristats/ui/stats/StatsViewModel.kt

@@ -18,6 +18,10 @@ class StatsViewModel(application: Application) : AndroidViewModel(application) {
         scoreDao.getScoresForGame(game)
     }
 
+    val scoresByDate: LiveData<List<Score>> = _selectedGame.switchMap { game ->
+        scoreDao.getScoresForGameByDate(game)
+    }
+
     val averageScore: LiveData<Double> = _selectedGame.switchMap { game ->
         scoreDao.getAverageScore(game)
     }

app/src/main/res/layout/fragment_stats.xml

@@ -31,6 +31,33 @@
                 android:inputType="none"/>
         </com.google.android.material.textfield.TextInputLayout>
 
+        <com.google.android.material.card.MaterialCardView
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginBottom="16dp"
+            app:cardCornerRadius="8dp"
+            app:cardElevation="4dp">
+
+            <LinearLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:orientation="vertical"
+                android:padding="16dp">
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="Progress Chart"
+                    android:textAppearance="?attr/textAppearanceSubtitle1" />
+
+                <com.github.mikephil.charting.charts.LineChart
+                    android:id="@+id/chartProgress"
+                    android:layout_width="match_parent"
+                    android:layout_height="200dp"
+                    android:layout_marginTop="8dp" />
+            </LinearLayout>
+        </com.google.android.material.card.MaterialCardView>
+
         <androidx.recyclerview.widget.RecyclerView
             android:id="@+id/recyclerViewScores"
             android:layout_width="match_parent"