feat: Show the calendar for current month

app/build.gradle.kts

@@ -50,4 +50,5 @@ dependencies {
     implementation("com.squareup.retrofit2:retrofit:2.11.0")
     implementation("com.squareup.retrofit2:converter-gson:2.11.0")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.10.1")
+    implementation("com.jakewharton.threetenabp:threetenabp:1.4.4")
 }

app/src/main/java/com/p_vacho/neat_calendar/MyApplication.kt

@@ -4,6 +4,7 @@ import android.app.Application
 import com.p_vacho.neat_calendar.api.RetrofitClient
 import com.p_vacho.neat_calendar.util.auth.AuthRepository
 import com.p_vacho.neat_calendar.util.auth.TokenManager
+import com.jakewharton.threetenabp.AndroidThreeTen
 
 class MyApplication : Application() {
     lateinit var tokenManager: TokenManager
@@ -15,6 +16,9 @@ class MyApplication : Application() {
     override fun onCreate() {
         super.onCreate()
 
+        // Initialize the timezone information
+        AndroidThreeTen.init(this)
+
         // Initialize RetrofitClient (mutating the global object)
         RetrofitClient.initialize(this)
 

app/src/main/java/com/p_vacho/neat_calendar/activities/CalendarActivity.kt

@@ -1,13 +1,27 @@
 package com.p_vacho.neat_calendar.activities
 
 import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.TextView
 import androidx.activity.enableEdgeToEdge
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsCompat
+import androidx.recyclerview.widget.GridLayoutManager
+import androidx.recyclerview.widget.RecyclerView
 import com.p_vacho.neat_calendar.R
+import org.threeten.bp.LocalDate
+import org.threeten.bp.YearMonth
+import org.threeten.bp.format.TextStyle
+import java.time.temporal.WeekFields
+import java.util.Locale
 
 class CalendarActivity : AppCompatActivity() {
+    private lateinit var tvMonthYear: TextView
+    private lateinit var rvCalendar: RecyclerView
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
@@ -18,10 +32,60 @@ class CalendarActivity : AppCompatActivity() {
             insets
         }
 
-        initializeCalendar()
+        tvMonthYear = findViewById(R.id.tvMonthYear)
+        rvCalendar = findViewById(R.id.rvCalendar)
+
+        val currentMonth = YearMonth.now()
+        setCalendarForMonth(currentMonth)
     }
 
-    private fun initializeCalendar() {
-        // TODO("Not yet implemented")
+    private fun setCalendarForMonth(yearMonth: YearMonth) {
+        val firstDayOfMonth = yearMonth.atDay(1)
+        val daysInMonth = yearMonth.lengthOfMonth()
+
+        // Get localized month name and year
+        val monthYearText = "${yearMonth.month.getDisplayName(TextStyle.FULL, Locale.getDefault())} ${yearMonth.year}"
+        tvMonthYear.text = monthYearText
+
+        // Calculate the day of the week the month starts on (Monday as first day)
+        val dayOfWeek = firstDayOfMonth.dayOfWeek.value // 1 (Monday) to 7 (Sunday)
+        val startOffset = (dayOfWeek - 1 + 7) % 7 // Shift Sunday (7) to the correct position for Monday start
+
+        // Generate calendar days
+        val days = mutableListOf<String>()
+
+        // Add padding for days of the previous month
+        for (i in 1..startOffset) {
+            days.add("") // Empty strings represent padding days
+        }
+
+        // Add the actual days of the current month
+        for (i in 1..daysInMonth) {
+            days.add(i.toString())
+        }
+
+        // Set up RecyclerView
+        rvCalendar.layoutManager = GridLayoutManager(this, 7) // 7 columns for days of the week
+        rvCalendar.adapter = CalendarAdapter(days)
     }
-}
+}
+
+class CalendarAdapter(private val days: List<String>) :
+    RecyclerView.Adapter<CalendarAdapter.DayViewHolder>() {
+
+    class DayViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
+        val tvDay: TextView = itemView.findViewById(android.R.id.text1)
+    }
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): DayViewHolder {
+        val view = LayoutInflater.from(parent.context)
+            .inflate(android.R.layout.simple_list_item_1, parent, false)
+        return DayViewHolder(view)
+    }
+
+    override fun onBindViewHolder(holder: DayViewHolder, position: Int) {
+        holder.tvDay.text = days[position]
+    }
+
+    override fun getItemCount(): Int = days.size
+}

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

@@ -8,12 +8,28 @@
     tools:context=".activities.CalendarActivity">
 
     <TextView
-        android:layout_width="wrap_content"
+        android:id="@+id/tvMonthYear"
+        android:layout_width="0dp"
         android:layout_height="wrap_content"
-        android:text="Hello World!"
-        app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
+        android:gravity="center"
+        android:padding="16dp"
+        android:text=""
+        tools:text="January 2024"
+        android:textAppearance="?attr/textAppearanceHeadline6"
+        app:layout_constraintTop_toTopOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent" />
+        app:layout_constraintEnd_toEndOf="parent" />
 
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/rvCalendar"
+        android:layout_width="0dp"
+        android:layout_height="0dp"
+        android:padding="8dp"
+        app:layout_constraintTop_toBottomOf="@id/tvMonthYear"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintBottom_toBottomOf="parent"
+        android:scrollbars="none"
+        tools:listitem="@layout/item_calendar_day"
+        tools:itemCount="6"/>
 </androidx.constraintlayout.widget.ConstraintLayout>

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

@@ -1,6 +1,12 @@
-<?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
-             android:layout_width="match_parent"
-             android:layout_height="match_parent">
-
-</androidx.constraintlayout.widget.ConstraintLayout>
+<TextView
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/tvDay"
+    android:layout_width="40dp"
+    android:layout_height="40dp"
+    android:gravity="center"
+    android:textColor="?attr/colorOnBackground"
+    android:background="?attr/selectableItemBackground"
+    tools:text="1"
+    android:textAppearance="?attr/textAppearanceBody1" />