Add sleep tracking, statistics module and backup features

Features:
- Sleep tracking with timer and manual duration input
- Statistics module with 5 tabs (daily summary, feeding, diapers, sleep, growth)
- Export/Import backup functionality in settings
- Complete German, French and Italian translations

app/src/main/java/it/danieleverducci/lunatracker/MainActivity.kt

@@ -76,6 +76,12 @@ class MainActivity : AppCompatActivity() {
     var bfTimerHandler: Handler? = null
     var bfTimerRunnable: Runnable? = null
 
+    // Sleep timer state
+    var sleepTimerStartTime: Long = 0
+    var sleepTimerDialog: AlertDialog? = null
+    var sleepTimerHandler: Handler? = null
+    var sleepTimerRunnable: Runnable? = null
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
@@ -134,6 +140,9 @@ class MainActivity : AppCompatActivity() {
         findViewById<View>(R.id.button_settings).setOnClickListener {
             showSettings()
         }
+        findViewById<View>(R.id.button_statistics).setOnClickListener {
+            showStatistics()
+        }
         findViewById<View>(R.id.button_no_connection_retry).setOnClickListener {
             // This may happen at start, when logbook is still null: better ask the logbook list
             loadLogbookList()
@@ -164,6 +173,12 @@ class MainActivity : AppCompatActivity() {
         startActivity(i)
     }
 
+    fun showStatistics() {
+        val i = Intent(this, StatisticsActivity::class.java)
+        i.putExtra(StatisticsActivity.EXTRA_LOGBOOK_NAME, logbook?.name ?: "")
+        startActivity(i)
+    }
+
     fun showLogbook() {
         // Show logbook
         if (logbook == null)
@@ -204,6 +219,9 @@ class MainActivity : AppCompatActivity() {
         // Check for ongoing breastfeeding timer
         restoreBreastfeedingTimerIfNeeded()
 
+        // Check for ongoing sleep timer
+        restoreSleepTimerIfNeeded()
+
         if (logbook != null) {
             // Already running: reload data for currently selected logbook
             loadLogbook(logbook!!.name)
@@ -220,6 +238,10 @@ class MainActivity : AppCompatActivity() {
         bfTimerRunnable?.let { bfTimerHandler?.removeCallbacks(it) }
         bfTimerDialog?.dismiss()
 
+        // Clean up sleep timer UI (state is preserved in SharedPreferences)
+        sleepTimerRunnable?.let { sleepTimerHandler?.removeCallbacks(it) }
+        sleepTimerDialog?.dismiss()
+
         super.onStop()
     }
 
@@ -452,6 +474,117 @@ class MainActivity : AppCompatActivity() {
         }
     }
 
+    // Sleep timer methods
+    fun startSleepTimer() {
+        // Check if timer already running
+        if (sleepTimerStartTime > 0) {
+            Toast.makeText(this, R.string.sleep_timer_already_running, Toast.LENGTH_SHORT).show()
+            return
+        }
+
+        // Save timer state
+        sleepTimerStartTime = System.currentTimeMillis()
+        saveSleepTimerState()
+
+        // Show timer dialog
+        showSleepTimerDialog()
+    }
+
+    fun showSleepTimerDialog() {
+        val d = AlertDialog.Builder(this)
+        val dialogView = layoutInflater.inflate(R.layout.sleep_timer_dialog, null)
+        d.setTitle(R.string.sleep_timer_title)
+        d.setView(dialogView)
+        d.setCancelable(false)
+
+        val timerDisplay = dialogView.findViewById<TextView>(R.id.sleep_timer_display)
+
+        // Set up timer updates
+        sleepTimerHandler = Handler(mainLooper)
+        sleepTimerRunnable = object : Runnable {
+            override fun run() {
+                val elapsed = (System.currentTimeMillis() - sleepTimerStartTime) / 1000
+                val hours = elapsed / 3600
+                val minutes = (elapsed % 3600) / 60
+                val seconds = elapsed % 60
+                timerDisplay.text = if (hours > 0) {
+                    String.format("%d:%02d:%02d", hours, minutes, seconds)
+                } else {
+                    String.format("%02d:%02d", minutes, seconds)
+                }
+                sleepTimerHandler?.postDelayed(this, 1000)
+            }
+        }
+        sleepTimerHandler?.post(sleepTimerRunnable!!)
+
+        d.setPositiveButton(R.string.sleep_timer_stop) { _, _ ->
+            stopSleepTimer()
+        }
+        d.setNegativeButton(android.R.string.cancel) { dialogInterface, _ ->
+            cancelSleepTimer()
+            dialogInterface.dismiss()
+        }
+
+        sleepTimerDialog = d.create()
+        sleepTimerDialog?.show()
+    }
+
+    fun stopSleepTimer() {
+        sleepTimerHandler?.removeCallbacks(sleepTimerRunnable!!)
+
+        val durationMillis = System.currentTimeMillis() - sleepTimerStartTime
+        val durationMinutes = Math.max(1, (durationMillis / 60000).toInt()) // Minimum 1 minute
+
+        clearSleepTimerState()
+
+        logEvent(LunaEvent(LunaEvent.TYPE_SLEEP, durationMinutes))
+    }
+
+    fun cancelSleepTimer() {
+        sleepTimerHandler?.removeCallbacks(sleepTimerRunnable!!)
+        clearSleepTimerState()
+    }
+
+    fun askSleepDuration() {
+        val d = AlertDialog.Builder(this)
+        val dialogView = layoutInflater.inflate(R.layout.sleep_duration_dialog, null)
+        d.setTitle(R.string.sleep_duration_title)
+        d.setMessage(R.string.sleep_duration_description)
+        d.setView(dialogView)
+
+        val numberPicker = dialogView.findViewById<NumberPicker>(R.id.sleep_duration_picker)
+        numberPicker.minValue = 1
+        numberPicker.maxValue = 180  // Up to 3 hours
+        numberPicker.value = 30  // Default 30 minutes
+        numberPicker.wrapSelectorWheel = false
+
+        d.setPositiveButton(android.R.string.ok) { _, _ ->
+            logEvent(LunaEvent(LunaEvent.TYPE_SLEEP, numberPicker.value))
+        }
+        d.setNegativeButton(android.R.string.cancel) { dialogInterface, _ ->
+            dialogInterface.dismiss()
+        }
+        d.create().show()
+    }
+
+    fun saveSleepTimerState() {
+        LocalSettingsRepository(this).saveSleepTimer(sleepTimerStartTime)
+    }
+
+    fun clearSleepTimerState() {
+        sleepTimerStartTime = 0
+        sleepTimerDialog = null
+        LocalSettingsRepository(this).clearSleepTimer()
+    }
+
+    fun restoreSleepTimerIfNeeded() {
+        val startTime = LocalSettingsRepository(this).loadSleepTimer()
+        if (startTime > 0) {
+            sleepTimerStartTime = startTime
+            showSleepTimerDialog()
+        }
+    }
+
     fun askToTrimLogbook() {
         val d = AlertDialog.Builder(this)
         d.setTitle(R.string.trim_logbook_dialog_title)
@@ -539,24 +672,32 @@ class MainActivity : AppCompatActivity() {
             }, startYear, startMonth, startDay).show()
         }
 
-        // Make quantity editable for breastfeeding events
+        // Make quantity editable for breastfeeding and sleep events
         val quantityTextView = dialogView.findViewById<TextView>(R.id.dialog_event_detail_type_quantity)
-        if (event.type in listOf(
+        val isBreastfeeding = event.type in listOf(
             LunaEvent.TYPE_BREASTFEEDING_LEFT_NIPPLE,
             LunaEvent.TYPE_BREASTFEEDING_BOTH_NIPPLE,
             LunaEvent.TYPE_BREASTFEEDING_RIGHT_NIPPLE
-        ) && event.quantity > 0) {
+        )
+        val isSleep = event.type == LunaEvent.TYPE_SLEEP
+        if ((isBreastfeeding || isSleep) && event.quantity > 0) {
             quantityTextView.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_edit, 0)
             quantityTextView.compoundDrawableTintList = ColorStateList.valueOf(getColor(R.color.accent))
             quantityTextView.setOnClickListener {
                 val pickerDialog = AlertDialog.Builder(this@MainActivity)
-                val pickerView = layoutInflater.inflate(R.layout.breastfeeding_duration_dialog, null)
-                val picker = pickerView.findViewById<NumberPicker>(R.id.breastfeeding_duration_picker)
+                val pickerView = if (isSleep) {
+                    layoutInflater.inflate(R.layout.sleep_duration_dialog, null)
+                } else {
+                    layoutInflater.inflate(R.layout.breastfeeding_duration_dialog, null)
+                }
+                val picker = pickerView.findViewById<NumberPicker>(
+                    if (isSleep) R.id.sleep_duration_picker else R.id.breastfeeding_duration_picker
+                )
                 picker.minValue = 1
-                picker.maxValue = 60
-                picker.value = if (event.quantity > 0) event.quantity else 15
+                picker.maxValue = if (isSleep) 180 else 60
+                picker.value = if (event.quantity > 0) Math.min(event.quantity, picker.maxValue) else if (isSleep) 30 else 15
 
-                pickerDialog.setTitle(R.string.breastfeeding_duration_title)
+                pickerDialog.setTitle(if (isSleep) R.string.sleep_duration_title else R.string.breastfeeding_duration_title)
                 pickerDialog.setView(pickerView)
                 pickerDialog.setPositiveButton(android.R.string.ok) { _, _ ->
                     event.quantity = picker.value
@@ -971,6 +1112,15 @@ class MainActivity : AppCompatActivity() {
             isOutsideTouchable = true
             val inflater = LayoutInflater.from(anchor.context)
             contentView = inflater.inflate(R.layout.more_events_popup, null)
+            contentView.findViewById<View>(R.id.button_sleep).setOnClickListener {
+                startSleepTimer()
+                dismiss()
+            }
+            contentView.findViewById<View>(R.id.button_sleep).setOnLongClickListener {
+                askSleepDuration()
+                dismiss()
+                true
+            }
             contentView.findViewById<View>(R.id.button_medicine).setOnClickListener {
                 askNotes(LunaEvent(LunaEvent.TYPE_MEDICINE))
                 dismiss()

app/src/main/java/it/danieleverducci/lunatracker/SettingsActivity.kt

@@ -1,20 +1,26 @@
 package it.danieleverducci.lunatracker
 
+import android.net.Uri
 import android.os.Bundle
 import android.view.View
 import android.widget.EditText
 import android.widget.RadioButton
 import android.widget.TextView
 import android.widget.Toast
+import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.AppCompatActivity
 import com.google.android.material.progressindicator.LinearProgressIndicator
 import com.google.android.material.switchmaterial.SwitchMaterial
 import com.thegrizzlylabs.sardineandroid.impl.SardineException
+import it.danieleverducci.lunatracker.entities.Logbook
+import it.danieleverducci.lunatracker.entities.LunaEvent
 import it.danieleverducci.lunatracker.repository.FileLogbookRepository
 import it.danieleverducci.lunatracker.repository.LocalSettingsRepository
 import it.danieleverducci.lunatracker.repository.LogbookListObtainedListener
 import it.danieleverducci.lunatracker.repository.WebDAVLogbookRepository
 import okio.IOException
+import org.json.JSONArray
+import org.json.JSONObject
 
 open class SettingsActivity : AppCompatActivity() {
     protected lateinit var settingsRepository: LocalSettingsRepository
@@ -27,6 +33,15 @@ open class SettingsActivity : AppCompatActivity() {
     protected lateinit var switchNoBreastfeeding: SwitchMaterial
     protected lateinit var textViewSignature: EditText
 
+    // Activity Result Launchers for Export/Import
+    private val exportLauncher = registerForActivityResult(
+        ActivityResultContracts.CreateDocument("application/json")
+    ) { uri -> uri?.let { exportLogbookToUri(it) } }
+
+    private val importLauncher = registerForActivityResult(
+        ActivityResultContracts.OpenDocument()
+    ) { uri -> uri?.let { importLogbookFromUri(it) } }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
@@ -46,6 +61,12 @@ open class SettingsActivity : AppCompatActivity() {
         findViewById<View>(R.id.settings_cancel).setOnClickListener({
             finish()
         })
+        findViewById<View>(R.id.settings_export).setOnClickListener({
+            startExport()
+        })
+        findViewById<View>(R.id.settings_import).setOnClickListener({
+            startImport()
+        })
 
         settingsRepository = LocalSettingsRepository(this)
         loadSettings()
@@ -198,4 +219,136 @@ open class SettingsActivity : AppCompatActivity() {
         fun onCopyLocalLogbooksToWebdavFinished(errors: String?)
     }
 
+    // Export/Import functionality
+    private fun startExport() {
+        val timestamp = java.text.SimpleDateFormat("yyyyMMdd_HHmmss", java.util.Locale.US)
+            .format(java.util.Date())
+        exportLauncher.launch("lunatracker_backup_$timestamp.json")
+    }
+
+    private fun startImport() {
+        importLauncher.launch(arrayOf("application/json"))
+    }
+
+    private fun exportLogbookToUri(uri: Uri) {
+        progressIndicator.visibility = View.VISIBLE
+        Thread {
+            try {
+                val fileLogbookRepo = FileLogbookRepository()
+                val logbooks = fileLogbookRepo.getAllLogbooks(this)
+
+                val json = JSONObject().apply {
+                    put("version", 1)
+                    put("app", "LunaTracker")
+                    put("exported_at", System.currentTimeMillis())
+                    put("logbooks", JSONArray().apply {
+                        logbooks.forEach { logbook ->
+                            put(JSONObject().apply {
+                                put("name", logbook.name)
+                                put("events", JSONArray().apply {
+                                    logbook.logs.forEach { event ->
+                                        put(event.toJson())
+                                    }
+                                })
+                            })
+                        }
+                    })
+                }
+
+                contentResolver.openOutputStream(uri)?.use { outputStream ->
+                    outputStream.write(json.toString(2).toByteArray(Charsets.UTF_8))
+                }
+
+                val eventCount = logbooks.sumOf { it.logs.size }
+                runOnUiThread {
+                    progressIndicator.visibility = View.INVISIBLE
+                    Toast.makeText(
+                        this,
+                        getString(R.string.export_success, eventCount),
+                        Toast.LENGTH_SHORT
+                    ).show()
+                }
+            } catch (e: Exception) {
+                runOnUiThread {
+                    progressIndicator.visibility = View.INVISIBLE
+                    Toast.makeText(
+                        this,
+                        getString(R.string.export_error) + e.message,
+                        Toast.LENGTH_SHORT
+                    ).show()
+                }
+            }
+        }.start()
+    }
+
+    private fun importLogbookFromUri(uri: Uri) {
+        progressIndicator.visibility = View.VISIBLE
+        Thread {
+            try {
+                val jsonString = contentResolver.openInputStream(uri)?.bufferedReader()?.readText()
+                    ?: throw Exception("Could not read file")
+
+                val json = JSONObject(jsonString)
+                val version = json.optInt("version", 1)
+
+                val fileLogbookRepo = FileLogbookRepository()
+                var totalEvents = 0
+
+                if (json.has("logbooks")) {
+                    // New format with multiple logbooks
+                    val logbooksArray = json.getJSONArray("logbooks")
+                    for (i in 0 until logbooksArray.length()) {
+                        val logbookJson = logbooksArray.getJSONObject(i)
+                        val name = logbookJson.optString("name", "")
+                        val eventsArray = logbookJson.getJSONArray("events")
+
+                        val logbook = Logbook(name)
+                        for (j in 0 until eventsArray.length()) {
+                            try {
+                                logbook.logs.add(LunaEvent(eventsArray.getJSONObject(j)))
+                                totalEvents++
+                            } catch (e: IllegalArgumentException) {
+                                // Skip invalid events
+                            }
+                        }
+                        fileLogbookRepo.saveLogbook(this, logbook)
+                    }
+                } else if (json.has("events")) {
+                    // Old format with single logbook
+                    val name = json.optString("logbook_name", "")
+                    val eventsArray = json.getJSONArray("events")
+
+                    val logbook = Logbook(name)
+                    for (i in 0 until eventsArray.length()) {
+                        try {
+                            logbook.logs.add(LunaEvent(eventsArray.getJSONObject(i)))
+                            totalEvents++
+                        } catch (e: IllegalArgumentException) {
+                            // Skip invalid events
+                        }
+                    }
+                    fileLogbookRepo.saveLogbook(this, logbook)
+                }
+
+                runOnUiThread {
+                    progressIndicator.visibility = View.INVISIBLE
+                    Toast.makeText(
+                        this,
+                        getString(R.string.import_success, totalEvents),
+                        Toast.LENGTH_SHORT
+                    ).show()
+                }
+            } catch (e: Exception) {
+                runOnUiThread {
+                    progressIndicator.visibility = View.INVISIBLE
+                    Toast.makeText(
+                        this,
+                        getString(R.string.import_error) + ": " + e.message,
+                        Toast.LENGTH_LONG
+                    ).show()
+                }
+            }
+        }.start()
+    }
+
 }

app/src/main/java/it/danieleverducci/lunatracker/StatisticsActivity.kt

@@ -0,0 +1,207 @@
+package it.danieleverducci.lunatracker
+
+import android.os.Bundle
+import android.util.Log
+import android.view.View
+import android.widget.AdapterView
+import android.widget.ArrayAdapter
+import android.widget.ImageView
+import android.widget.Spinner
+import android.widget.TextView
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentActivity
+import androidx.viewpager2.adapter.FragmentStateAdapter
+import androidx.viewpager2.widget.ViewPager2
+import com.google.android.material.tabs.TabLayout
+import com.google.android.material.tabs.TabLayoutMediator
+import com.thegrizzlylabs.sardineandroid.impl.SardineException
+import it.danieleverducci.lunatracker.entities.Logbook
+import it.danieleverducci.lunatracker.entities.LunaEvent
+import it.danieleverducci.lunatracker.fragments.DailySummaryFragment
+import it.danieleverducci.lunatracker.fragments.DiaperStatsFragment
+import it.danieleverducci.lunatracker.fragments.FeedingStatsFragment
+import it.danieleverducci.lunatracker.fragments.GrowthStatsFragment
+import it.danieleverducci.lunatracker.fragments.SleepStatsFragment
+import it.danieleverducci.lunatracker.repository.FileLogbookRepository
+import it.danieleverducci.lunatracker.repository.LocalSettingsRepository
+import it.danieleverducci.lunatracker.repository.LogbookLoadedListener
+import it.danieleverducci.lunatracker.repository.LogbookRepository
+import it.danieleverducci.lunatracker.repository.WebDAVLogbookRepository
+import okio.IOException
+import org.json.JSONException
+import utils.StatisticsCalculator
+
+class StatisticsActivity : AppCompatActivity() {
+
+    companion object {
+        const val TAG = "StatisticsActivity"
+        const val EXTRA_LOGBOOK_NAME = "logbook_name"
+    }
+
+    private lateinit var viewPager: ViewPager2
+    private lateinit var tabLayout: TabLayout
+    private lateinit var periodSpinner: Spinner
+
+    private var events: List<LunaEvent> = emptyList()
+    private var selectedPeriod: Int = 7 // Default 7 days
+    private var logbookName: String = ""
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_statistics)
+
+        // Back button
+        findViewById<ImageView>(R.id.button_back).setOnClickListener {
+            finish()
+        }
+
+        // Title with logbook name
+        logbookName = intent.getStringExtra(EXTRA_LOGBOOK_NAME) ?: ""
+        if (logbookName.isNotEmpty()) {
+            findViewById<TextView>(R.id.statistics_title).text =
+                "${getString(R.string.statistics_title)} - $logbookName"
+        }
+
+        // Period spinner
+        periodSpinner = findViewById(R.id.period_spinner)
+        val periods = arrayOf(
+            getString(R.string.stats_period_7days),
+            getString(R.string.stats_period_14days),
+            getString(R.string.stats_period_30days)
+        )
+        val periodAdapter = ArrayAdapter(this, android.R.layout.simple_spinner_item, periods)
+        periodAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
+        periodSpinner.adapter = periodAdapter
+        periodSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
+            override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
+                selectedPeriod = when (position) {
+                    0 -> 7
+                    1 -> 14
+                    2 -> 30
+                    else -> 7
+                }
+                notifyFragmentsOfPeriodChange()
+            }
+
+            override fun onNothingSelected(parent: AdapterView<*>?) {}
+        }
+
+        // ViewPager and TabLayout
+        viewPager = findViewById(R.id.view_pager)
+        tabLayout = findViewById(R.id.tab_layout)
+
+        // Load events
+        loadEvents()
+    }
+
+    private fun loadEvents() {
+        val settingsRepo = LocalSettingsRepository(this)
+        val repository: LogbookRepository = when (settingsRepo.loadDataRepository()) {
+            LocalSettingsRepository.DATA_REPO.WEBDAV -> {
+                val credentials = settingsRepo.loadWebdavCredentials()
+                if (credentials != null) {
+                    WebDAVLogbookRepository(credentials[0], credentials[1], credentials[2])
+                } else {
+                    FileLogbookRepository()
+                }
+            }
+            LocalSettingsRepository.DATA_REPO.LOCAL_FILE -> FileLogbookRepository()
+        }
+
+        repository.loadLogbook(this, logbookName, object : LogbookLoadedListener {
+            override fun onLogbookLoaded(logbook: Logbook) {
+                runOnUiThread {
+                    events = logbook.logs
+                    setupViewPager()
+                }
+            }
+
+            override fun onIOError(error: IOException) {
+                Log.e(TAG, "IO error loading logbook", error)
+                runOnUiThread {
+                    events = emptyList()
+                    setupViewPager()
+                }
+            }
+
+            override fun onWebDAVError(error: SardineException) {
+                Log.e(TAG, "WebDAV error loading logbook", error)
+                runOnUiThread {
+                    events = emptyList()
+                    setupViewPager()
+                }
+            }
+
+            override fun onJSONError(error: JSONException) {
+                Log.e(TAG, "JSON error loading logbook", error)
+                runOnUiThread {
+                    events = emptyList()
+                    setupViewPager()
+                }
+            }
+
+            override fun onError(error: Exception) {
+                Log.e(TAG, "Error loading logbook", error)
+                runOnUiThread {
+                    events = emptyList()
+                    setupViewPager()
+                }
+            }
+        })
+    }
+
+    private fun setupViewPager() {
+        val adapter = StatisticsPagerAdapter(this)
+        viewPager.adapter = adapter
+
+        TabLayoutMediator(tabLayout, viewPager) { tab, position ->
+            tab.text = when (position) {
+                0 -> getString(R.string.stats_tab_today)
+                1 -> getString(R.string.stats_tab_feeding)
+                2 -> getString(R.string.stats_tab_diapers)
+                3 -> getString(R.string.stats_tab_sleep)
+                4 -> getString(R.string.stats_tab_growth)
+                else -> ""
+            }
+        }.attach()
+    }
+
+    private fun notifyFragmentsOfPeriodChange() {
+        if (events.isEmpty()) return
+
+        // Force fragment refresh by recreating adapter
+        val currentItem = viewPager.currentItem
+        viewPager.adapter = StatisticsPagerAdapter(this)
+        viewPager.setCurrentItem(currentItem, false)
+        TabLayoutMediator(tabLayout, viewPager) { tab, position ->
+            tab.text = when (position) {
+                0 -> getString(R.string.stats_tab_today)
+                1 -> getString(R.string.stats_tab_feeding)
+                2 -> getString(R.string.stats_tab_diapers)
+                3 -> getString(R.string.stats_tab_sleep)
+                4 -> getString(R.string.stats_tab_growth)
+                else -> ""
+            }
+        }.attach()
+    }
+
+    fun getEvents(): List<LunaEvent> = events
+    fun getSelectedPeriod(): Int = selectedPeriod
+    fun getCalculator(): StatisticsCalculator = StatisticsCalculator(events)
+
+    private inner class StatisticsPagerAdapter(fa: FragmentActivity) : FragmentStateAdapter(fa) {
+        override fun getItemCount(): Int = 5
+
+        override fun createFragment(position: Int): Fragment {
+            return when (position) {
+                0 -> DailySummaryFragment()
+                1 -> FeedingStatsFragment()
+                2 -> DiaperStatsFragment()
+                3 -> SleepStatsFragment()
+                4 -> GrowthStatsFragment()
+                else -> DailySummaryFragment()
+            }
+        }
+    }
+}

app/src/main/java/it/danieleverducci/lunatracker/entities/LunaEvent.kt

@@ -30,6 +30,7 @@ class LunaEvent: Comparable<LunaEvent> {
         const val TYPE_FOOD = "FOOD"
         const val TYPE_PUKE = "PUKE"
         const val TYPE_BATH = "BATH"
+        const val TYPE_SLEEP = "SLEEP"
     }
 
     private val jo: JSONObject
@@ -100,6 +101,7 @@ class LunaEvent: Comparable<LunaEvent> {
                 TYPE_FOOD -> R.string.event_food_type
                 TYPE_PUKE -> R.string.event_puke_type
                 TYPE_BATH -> R.string.event_bath_type
+                TYPE_SLEEP -> R.string.event_sleep_type
                 else -> R.string.event_unknown_type
             }
         )
@@ -123,6 +125,7 @@ class LunaEvent: Comparable<LunaEvent> {
                 TYPE_FOOD -> R.string.event_food_desc
                 TYPE_PUKE -> R.string.event_puke_desc
                 TYPE_BATH -> R.string.event_bath_desc
+                TYPE_SLEEP -> R.string.event_sleep_desc
                 else -> R.string.event_unknown_desc
             }
         )

app/src/main/java/it/danieleverducci/lunatracker/fragments/DailySummaryFragment.kt

@@ -0,0 +1,123 @@
+package it.danieleverducci.lunatracker.fragments
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.LinearLayout
+import android.widget.ProgressBar
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import it.danieleverducci.lunatracker.R
+import it.danieleverducci.lunatracker.StatisticsActivity
+import utils.DailySummary
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+class DailySummaryFragment : Fragment() {
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.fragment_daily_summary, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        updateUI(view)
+    }
+
+    private fun updateUI(view: View) {
+        val activity = activity as? StatisticsActivity ?: return
+        val calculator = activity.getCalculator()
+        val period = activity.getSelectedPeriod()
+
+        // Get today's summary and average for comparison
+        val todaySummary = calculator.getTodaySummary()
+        val feedingStats = calculator.getFeedingStats(period)
+        val sleepStats = calculator.getSleepStats(period)
+        val diaperStats = calculator.getDiaperStats(period)
+
+        // Date header
+        val dateFormat = SimpleDateFormat("EEEE, d MMMM", Locale.getDefault())
+        view.findViewById<TextView>(R.id.date_header).text = dateFormat.format(Date())
+
+        // Bottle summary
+        val bottleSummary = view.findViewById<TextView>(R.id.bottle_summary)
+        val bottleProgress = view.findViewById<ProgressBar>(R.id.bottle_progress)
+        val avgBottle = feedingStats.avgBottleMlPerDay.toInt()
+        bottleSummary.text = "${todaySummary.totalBottleMl} ml (${todaySummary.bottleCount}×) | Ø $avgBottle ml"
+        if (avgBottle > 0) {
+            bottleProgress.max = (avgBottle * 1.5).toInt()
+            bottleProgress.progress = todaySummary.totalBottleMl
+        }
+
+        // Breastfeeding summary
+        val breastfeedingContainer = view.findViewById<LinearLayout>(R.id.breastfeeding_container)
+        val breastfeedingSummary = view.findViewById<TextView>(R.id.breastfeeding_summary)
+        val breastfeedingProgress = view.findViewById<ProgressBar>(R.id.breastfeeding_progress)
+
+        if (todaySummary.breastfeedingCount > 0 || feedingStats.avgBreastfeedingMinPerDay > 0) {
+            breastfeedingContainer.visibility = View.VISIBLE
+            val avgBf = feedingStats.avgBreastfeedingMinPerDay.toInt()
+            breastfeedingSummary.text = "${todaySummary.totalBreastfeedingMin} min (${todaySummary.breastfeedingCount}×) | Ø $avgBf min"
+            if (avgBf > 0) {
+                breastfeedingProgress.max = (avgBf * 1.5).toInt()
+                breastfeedingProgress.progress = todaySummary.totalBreastfeedingMin
+            }
+        } else {
+            breastfeedingContainer.visibility = View.GONE
+        }
+
+        // Sleep summary
+        val sleepSummary = view.findViewById<TextView>(R.id.sleep_summary)
+        val sleepProgress = view.findViewById<ProgressBar>(R.id.sleep_progress)
+        val avgSleepMin = sleepStats.avgSleepMinPerDay.toInt()
+        val todaySleepHours = todaySummary.totalSleepMin / 60f
+        val avgSleepHours = avgSleepMin / 60f
+        sleepSummary.text = String.format(Locale.getDefault(), "%.1f h (%d×) | Ø %.1f h",
+            todaySleepHours, todaySummary.sleepCount, avgSleepHours)
+        if (avgSleepMin > 0) {
+            sleepProgress.max = (avgSleepMin * 1.5).toInt()
+            sleepProgress.progress = todaySummary.totalSleepMin
+        }
+
+        // Diaper summaries
+        val pooSummary = view.findViewById<TextView>(R.id.poo_summary)
+        val peeSummary = view.findViewById<TextView>(R.id.pee_summary)
+        pooSummary.text = String.format(Locale.getDefault(), "%d× | Ø %.1f",
+            todaySummary.diaperPooCount, diaperStats.avgPooPerDay)
+        peeSummary.text = String.format(Locale.getDefault(), "%d× | Ø %.1f",
+            todaySummary.diaperPeeCount, diaperStats.avgPeePerDay)
+
+        // Health card (weight/temperature)
+        val healthCard = view.findViewById<LinearLayout>(R.id.health_card)
+        val weightSummary = view.findViewById<TextView>(R.id.weight_summary)
+        val tempSummary = view.findViewById<TextView>(R.id.temperature_summary)
+
+        if (todaySummary.latestWeight != null || todaySummary.latestTemperature != null) {
+            healthCard.visibility = View.VISIBLE
+
+            if (todaySummary.latestWeight != null) {
+                val weightKg = todaySummary.latestWeight / 1000f
+                weightSummary.text = "⚖️ ${String.format(Locale.getDefault(), "%.2f kg", weightKg)}"
+                weightSummary.visibility = View.VISIBLE
+            } else {
+                weightSummary.visibility = View.GONE
+            }
+
+            if (todaySummary.latestTemperature != null) {
+                val tempC = todaySummary.latestTemperature / 10f
+                tempSummary.text = "🌡️ ${String.format(Locale.getDefault(), "%.1f °C", tempC)}"
+                tempSummary.visibility = View.VISIBLE
+            } else {
+                tempSummary.visibility = View.GONE
+            }
+        } else {
+            healthCard.visibility = View.GONE
+        }
+    }
+}

app/src/main/java/it/danieleverducci/lunatracker/fragments/DiaperStatsFragment.kt

@@ -0,0 +1,124 @@
+package it.danieleverducci.lunatracker.fragments
+
+import android.os.Bundle
+import android.view.Gravity
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.LinearLayout
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import it.danieleverducci.lunatracker.R
+import it.danieleverducci.lunatracker.StatisticsActivity
+import utils.DateUtils
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+class DiaperStatsFragment : Fragment() {
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.fragment_diaper_stats, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        updateUI(view)
+    }
+
+    private fun updateUI(view: View) {
+        val activity = activity as? StatisticsActivity ?: return
+        val calculator = activity.getCalculator()
+        val period = activity.getSelectedPeriod()
+
+        val stats = calculator.getDiaperStats(period)
+
+        // Draw stacked bar chart
+        val chartContainer = view.findViewById<LinearLayout>(R.id.chart_container)
+        val chartLabels = view.findViewById<LinearLayout>(R.id.chart_labels)
+        chartContainer.removeAllViews()
+        chartLabels.removeAllViews()
+
+        val sortedDays = stats.dailyPooCount.keys.sorted().takeLast(period)
+        var maxValue = 1
+        for (day in sortedDays) {
+            val total = (stats.dailyPooCount[day] ?: 0) + (stats.dailyPeeCount[day] ?: 0)
+            if (total > maxValue) maxValue = total
+        }
+
+        val dateFormat = SimpleDateFormat("E", Locale.getDefault())
+
+        for (day in sortedDays) {
+            val pooCount = stats.dailyPooCount[day] ?: 0
+            val peeCount = stats.dailyPeeCount[day] ?: 0
+            val total = pooCount + peeCount
+
+            // Bar container
+            val barContainer = LinearLayout(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.MATCH_PARENT, 1f)
+                orientation = LinearLayout.VERTICAL
+                gravity = Gravity.BOTTOM or Gravity.CENTER_HORIZONTAL
+                setPadding(4, 0, 4, 0)
+            }
+
+            // Pee bar (lighter, on bottom)
+            if (peeCount > 0) {
+                val peeHeight = (peeCount.toFloat() / maxValue * 100).toInt()
+                val peeBar = View(requireContext()).apply {
+                    layoutParams = LinearLayout.LayoutParams(
+                        LinearLayout.LayoutParams.MATCH_PARENT,
+                        (peeHeight * resources.displayMetrics.density).toInt()
+                    )
+                    setBackgroundColor(0x66FFE68F.toInt()) // Semi-transparent accent
+                }
+                barContainer.addView(peeBar, 0)
+            }
+
+            // Poo bar (solid, on top)
+            if (pooCount > 0) {
+                val pooHeight = (pooCount.toFloat() / maxValue * 100).toInt()
+                val pooBar = View(requireContext()).apply {
+                    layoutParams = LinearLayout.LayoutParams(
+                        LinearLayout.LayoutParams.MATCH_PARENT,
+                        (pooHeight * resources.displayMetrics.density).toInt()
+                    )
+                    setBackgroundColor(resources.getColor(R.color.accent, null))
+                }
+                barContainer.addView(pooBar, 0)
+            }
+
+            chartContainer.addView(barContainer)
+
+            // Label
+            val label = TextView(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f)
+                text = dateFormat.format(Date(day * 1000))
+                textSize = 10f
+                gravity = Gravity.CENTER
+            }
+            chartLabels.addView(label)
+        }
+
+        // Summary stats
+        view.findViewById<TextView>(R.id.avg_diapers).text =
+            getString(R.string.stats_avg_diapers, stats.avgDiapersPerDay)
+        view.findViewById<TextView>(R.id.avg_poo).text =
+            getString(R.string.stats_avg_poo, stats.avgPooPerDay)
+        view.findViewById<TextView>(R.id.avg_pee).text =
+            getString(R.string.stats_avg_pee, stats.avgPeePerDay)
+
+        // Last poo
+        val lastPoo = view.findViewById<TextView>(R.id.last_poo)
+        if (stats.lastPooTime != null) {
+            val timeAgo = DateUtils.formatTimeAgo(requireContext(), stats.lastPooTime)
+            lastPoo.text = getString(R.string.stats_last_poo, timeAgo)
+            lastPoo.visibility = View.VISIBLE
+        } else {
+            lastPoo.visibility = View.GONE
+        }
+    }
+}

app/src/main/java/it/danieleverducci/lunatracker/fragments/FeedingStatsFragment.kt

@@ -0,0 +1,123 @@
+package it.danieleverducci.lunatracker.fragments
+
+import android.os.Bundle
+import android.view.Gravity
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.LinearLayout
+import android.widget.ProgressBar
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import it.danieleverducci.lunatracker.R
+import it.danieleverducci.lunatracker.StatisticsActivity
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+class FeedingStatsFragment : Fragment() {
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.fragment_feeding_stats, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        updateUI(view)
+    }
+
+    private fun updateUI(view: View) {
+        val activity = activity as? StatisticsActivity ?: return
+        val calculator = activity.getCalculator()
+        val period = activity.getSelectedPeriod()
+
+        val stats = calculator.getFeedingStats(period)
+
+        // Draw bar chart
+        val chartContainer = view.findViewById<LinearLayout>(R.id.chart_container)
+        val chartLabels = view.findViewById<LinearLayout>(R.id.chart_labels)
+        chartContainer.removeAllViews()
+        chartLabels.removeAllViews()
+
+        val sortedDays = stats.dailyBottleTotals.keys.sorted().takeLast(period)
+        val maxValue = (stats.dailyBottleTotals.values.maxOrNull() ?: 1).coerceAtLeast(1)
+        val dateFormat = SimpleDateFormat("E", Locale.getDefault())
+
+        for (day in sortedDays) {
+            val value = stats.dailyBottleTotals[day] ?: 0
+
+            // Bar
+            val barContainer = LinearLayout(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.MATCH_PARENT, 1f)
+                orientation = LinearLayout.VERTICAL
+                gravity = Gravity.BOTTOM or Gravity.CENTER_HORIZONTAL
+                setPadding(4, 0, 4, 0)
+            }
+
+            val barHeight = if (maxValue > 0) (value.toFloat() / maxValue * 100).toInt() else 0
+            val bar = View(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(
+                    LinearLayout.LayoutParams.MATCH_PARENT,
+                    0
+                ).apply {
+                    height = (barHeight * resources.displayMetrics.density).toInt()
+                }
+                setBackgroundColor(resources.getColor(R.color.accent, null))
+            }
+            barContainer.addView(bar)
+            chartContainer.addView(barContainer)
+
+            // Label
+            val label = TextView(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f)
+                text = dateFormat.format(Date(day * 1000))
+                textSize = 10f
+                gravity = Gravity.CENTER
+            }
+            chartLabels.addView(label)
+        }
+
+        // Bottle stats
+        val bottleAvg = view.findViewById<TextView>(R.id.bottle_avg_daily)
+        bottleAvg.text = getString(R.string.stats_avg_ml_per_day, stats.avgBottleMlPerDay)
+
+        val feedingInterval = view.findViewById<TextView>(R.id.feeding_interval)
+        feedingInterval.text = getString(R.string.stats_feeding_interval, stats.avgFeedingIntervalMinutes.toInt())
+
+        // Breastfeeding stats
+        val breastfeedingCard = view.findViewById<LinearLayout>(R.id.breastfeeding_card)
+        val totalBreastfeeding = stats.leftBreastCount + stats.rightBreastCount + stats.bothBreastCount
+
+        if (totalBreastfeeding > 0) {
+            breastfeedingCard.visibility = View.VISIBLE
+
+            val avgDuration = view.findViewById<TextView>(R.id.breastfeeding_avg_duration)
+            avgDuration.text = getString(R.string.stats_avg_duration, stats.avgBreastfeedingDuration)
+
+            // Side distribution (excluding "both")
+            val sideTotal = stats.leftBreastCount + stats.rightBreastCount
+            if (sideTotal > 0) {
+                val leftPercent = (stats.leftBreastCount.toFloat() / sideTotal * 100).toInt()
+                val rightPercent = (stats.rightBreastCount.toFloat() / sideTotal * 100).toInt()
+
+                val leftProgress = view.findViewById<ProgressBar>(R.id.left_progress)
+                val rightProgress = view.findViewById<ProgressBar>(R.id.right_progress)
+                val leftPercentText = view.findViewById<TextView>(R.id.left_percent)
+                val rightPercentText = view.findViewById<TextView>(R.id.right_percent)
+
+                leftProgress.max = 100
+                leftProgress.progress = leftPercent
+                rightProgress.max = 100
+                rightProgress.progress = rightPercent
+                leftPercentText.text = "$leftPercent%"
+                rightPercentText.text = "$rightPercent%"
+            }
+        } else {
+            breastfeedingCard.visibility = View.GONE
+        }
+    }
+}

app/src/main/java/it/danieleverducci/lunatracker/fragments/GrowthStatsFragment.kt

@@ -0,0 +1,139 @@
+package it.danieleverducci.lunatracker.fragments
+
+import android.os.Bundle
+import android.view.Gravity
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.LinearLayout
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import it.danieleverducci.lunatracker.R
+import it.danieleverducci.lunatracker.StatisticsActivity
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+class GrowthStatsFragment : Fragment() {
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.fragment_growth_stats, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        updateUI(view)
+    }
+
+    private fun updateUI(view: View) {
+        val activity = activity as? StatisticsActivity ?: return
+        val calculator = activity.getCalculator()
+
+        val weightHistory = calculator.getWeightHistory()
+        val noDataMessage = view.findViewById<TextView>(R.id.no_data_message)
+
+        if (weightHistory.isEmpty()) {
+            noDataMessage.visibility = View.VISIBLE
+            view.findViewById<View>(R.id.chart_container).visibility = View.GONE
+            view.findViewById<View>(R.id.chart_labels).visibility = View.GONE
+            view.findViewById<TextView>(R.id.current_weight).visibility = View.GONE
+            view.findViewById<TextView>(R.id.weight_gain_week).visibility = View.GONE
+            view.findViewById<TextView>(R.id.weight_gain_month).visibility = View.GONE
+            return
+        }
+
+        noDataMessage.visibility = View.GONE
+
+        // Draw weight chart (line chart approximated with bars)
+        val chartContainer = view.findViewById<LinearLayout>(R.id.chart_container)
+        val chartLabels = view.findViewById<LinearLayout>(R.id.chart_labels)
+        chartContainer.removeAllViews()
+        chartLabels.removeAllViews()
+
+        val recentWeights = weightHistory.takeLast(10) // Show last 10 measurements
+        val minWeight = recentWeights.minOfOrNull { it.weightGrams } ?: 0
+        val maxWeight = recentWeights.maxOfOrNull { it.weightGrams } ?: 1
+        val weightRange = (maxWeight - minWeight).coerceAtLeast(100) // At least 100g range
+        val dateFormat = SimpleDateFormat("d/M", Locale.getDefault())
+
+        for (point in recentWeights) {
+            // Bar container
+            val barContainer = LinearLayout(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.MATCH_PARENT, 1f)
+                orientation = LinearLayout.VERTICAL
+                gravity = Gravity.BOTTOM or Gravity.CENTER_HORIZONTAL
+                setPadding(4, 0, 4, 0)
+            }
+
+            // Calculate relative height (showing weight above minimum)
+            val relativeWeight = point.weightGrams - minWeight + (weightRange * 0.1).toInt()
+            val barHeight = (relativeWeight.toFloat() / (weightRange * 1.2) * 100).toInt()
+
+            val bar = View(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(
+                    LinearLayout.LayoutParams.MATCH_PARENT,
+                    (barHeight * resources.displayMetrics.density).toInt()
+                )
+                setBackgroundColor(resources.getColor(R.color.accent, null))
+            }
+            barContainer.addView(bar)
+
+            // Weight value on top
+            val weightLabel = TextView(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(
+                    LinearLayout.LayoutParams.WRAP_CONTENT,
+                    LinearLayout.LayoutParams.WRAP_CONTENT
+                )
+                val kg = point.weightGrams / 1000f
+                text = String.format(Locale.getDefault(), "%.1f", kg)
+                textSize = 8f
+                gravity = Gravity.CENTER
+            }
+            barContainer.addView(weightLabel, 0)
+
+            chartContainer.addView(barContainer)
+
+            // Date label
+            val label = TextView(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f)
+                text = dateFormat.format(Date(point.time * 1000))
+                textSize = 10f
+                gravity = Gravity.CENTER
+            }
+            chartLabels.addView(label)
+        }
+
+        // Current weight
+        val currentWeight = weightHistory.lastOrNull()
+        if (currentWeight != null) {
+            val kg = currentWeight.weightGrams / 1000f
+            view.findViewById<TextView>(R.id.current_weight).text =
+                getString(R.string.stats_current_weight, String.format(Locale.getDefault(), "%.2f kg", kg))
+        }
+
+        // Weight gain calculations
+        val gainWeek = calculator.getWeightGainForDays(7)
+        val gainMonth = calculator.getWeightGainForDays(30)
+
+        val weekView = view.findViewById<TextView>(R.id.weight_gain_week)
+        val monthView = view.findViewById<TextView>(R.id.weight_gain_month)
+
+        if (gainWeek != null) {
+            weekView.text = getString(R.string.stats_weight_gain_week, gainWeek)
+            weekView.visibility = View.VISIBLE
+        } else {
+            weekView.visibility = View.GONE
+        }
+
+        if (gainMonth != null) {
+            monthView.text = getString(R.string.stats_weight_gain_month, gainMonth)
+            monthView.visibility = View.VISIBLE
+        } else {
+            monthView.visibility = View.GONE
+        }
+    }
+}

app/src/main/java/it/danieleverducci/lunatracker/fragments/SleepStatsFragment.kt

@@ -0,0 +1,105 @@
+package it.danieleverducci.lunatracker.fragments
+
+import android.os.Bundle
+import android.view.Gravity
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.LinearLayout
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import it.danieleverducci.lunatracker.R
+import it.danieleverducci.lunatracker.StatisticsActivity
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+class SleepStatsFragment : Fragment() {
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.fragment_sleep_stats, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        super.onViewCreated(view, savedInstanceState)
+        updateUI(view)
+    }
+
+    private fun updateUI(view: View) {
+        val activity = activity as? StatisticsActivity ?: return
+        val calculator = activity.getCalculator()
+        val period = activity.getSelectedPeriod()
+
+        val stats = calculator.getSleepStats(period)
+
+        // Check if we have any sleep data
+        val hasSleepData = stats.dailyTotals.values.any { it > 0 }
+        val noDataMessage = view.findViewById<TextView>(R.id.no_data_message)
+
+        if (!hasSleepData) {
+            noDataMessage.visibility = View.VISIBLE
+            view.findViewById<View>(R.id.chart_container).visibility = View.GONE
+            view.findViewById<View>(R.id.chart_labels).visibility = View.GONE
+            return
+        }
+
+        noDataMessage.visibility = View.GONE
+
+        // Draw bar chart (showing hours per day)
+        val chartContainer = view.findViewById<LinearLayout>(R.id.chart_container)
+        val chartLabels = view.findViewById<LinearLayout>(R.id.chart_labels)
+        chartContainer.removeAllViews()
+        chartLabels.removeAllViews()
+
+        val sortedDays = stats.dailyTotals.keys.sorted().takeLast(period)
+        val maxValue = (stats.dailyTotals.values.maxOrNull() ?: 1).coerceAtLeast(1)
+        val dateFormat = SimpleDateFormat("E", Locale.getDefault())
+
+        for (day in sortedDays) {
+            val minutes = stats.dailyTotals[day] ?: 0
+
+            // Bar container
+            val barContainer = LinearLayout(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.MATCH_PARENT, 1f)
+                orientation = LinearLayout.VERTICAL
+                gravity = Gravity.BOTTOM or Gravity.CENTER_HORIZONTAL
+                setPadding(4, 0, 4, 0)
+            }
+
+            val barHeight = if (maxValue > 0) (minutes.toFloat() / maxValue * 100).toInt() else 0
+            val bar = View(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(
+                    LinearLayout.LayoutParams.MATCH_PARENT,
+                    (barHeight * resources.displayMetrics.density).toInt()
+                )
+                setBackgroundColor(resources.getColor(R.color.accent, null))
+            }
+            barContainer.addView(bar)
+            chartContainer.addView(barContainer)
+
+            // Label
+            val label = TextView(requireContext()).apply {
+                layoutParams = LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f)
+                text = dateFormat.format(Date(day * 1000))
+                textSize = 10f
+                gravity = Gravity.CENTER
+            }
+            chartLabels.addView(label)
+        }
+
+        // Summary stats
+        val avgSleepHours = stats.avgSleepMinPerDay / 60f
+        view.findViewById<TextView>(R.id.avg_sleep_per_day).text =
+            getString(R.string.stats_avg_sleep, avgSleepHours)
+        view.findViewById<TextView>(R.id.avg_naps_per_day).text =
+            getString(R.string.stats_avg_naps, stats.avgNapsPerDay)
+        view.findViewById<TextView>(R.id.avg_nap_duration).text =
+            getString(R.string.stats_avg_nap_duration, stats.avgNapDurationMin)
+        view.findViewById<TextView>(R.id.longest_sleep).text =
+            getString(R.string.stats_longest_sleep, stats.longestSleepMin)
+    }
+}

app/src/main/java/it/danieleverducci/lunatracker/repository/LocalSettingsRepository.kt

@@ -17,6 +17,7 @@ class LocalSettingsRepository(val context: Context) {
         const val SHARED_PREFS_SIGNATURE = "signature"
         const val SHARED_PREFS_BF_TIMER_START = "bf_timer_start"
         const val SHARED_PREFS_BF_TIMER_TYPE = "bf_timer_type"
+        const val SHARED_PREFS_SLEEP_TIMER_START = "sleep_timer_start"
     }
     enum class DATA_REPO {LOCAL_FILE, WEBDAV}
     val sharedPreferences: SharedPreferences
@@ -107,4 +108,20 @@ class LocalSettingsRepository(val context: Context) {
             remove(SHARED_PREFS_BF_TIMER_TYPE)
         }
     }
+
+    fun saveSleepTimer(startTime: Long) {
+        sharedPreferences.edit {
+            putLong(SHARED_PREFS_SLEEP_TIMER_START, startTime)
+        }
+    }
+
+    fun loadSleepTimer(): Long {
+        return sharedPreferences.getLong(SHARED_PREFS_SLEEP_TIMER_START, 0)
+    }
+
+    fun clearSleepTimer() {
+        sharedPreferences.edit {
+            remove(SHARED_PREFS_SLEEP_TIMER_START)
+        }
+    }
 }