diff --git a/.idea/deploymentTargetSelector.xml b/.idea/deploymentTargetSelector.xml
index b3bb7eb..8fc3e1a 100644
--- a/.idea/deploymentTargetSelector.xml
+++ b/.idea/deploymentTargetSelector.xml
@@ -4,7 +4,7 @@
     <selectionStates>
       <SelectionState runConfigName="app">
         <option name="selectionMode" value="DROPDOWN" />
-        <DropdownSelection timestamp="2024-09-08T10:52:57.628174800Z">
+        <DropdownSelection timestamp="2024-09-09T18:25:06.130054Z">
           <Target type="DEFAULT_BOOT">
             <handle>
               <DeviceId pluginId="LocalEmulator" identifier="path=C:\Users\StepanovPlaton\.android\avd\Medium_Phone_API_30.avd" />
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..94a25f7
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 50446f4..2f9c5ec 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -3,6 +3,7 @@ import com.android.build.api.variant.BuildConfigField
 plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.android)
+    alias(libs.plugins.kotlin.serialization)
     alias(libs.plugins.compose.compiler)
 }
 
@@ -35,8 +36,21 @@ android {
     androidComponents {
         onVariants {
             it.buildConfigFields.putAll(mapOf(
-                Pair("BASE_URL", BuildConfigField("String", "\"https://lk.ssau.ru/\"", null)),
-                Pair("SIGN_IN_URL", BuildConfigField("String", "\"account/login\"", null))
+                Pair("BASE_URL",
+                    BuildConfigField("String",
+                        "\"https://lk.ssau.ru/\"", null)),
+                Pair("SIGN_IN_URL",
+                    BuildConfigField("String",
+                        "\"account/login\"", null)),
+                Pair("USER_DETAILS_URL",
+                    BuildConfigField("String",
+                        "\"api/proxy/current-user-details\"", null)),
+                Pair("USER_GROUPS_URL",
+                    BuildConfigField("String",
+                        "\"api/proxy/personal/groups\"", null)),
+                Pair("YEARS_URL",
+                    BuildConfigField("String",
+                        "\"api/proxy/dictionaries?slug=unified_years\"", null))
             ))
         }
     }
@@ -62,7 +76,6 @@ android {
 }
 
 dependencies {
-
     implementation(libs.androidx.core.ktx)
     implementation(libs.androidx.lifecycle.runtime.ktx)
     implementation(libs.androidx.activity.compose)
@@ -82,4 +95,5 @@ dependencies {
 
     implementation(libs.squareup.okhttp)
     implementation(libs.androidx.datastore)
+    implementation(libs.kotlinx.serialization.json)
 }
\ No newline at end of file
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 228170f..d78e111 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -25,5 +25,11 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:theme="@style/Theme.SSAU_Schedule"
+            android:screenOrientation="portrait">
+        </activity>
     </application>
 </manifest>
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/AuthActivity.kt b/app/src/main/java/com/example/ssau_schedule/AuthActivity.kt
index acc7055..1751a0e 100644
--- a/app/src/main/java/com/example/ssau_schedule/AuthActivity.kt
+++ b/app/src/main/java/com/example/ssau_schedule/AuthActivity.kt
@@ -1,5 +1,6 @@
 package com.example.ssau_schedule
 
+import android.annotation.SuppressLint
 import android.content.Intent
 import android.os.Bundle
 import androidx.activity.ComponentActivity
@@ -8,10 +9,9 @@ import androidx.activity.enableEdgeToEdge
 import androidx.compose.animation.AnimatedVisibility
 import androidx.compose.animation.animateContentSize
 import androidx.compose.animation.core.Spring
+import androidx.compose.animation.core.animateDpAsState
 import androidx.compose.animation.core.animateFloatAsState
 import androidx.compose.animation.core.spring
-import androidx.compose.animation.fadeIn
-import androidx.compose.animation.fadeOut
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.background
 import androidx.compose.foundation.layout.Box
@@ -32,40 +32,58 @@ import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.FilledTonalButton
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Snackbar
+import androidx.compose.material3.SnackbarHost
+import androidx.compose.material3.SnackbarHostState
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.remember
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.layout.ContentScale
-import androidx.compose.ui.res.painterResource
-import com.example.ssau_schedule.ui.theme.SSAU_ScheduleTheme
-import kotlinx.coroutines.delay
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.BiasAlignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.shadow
+import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.platform.LocalConfiguration
+import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
 import androidx.core.view.WindowCompat
+import com.example.ssau_schedule.api.ApiErrorMessage
 import com.example.ssau_schedule.api.AuthErrorMessage
 import com.example.ssau_schedule.api.AuthorizationAPI
 import com.example.ssau_schedule.api.Http
+import com.example.ssau_schedule.api.GeneralApi
+import com.example.ssau_schedule.data.store.AuthStore
+import com.example.ssau_schedule.data.store.GeneralStore
+import com.example.ssau_schedule.data.store.Group
+import com.example.ssau_schedule.data.store.User
+import com.example.ssau_schedule.data.store.Year
+import com.example.ssau_schedule.ui.theme.ApplicationColors
+import com.example.ssau_schedule.ui.theme.SSAU_ScheduleTheme
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import java.text.SimpleDateFormat
+import java.util.Calendar
+import java.util.Date
 import kotlin.math.min
 
 class AuthActivity : ComponentActivity() {
+
     private val http = Http()
-    private var auth: AuthorizationAPI? = null
+    private var authApi: AuthorizationAPI? = null
+    private var userApi: GeneralApi? = null
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         enableEdgeToEdge()
 
-        auth = AuthorizationAPI.getInstance(http, applicationContext)
         WindowCompat.setDecorFitsSystemWindows(window, false)
 
         setContent {
@@ -77,128 +95,255 @@ class AuthActivity : ComponentActivity() {
 
     @Composable
     fun AuthPage() {
-        var loginOpen by remember { mutableStateOf(false) }
+        val authScope = rememberCoroutineScope()
+        authApi = remember { AuthorizationAPI(http, applicationContext, authScope) }
+        userApi = remember { GeneralApi(http, applicationContext, authScope) }
+
+        var user by remember { mutableStateOf<User?>(null) }
+        var group by remember { mutableStateOf<Group?>(null) }
+        var year by remember { mutableStateOf<Year?>(null) }
+
+
+        var needAuth by remember { mutableStateOf(false) }
+        var entered by remember { mutableStateOf(false) }
+
         val keyboardOpen by Utils.keyboardState()
+        val snackbarHostState = remember { SnackbarHostState() }
         val logoHeight by animateFloatAsState(
-            if (keyboardOpen) 0f else min(LocalConfiguration.current.screenWidthDp, 500) / 101f * 48f,
+            if (keyboardOpen) 0f else min(
+                LocalConfiguration.current.screenWidthDp,
+                500
+            ) / 101f * 48f,
             label = "alpha",
             animationSpec = spring(
                 dampingRatio = Spring.DampingRatioMediumBouncy,
                 stiffness = Spring.StiffnessLow
-            ))
+            )
+        )
 
-
-        LaunchedEffect(false) {
-            delay(1000)
-            loginOpen = true
+        LaunchedEffect(user, group, year) {
+            if(user != null && group != null && year != null) {
+                delay(1500)
+                startActivity(Intent(applicationContext, MainActivity::class.java))
+            }
         }
 
-        Box(Modifier.background(MaterialTheme.colorScheme.primary)
-                .fillMaxSize().statusBarsPadding().navigationBarsPadding().imePadding(),
-            contentAlignment = BiasAlignment(0f, -0.25f),
-        ) {
-
-            Column(horizontalAlignment = Alignment.CenterHorizontally) {
-                Box(Modifier.widthIn(0.dp, 500.dp)
-                    .height(logoHeight.dp).padding(20.dp, 0.dp)
-                ) {
-                    Image(painterResource(R.drawable.ssau_logo_01),
-                        contentDescription = stringResource(R.string.samara_university),
-                        modifier = Modifier.fillMaxSize().padding(10.dp),
-                        contentScale = ContentScale.FillWidth,
-                        alignment = Alignment.TopCenter)
+        LaunchedEffect(entered) {
+            delay(1000)
+            AuthStore.getAuthToken(applicationContext, authScope) { authToken ->
+                if(authToken != null) {
+                    userApi?.getUserDetails(authToken, { u -> user = u }, { needAuth = true })
+                    userApi?.getUserGroups(authToken,
+                        { groups ->
+                            GeneralStore.getCurrentGroup(applicationContext, authScope) { g ->
+                                if(g != null && groups.contains(g)) group = g
+                                else  {
+                                    GeneralStore.setCurrentGroup(groups[0],
+                                        applicationContext, authScope)
+                                    group = groups[0]
+                                }
+                            }
+                        }, { error ->
+                            if(error != ApiErrorMessage.USER_NOT_AUTHORIZED) {
+                                authScope.launch {
+                                    val message = error.getMessage(applicationContext)
+                                    if(message != null) snackbarHostState.showSnackbar(message)
+                                }
+                            } else needAuth = true
+                        })
+                    GeneralStore.getCurrentYear(applicationContext, authScope) { y ->
+                        if(y != null && y.hasDate(Date())) year = y
+                        else  {
+                            userApi?.getYears(authToken,
+                                { rawYears ->
+                                    val currentRawYear = rawYears.find { y -> y.isCurrent }
+                                    if(currentRawYear != null) {
+                                        year = currentRawYear.toYear()
+                                        GeneralStore.setCurrentYear(year!!,
+                                            applicationContext, authScope)
+                                    } else {
+                                        authScope.launch {
+                                            val message = ApiErrorMessage.FAILED_GET_YEARS
+                                                .getMessage(applicationContext)
+                                            if(message != null)
+                                                snackbarHostState.showSnackbar(message)
+                                        }
+                                    }
+                                }, { error ->
+                                    if(error != ApiErrorMessage.USER_NOT_AUTHORIZED) {
+                                        authScope.launch {
+                                            val message = error.getMessage(applicationContext)
+                                            if(message != null)
+                                                snackbarHostState.showSnackbar(message)
+                                        }
+                                    } else needAuth = true
+                                })
+                        }
+                    }
                 }
-                Box(Modifier.padding(20.dp, 0.dp).widthIn(0.dp, 400.dp)) {
-                    Card(Modifier.fillMaxWidth().animateContentSize(animationSpec = spring(
-                        dampingRatio = Spring.DampingRatioLowBouncy,
-                        stiffness = 50f
-                        ))
-                        .height(if(loginOpen) 280.dp else 0.dp),
-                        colors = CardDefaults.cardColors(
-                            containerColor = MaterialTheme.colorScheme.background,
-                        ),
-                        elevation = CardDefaults.cardElevation(defaultElevation = 10.dp)
-                    ) {
-                        AuthForm()
+                else needAuth = true
+            }
+        }
+
+        Scaffold(
+            snackbarHost = {
+                SnackbarHost(hostState = snackbarHostState) {
+                    Snackbar(
+                        snackbarData = it,
+                        containerColor = MaterialTheme.colorScheme.errorContainer,
+                    )
+                }
+            }
+        ) { padding ->
+            Box(
+                Modifier
+                    .background(MaterialTheme.colorScheme.primary)
+                    .fillMaxSize()
+                    .padding(padding)
+                    .statusBarsPadding()
+                    .navigationBarsPadding()
+                    .imePadding(),
+                contentAlignment = BiasAlignment(0f, -0.25f),
+            ) {
+                Column(horizontalAlignment = Alignment.CenterHorizontally) {
+                    Box(
+                        Modifier
+                            .widthIn(0.dp, 500.dp)
+                            .height(logoHeight.dp)
+                            .padding(20.dp, 0.dp)) {
+                        Image(painterResource(R.drawable.ssau_logo_01),
+                            contentDescription = stringResource(R.string.samara_university),
+                            modifier = Modifier
+                                .fillMaxSize()
+                                .padding(10.dp),
+                            contentScale = ContentScale.FillWidth,
+                            alignment = Alignment.TopCenter)
+                    }
+                    Box(
+                        Modifier
+                            .padding(20.dp, 0.dp)
+                            .widthIn(0.dp, 400.dp)) {
+                        Column {
+                            WelcomeMessage(user, group, year)
+                            AuthForm(open = needAuth) {
+                                needAuth = false
+                                entered = true
+                            }
+                        }
+
                     }
                 }
             }
         }
+
     }
 
     @Composable
-    fun AuthForm() {
-        val authScope = rememberCoroutineScope()
+    fun AuthForm(open: Boolean, callback: () -> Unit) {
         var login by remember { mutableStateOf("") }
         var password by remember { mutableStateOf("") }
         var error by remember { mutableStateOf<AuthErrorMessage?>(null) }
 
-        Column(Modifier.fillMaxWidth().padding(30.dp, 20.dp),
-            horizontalAlignment = Alignment.CenterHorizontally
+        val height by animateDpAsState(if (open) 290.dp else 0.dp, label = "Auth form height",
+            animationSpec = spring(
+                dampingRatio = Spring.DampingRatioLowBouncy,
+                stiffness = Spring.StiffnessLow
+            )
+        )
+
+        Card(
+            Modifier
+                .fillMaxWidth()
+                .height(height)
+                .padding(0.dp, 10.dp)
+                .shadow(10.dp),
+            colors = CardDefaults.cardColors(
+                containerColor = MaterialTheme.colorScheme.background,
+            ),
         ) {
-            Text(
-                stringResource(R.string.sign_in),
-                modifier = Modifier.fillMaxWidth(),
-                color = MaterialTheme.colorScheme.primary,
-                textAlign = TextAlign.Center,
-                style = MaterialTheme.typography.displaySmall
-            )
-            OutlinedTextField(
-                modifier = Modifier.fillMaxWidth(),
-                value = login,
-                onValueChange = { login = it; error = null },
-                label = { Text(stringResource(R.string.login)) },
-                placeholder =
-                { Text(stringResource(R.string.enter_your_login)) },
-            )
-            Spacer(Modifier.height(2.dp))
-            OutlinedTextField(
-                modifier = Modifier.fillMaxWidth(),
-                value = password,
-                onValueChange = { password = it; error = null },
-                label = { Text(stringResource(R.string.password)) },
-                placeholder =
-                { Text(stringResource(R.string.enter_your_password)) },
-            )
-            Spacer(Modifier.height(2.dp))
-            Box(Modifier.fillMaxWidth().height(14.dp)) {
-                this@Column.AnimatedVisibility(
-                    modifier = Modifier.align(Alignment.Center),
-                    visible = error !== null,
-                    enter = fadeIn(animationSpec = spring(
-                        dampingRatio = Spring.DampingRatioMediumBouncy,
-                        stiffness = Spring.StiffnessVeryLow
-                    )),
-                    exit = fadeOut(animationSpec = spring(
-                        dampingRatio = Spring.DampingRatioMediumBouncy,
-                        stiffness = Spring.StiffnessVeryLow
-                    ))
-                ) {
-                    Text(error?.getMessage(applicationContext) ?: "",
-                        color = MaterialTheme.colorScheme.error,
-                        style = MaterialTheme.typography.labelSmall
+            Column(
+                Modifier
+                    .fillMaxWidth()
+                    .padding(30.dp, 20.dp),
+                horizontalAlignment = Alignment.CenterHorizontally
+            ) {
+                Text(stringResource(R.string.sign_in),
+                    modifier = Modifier.fillMaxWidth(),
+                    color = MaterialTheme.colorScheme.primary,
+                    textAlign = TextAlign.Center,
+                    style = MaterialTheme.typography.displaySmall)
+                OutlinedTextField(modifier = Modifier.fillMaxWidth(),
+                    value = login,
+                    onValueChange = { login = it; error = null },
+                    label = { Text(stringResource(R.string.login)) },
+                    placeholder = { Text(stringResource(R.string.enter_your_login)) })
+                Spacer(Modifier.height(2.dp))
+                OutlinedTextField(modifier = Modifier.fillMaxWidth(),
+                    value = password,
+                    onValueChange = { password = it; error = null },
+                    label = { Text(stringResource(R.string.password)) },
+                    placeholder = { Text(stringResource(R.string.enter_your_password)) })
+                Spacer(Modifier.height(2.dp))
+                Box(
+                    Modifier
+                        .fillMaxWidth()
+                        .height(14.dp)) {
+                    this@Column.AnimatedVisibility(
+                        modifier = Modifier.align(Alignment.Center),
+                        visible = error !== null
+                    ) {
+                        Text(error?.getMessage(applicationContext) ?: "",
+                            color = MaterialTheme.colorScheme.error,
+                            style = MaterialTheme.typography.labelSmall)
+                    }
+                }
+                Spacer(Modifier.height(4.dp))
+                FilledTonalButton(
+                    onClick = {
+                        if (login.length < 5)
+                            error = AuthErrorMessage.LOGIN_IS_TOO_SHORT
+                        else if (password.length < 5)
+                            error = AuthErrorMessage.PASSWORD_IS_TOO_SHORT
+                        else {
+                            authApi?.signIn(login, password,
+                                { callback() },
+                                { error = AuthErrorMessage.INCORRECT_LOGIN_OR_PASSWORD }
+                            )
+                        }
+                    },
+                    shape = RoundedCornerShape(50),
+                    colors = ButtonDefaults.buttonColors(
+                        containerColor = MaterialTheme.colorScheme.primary
                     )
+                ) {
+                    Text(stringResource(R.string.sign_in))
                 }
             }
+        }
+    }
 
-            Spacer(Modifier.height(4.dp))
-            FilledTonalButton(onClick = {
-                if(login.length < 5) error = AuthErrorMessage.LOGIN_IS_TOO_SHORT
-                else if(password.length < 5) error = AuthErrorMessage.PASSWORD_IS_TOO_SHORT
-                else {
-                    auth?.signIn(login, password, authScope,
-                        { startActivity(Intent(applicationContext, AuthActivity::class.java)) },
-                        { _, _ ->
-                            error = AuthErrorMessage.INCORRECT_LOGIN_OR_PASSWORD
-                        }
-                    )
-                }
-            },
-                shape = RoundedCornerShape(50),
-                colors = ButtonDefaults.buttonColors(
-                    containerColor = MaterialTheme.colorScheme.primary)
-            ) {
-                Text(stringResource(R.string.sign_in))
+    @SuppressLint("SimpleDateFormat")
+    @Composable
+    fun WelcomeMessage(user: User?, group: Group?, year: Year?) {
+        val currentDate =  remember { SimpleDateFormat("d MMMM").format(Date()) }
+        val currentYear = remember { Calendar.getInstance().get(Calendar.YEAR); }
+        Column(Modifier.fillMaxWidth().animateContentSize(),
+            horizontalAlignment = Alignment.CenterHorizontally
+        ) {
+            if(user !== null && group != null && year != null) {
+                Text("Здравствуйте ${user.name}!",
+                    color = ApplicationColors.White,
+                    style = MaterialTheme.typography.headlineSmall,
+                    textAlign = TextAlign.Center)
+                Text("Расписание для группы ${group.name}",
+                    color = ApplicationColors.White,
+                    style = MaterialTheme.typography.titleSmall,
+                    textAlign = TextAlign.Center)
+                Text("$currentDate, ${year.getWeekOfDate(Date())} "+
+                        "учебная неделя, ${currentYear}-${currentYear+1} учебный год",
+                    color = ApplicationColors.White,
+                    style = MaterialTheme.typography.labelSmall,
+                    textAlign = TextAlign.Center)
             }
         }
     }
diff --git a/app/src/main/java/com/example/ssau_schedule/MainActivity.kt b/app/src/main/java/com/example/ssau_schedule/MainActivity.kt
new file mode 100644
index 0000000..b1ffda6
--- /dev/null
+++ b/app/src/main/java/com/example/ssau_schedule/MainActivity.kt
@@ -0,0 +1,50 @@
+package com.example.ssau_schedule
+
+import android.os.Bundle
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.imePadding
+import androidx.compose.foundation.layout.navigationBarsPadding
+import androidx.compose.foundation.layout.statusBarsPadding
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.core.view.WindowCompat
+import com.example.ssau_schedule.api.Http
+import com.example.ssau_schedule.ui.theme.SSAU_ScheduleTheme
+
+class MainActivity : ComponentActivity() {
+    private val http = Http()
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        enableEdgeToEdge()
+
+        WindowCompat.setDecorFitsSystemWindows(window, false)
+
+        setContent {
+            SSAU_ScheduleTheme {
+                MainPage()
+            }
+        }
+    }
+
+    @Composable
+    fun MainPage() {
+        Box(
+            Modifier
+                .background(MaterialTheme.colorScheme.background)
+                .fillMaxSize()
+                .statusBarsPadding()
+                .navigationBarsPadding()
+                .imePadding(),
+        ) {
+            Text("main page")
+        }
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/api/Auth.kt b/app/src/main/java/com/example/ssau_schedule/api/Auth.kt
index 91d1d47..0857025 100644
--- a/app/src/main/java/com/example/ssau_schedule/api/Auth.kt
+++ b/app/src/main/java/com/example/ssau_schedule/api/Auth.kt
@@ -1,19 +1,14 @@
 package com.example.ssau_schedule.api
 
-import android.annotation.SuppressLint
 import android.content.Context
-import androidx.datastore.preferences.core.edit
 import com.example.ssau_schedule.BuildConfig
 import com.example.ssau_schedule.R
-import com.example.ssau_schedule.data.source.AuthStoreKeys
-import com.example.ssau_schedule.data.source.authStore
+import com.example.ssau_schedule.data.store.AuthStore
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.launch
 import okhttp3.Headers.Companion.toHeaders
 import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.RequestBody.Companion.toRequestBody
 import okhttp3.Response
-import okio.IOException
 import org.json.JSONArray
 
 enum class AuthErrorMessage(private val resource: Int) {
@@ -25,63 +20,48 @@ enum class AuthErrorMessage(private val resource: Int) {
         context.getString(resource)
 }
 
-class AuthorizationAPI(private var http: Http, private var context: Context) {
-    companion object {
-        @SuppressLint("StaticFieldLeak")
-        @Volatile
-        private var INSTANCE: AuthorizationAPI? = null
-        fun getInstance(http: Http, context: Context) =
-            INSTANCE ?: synchronized(this) {
-                INSTANCE ?: AuthorizationAPI(http, context).also {
-                    INSTANCE = it
-                }
-            }
-    }
-
+class AuthorizationAPI(
+    private var http: Http,
+    private var context: Context,
+    private var scope: CoroutineScope
+) {
     private val responseHasAuthToken =
-        {response: Response? -> response?.headers?.toMap()?.containsKey("set-cookie") == true}
+        { response: Response? -> response?.headers?.toMap()?.containsKey("set-cookie") == true }
 
-    private fun safeAuthToken(response: Response,
-                              authScope: CoroutineScope,
-                              callback: HttpResponseCallback) {
-        authScope.launch {
-            context.authStore.edit { authStore ->
-                authStore[AuthStoreKeys.AUTH_TOKEN] =
-                    response.headers("set-cookie").joinToString(", ")
-            }.run {
-                callback(response)
-            }
-        }
-    }
-
-    fun signIn(login: String, password: String, authScope: CoroutineScope,
-               callback: HttpResponseCallback,
-               exceptionCallback: HttpExceptionCallback? = null) {
+    fun signIn(
+        login: String, password: String,
+        callback: (token: String) -> Unit,
+        exceptionCallback: ((error: HttpRequestException) -> Unit)? = null
+    ) {
         http.request(
             Method.POST,
             BuildConfig.SIGN_IN_URL,
-            JSONArray(arrayOf(mapOf(
-                Pair("login", login),
-                Pair("password", password)
-            ))).toString().toRequestBody("application/json".toMediaType()),
+            JSONArray(
+                arrayOf(
+                    mapOf(
+                        Pair("login", login),
+                        Pair("password", password)
+                    )
+                )
+            ).toString().toRequestBody("application/json".toMediaType()),
             mapOf(
                 Pair("Next-Action", "b395d17834d8b7df06372cbf1f241170a272d540")
             ).toHeaders(),
             fun(response) {
-                if(responseHasAuthToken(response))
-                    safeAuthToken(response, authScope, callback)
-                else if(exceptionCallback != null)
-                    exceptionCallback(IOException("Authorization token not found"), response)
+                if (responseHasAuthToken(response)) {
+                    val token = response.headers("set-cookie").joinToString(", ")
+                    AuthStore.setAuthToken(token, context, scope) { callback(token) }
+                } else
+                    exceptionCallback?.invoke(
+                        HttpRequestException("Authorization token not found"))
             },
-            fun (error, response): Boolean {
-                if(responseHasAuthToken(response)) return true
-                if(exceptionCallback !== null) exceptionCallback(error, response)
+            fun(error, response): Boolean {
+                if (responseHasAuthToken(response)) return true
+                exceptionCallback?.invoke(error)
                 return false
             }
         )
     }
 
 
-
-
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/api/General.kt b/app/src/main/java/com/example/ssau_schedule/api/General.kt
new file mode 100644
index 0000000..fbeff02
--- /dev/null
+++ b/app/src/main/java/com/example/ssau_schedule/api/General.kt
@@ -0,0 +1,189 @@
+package com.example.ssau_schedule.api
+
+import android.content.Context
+import android.util.Log
+import com.example.ssau_schedule.BuildConfig
+import com.example.ssau_schedule.R
+import com.example.ssau_schedule.data.store.AuthStore
+import com.example.ssau_schedule.data.store.Group
+import com.example.ssau_schedule.data.store.RawYear
+import com.example.ssau_schedule.data.store.User
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.serialization.SerializationException
+import kotlinx.serialization.json.Json
+import okhttp3.Headers.Companion.toHeaders
+
+
+enum class ApiErrorMessage(private val resource: Int?) {
+    FAILED_GET_USER_DETAILS(R.string.failder_get_user_details),
+    NOT_MEMBER_OF_ANY_GROUP(R.string.not_member_of_any_group),
+    FAILED_GET_USER_GROUPS(R.string.failed_get_user_groups),
+    FAILED_GET_YEARS(R.string.failed_get_years),
+
+    USER_NOT_AUTHORIZED(null);
+
+    fun getMessage(context: Context) =
+        if(resource != null) context.getString(resource) else null
+}
+
+class GeneralApi(
+    private var http: Http,
+    private var context: Context,
+    private var scope: CoroutineScope
+) {
+    fun getUserDetails(
+        token: String,
+        callback: (user: User) -> Unit,
+        exceptionCallback: ((error: ApiErrorMessage) -> Unit)
+    ) {
+        http.request(
+            Method.GET,
+            BuildConfig.USER_DETAILS_URL,
+            mapOf(
+                Pair("Cookie", token)
+            ).toHeaders(),
+            { response ->
+                try {
+                    if(response.body != null) {
+                        val serializer = Json {
+                            isLenient = true
+                            ignoreUnknownKeys = true
+                        }
+                        callback(serializer
+                            .decodeFromString<User>(response.body!!.string()))
+                    }
+                    else exceptionCallback(ApiErrorMessage.FAILED_GET_USER_DETAILS)
+                }
+                catch(e: SerializationException) {
+                    Log.e("Groups Deserialization exception", e.message ?: "")
+                    exceptionCallback(ApiErrorMessage.FAILED_GET_USER_DETAILS)
+                }
+                catch (e: IllegalArgumentException) {
+                    Log.e("Groups argument exception", e.message ?: "")
+                    exceptionCallback(ApiErrorMessage.FAILED_GET_USER_DETAILS)
+                }
+            },
+            fun(_, r): Boolean {
+                if(r?.code == 401) exceptionCallback(ApiErrorMessage.USER_NOT_AUTHORIZED)
+                else exceptionCallback(ApiErrorMessage.FAILED_GET_USER_DETAILS)
+                return false
+            }
+        )
+    }
+    fun getUserDetails(
+        callback: (user: User) -> Unit,
+        exceptionCallback: ((error: ApiErrorMessage) -> Unit)
+    ) {
+        AuthStore.getAuthToken(context, scope) { authToken ->
+            if(authToken != null)
+                getUserDetails(authToken, callback, exceptionCallback)
+            else exceptionCallback(ApiErrorMessage.USER_NOT_AUTHORIZED)
+        }
+    }
+
+    fun getUserGroups(
+        token: String,
+        callback: (groups: List<Group>) -> Unit,
+        exceptionCallback: (error: ApiErrorMessage) -> Unit
+    ) {
+        http.request(
+            Method.GET,
+            BuildConfig.USER_GROUPS_URL,
+            mapOf(
+                Pair("Cookie", token)
+            ).toHeaders(),
+            { response ->
+                try {
+                    if(response.body != null) {
+                        val serializer = Json {
+                            isLenient = true
+                            ignoreUnknownKeys = true
+                        }
+                        val groups = serializer
+                            .decodeFromString<List<Group>>(response.body!!.string())
+                        if(groups.isNotEmpty()) callback(groups)
+                        else { exceptionCallback(ApiErrorMessage.NOT_MEMBER_OF_ANY_GROUP) }
+                    }
+                    else exceptionCallback(ApiErrorMessage.FAILED_GET_USER_GROUPS)
+                }
+                catch(e: SerializationException) {
+                    Log.e("Groups Deserialization exception", e.message ?: "")
+                    exceptionCallback(ApiErrorMessage.FAILED_GET_USER_GROUPS)
+                }
+                catch (e: IllegalArgumentException) {
+                    Log.e("Groups argument exception", e.message ?: "")
+                    exceptionCallback(ApiErrorMessage.FAILED_GET_USER_GROUPS)
+                }
+            },
+            fun(_, r): Boolean {
+                if(r?.code == 401) exceptionCallback(ApiErrorMessage.USER_NOT_AUTHORIZED)
+                else exceptionCallback(ApiErrorMessage.FAILED_GET_USER_GROUPS)
+                return false
+            }
+        )
+    }
+
+    fun getUserGroups(
+        callback: (groups: List<Group>) -> Unit,
+        exceptionCallback: (error: ApiErrorMessage) -> Unit
+    ) {
+        AuthStore.getAuthToken(context, scope) { authToken ->
+            if(authToken != null)
+                getUserGroups(authToken, callback, exceptionCallback)
+            else exceptionCallback(ApiErrorMessage.USER_NOT_AUTHORIZED)
+        }
+    }
+
+    fun getYears(
+        token: String,
+        callback: (rawYears: List<RawYear>) -> Unit,
+        exceptionCallback: (error: ApiErrorMessage) -> Unit
+    ) {
+        http.request(
+            Method.GET,
+            BuildConfig.YEARS_URL,
+            mapOf(
+                Pair("Cookie", token)
+            ).toHeaders(),
+            { response ->
+                try {
+                    if(response.body != null) {
+                        val serializer = Json {
+                            isLenient = true
+                            ignoreUnknownKeys = true
+                        }
+                        val rawYears = serializer
+                            .decodeFromString<List<RawYear>>(response.body!!.string())
+                        if(rawYears.isNotEmpty()) callback(rawYears)
+                        else { exceptionCallback(ApiErrorMessage.FAILED_GET_YEARS) }
+                    }
+                    else exceptionCallback(ApiErrorMessage.FAILED_GET_YEARS)
+                }
+                catch(e: SerializationException) {
+                    Log.e("Groups Deserialization exception", e.message ?: "")
+                    exceptionCallback(ApiErrorMessage.FAILED_GET_YEARS)
+                }
+                catch (e: IllegalArgumentException) {
+                    Log.e("Groups argument exception", e.message ?: "")
+                    exceptionCallback(ApiErrorMessage.FAILED_GET_YEARS)
+                }
+            },
+            fun(_, r): Boolean {
+                if(r?.code == 401) exceptionCallback(ApiErrorMessage.USER_NOT_AUTHORIZED)
+                else exceptionCallback(ApiErrorMessage.FAILED_GET_YEARS)
+                return false
+            }
+        )
+    }
+
+    fun getYears(
+        callback: (rawYears: List<RawYear>) -> Unit,
+        exceptionCallback: (error: ApiErrorMessage) -> Unit
+    ) {
+        AuthStore.getAuthToken(context, scope) { authToken ->
+            if(authToken != null)
+                getYears(authToken, callback, exceptionCallback)
+            else exceptionCallback(ApiErrorMessage.USER_NOT_AUTHORIZED)
+        }
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/api/Http.kt b/app/src/main/java/com/example/ssau_schedule/api/Http.kt
index c9b046f..626799e 100644
--- a/app/src/main/java/com/example/ssau_schedule/api/Http.kt
+++ b/app/src/main/java/com/example/ssau_schedule/api/Http.kt
@@ -9,7 +9,7 @@ import okhttp3.OkHttpClient
 import okhttp3.Request
 import okhttp3.RequestBody
 import okhttp3.Response
-import java.io.IOException
+import okio.IOException
 
 enum class Method {
     GET,
@@ -18,9 +18,14 @@ enum class Method {
     DELETE
 }
 
-typealias HttpResponseCallback = (response: Response) -> Unit
-typealias HttpExceptionVerifyCallback = (exception: IOException, response: Response?) -> Boolean
-typealias HttpExceptionCallback = (exception: IOException, response: Response?) -> Unit
+typealias HttpRequestException = IOException
+
+typealias HttpResponseCallback =
+            (response: Response) -> Unit
+typealias HttpExceptionVerifyCallback =
+            (exception: HttpRequestException, response: Response?) -> Boolean
+typealias HttpExceptionCallback =
+            (exception: HttpRequestException, response: Response?) -> Unit
 
 class Http {
     val http = OkHttpClient()
@@ -33,22 +38,38 @@ class Http {
         callback: HttpResponseCallback,
         exceptionCallback: HttpExceptionVerifyCallback? = null
     ) {
-        val request = Request.Builder().url(BuildConfig.BASE_URL+url).
-                                                method(method.toString(), body)
-        if(headers !== null) request.headers(headers)
+        val request =
+            Request.Builder().url(BuildConfig.BASE_URL + url).method(method.toString(), body)
+        if (headers !== null) request.headers(headers)
         http.newCall(request.build()).enqueue(object : Callback {
-            override fun onFailure(call: Call, e: IOException) {
+            override fun onFailure(call: Call, e: HttpRequestException) {
                 Log.e("Http request failed", e.toString())
-                if(exceptionCallback !== null) exceptionCallback(e, null)
+                exceptionCallback?.invoke(e, null)
             }
 
             override fun onResponse(call: Call, response: Response) {
                 var runCallback = false
                 if (!response.isSuccessful && exceptionCallback !== null)
                     runCallback = exceptionCallback(
-                        IOException("Http response is not successful"), response)
-                if(runCallback || response.isSuccessful) callback(response)
+                        HttpRequestException("Http response is not successful"), response
+                    )
+                if (runCallback || response.isSuccessful) callback(response)
             }
         })
     }
+
+    fun request(
+        method: Method,
+        url: String,
+        headers: Headers? = null,
+        callback: HttpResponseCallback,
+        exceptionCallback: HttpExceptionVerifyCallback? = null
+    ) = request(method, url, null, headers, callback, exceptionCallback)
+
+    fun request(
+        method: Method,
+        url: String,
+        callback: HttpResponseCallback,
+        exceptionCallback: HttpExceptionVerifyCallback? = null
+    ) = request(method, url, null, null, callback, exceptionCallback)
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/data/source/Auth.kt b/app/src/main/java/com/example/ssau_schedule/data/source/Auth.kt
deleted file mode 100644
index 5f57ae2..0000000
--- a/app/src/main/java/com/example/ssau_schedule/data/source/Auth.kt
+++ /dev/null
@@ -1,11 +0,0 @@
-package com.example.ssau_schedule.data.source
-
-import android.content.Context
-import androidx.datastore.preferences.core.stringPreferencesKey
-import androidx.datastore.preferences.preferencesDataStore
-
-val Context.authStore by preferencesDataStore(name = "auth")
-
-object AuthStoreKeys {
-    val AUTH_TOKEN = stringPreferencesKey("auth_token")
-}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/data/store/Auth.kt b/app/src/main/java/com/example/ssau_schedule/data/store/Auth.kt
new file mode 100644
index 0000000..b78b2d8
--- /dev/null
+++ b/app/src/main/java/com/example/ssau_schedule/data/store/Auth.kt
@@ -0,0 +1,49 @@
+package com.example.ssau_schedule.data.store
+
+import android.content.Context
+import androidx.datastore.preferences.core.edit
+import androidx.datastore.preferences.core.stringPreferencesKey
+import androidx.datastore.preferences.preferencesDataStore
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
+
+val Context.authStore by preferencesDataStore(name = "auth")
+
+class AuthStore {
+    class Keys {
+        companion object {
+            val AUTH_TOKEN = stringPreferencesKey("auth_token")
+        }
+    }
+
+    companion object {
+        fun setAuthToken(
+            token: String,
+            context: Context,
+            scope: CoroutineScope,
+            callback: (() -> Unit)? = null
+        ) {
+            scope.launch {
+                context.authStore.edit { authStore ->
+                    authStore[Keys.AUTH_TOKEN] = token
+                }.run { callback?.invoke() }
+            }
+        }
+
+        fun getAuthToken(
+            context: Context,
+            scope: CoroutineScope,
+            callback: (token: String?) -> Unit
+        ) {
+            scope.launch {
+                val authTokenFlow = context.authStore.data
+                    .map { authStore -> authStore[Keys.AUTH_TOKEN] }
+                callback(authTokenFlow.first())
+            }
+        }
+    }
+
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/data/store/General.kt b/app/src/main/java/com/example/ssau_schedule/data/store/General.kt
new file mode 100644
index 0000000..850190b
--- /dev/null
+++ b/app/src/main/java/com/example/ssau_schedule/data/store/General.kt
@@ -0,0 +1,156 @@
+package com.example.ssau_schedule.data.store
+
+import android.annotation.SuppressLint
+import android.content.Context
+import androidx.datastore.preferences.core.edit
+import androidx.datastore.preferences.core.intPreferencesKey
+import androidx.datastore.preferences.core.stringPreferencesKey
+import androidx.datastore.preferences.preferencesDataStore
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
+import kotlinx.serialization.Serializable
+import java.text.SimpleDateFormat
+import java.util.Calendar
+import java.util.Date
+
+val Context.generalStore by preferencesDataStore(name = "user")
+
+@Serializable
+data class User(val name: String)
+
+@Serializable
+data class Group(val id: Int, val name: String)
+
+data class Year(
+    val id: Int,
+    val startDate: Date,
+    val endDate: Date,
+) {
+    companion object {
+        @SuppressLint("SimpleDateFormat")
+        val DateFormat = SimpleDateFormat("yyyy-MM-dd")
+
+        fun parseDate(dateString: String): Date = DateFormat.parse(dateString)!!
+        fun dateFormat(date: Date): String = DateFormat.format(date)
+    }
+
+    fun hasDate(date: Date) = date.after(startDate) && endDate.after(date)
+    fun getWeekOfDate(date: Date): Int {
+        val calendar = Calendar.getInstance()
+        calendar.minimalDaysInFirstWeek = 6
+        calendar.firstDayOfWeek = Calendar.MONDAY
+        calendar.time = startDate
+        val firstWeek = calendar.get(Calendar.WEEK_OF_YEAR)
+        calendar.time = date
+        return (calendar.get(Calendar.WEEK_OF_YEAR) - firstWeek)+1
+    }
+
+}
+
+@Serializable
+data class RawYear(
+    val id: Int,
+    val startDate: String,
+    val endDate: String,
+    val isCurrent: Boolean,
+) {
+    @SuppressLint("SimpleDateFormat")
+    fun toYear() = Year(
+        id = id,
+        startDate = Year.parseDate(startDate),
+        endDate = Year.parseDate(endDate),
+    )
+}
+
+class GeneralStore {
+    class Keys {
+        companion object {
+            val CURRENT_GROUP_ID = intPreferencesKey("group_id")
+            val CURRENT_GROUP_NAME = stringPreferencesKey("group_name")
+
+            val CURRENT_YEAR_ID = intPreferencesKey("year_id")
+            val CURRENT_YEAR_START = stringPreferencesKey("year_start")
+            val CURRENT_YEAR_END = stringPreferencesKey("year_end")
+        }
+    }
+
+    companion object {
+        fun setCurrentGroup(
+            group: Group,
+            context: Context,
+            scope: CoroutineScope,
+            callback: (() -> Unit)? = null
+        ) {
+            scope.launch {
+                context.generalStore.edit { generalStore ->
+                    generalStore[Keys.CURRENT_GROUP_ID] = group.id
+                    generalStore[Keys.CURRENT_GROUP_NAME] = group.name
+                }.run { callback?.invoke() }
+            }
+        }
+
+        fun getCurrentGroup(
+            context: Context,
+            scope: CoroutineScope,
+            callback: (group: Group?) -> Unit
+        ) {
+            scope.launch {
+                val currentGroupId = context.generalStore.data
+                    .map { generalStore -> generalStore[Keys.CURRENT_GROUP_ID] }.first()
+                val currentGroupName = context.generalStore.data
+                    .map { generalStore -> generalStore[Keys.CURRENT_GROUP_NAME] }.first()
+                callback(
+                    if(currentGroupId != null && currentGroupName != null)
+                        Group(id = currentGroupId,
+                            name = currentGroupName)
+                    else null
+                )
+            }
+        }
+
+        fun setCurrentYear(
+            year: Year,
+            context: Context,
+            scope: CoroutineScope,
+            callback: (() -> Unit)? = null
+        ) {
+            scope.launch {
+                context.generalStore.edit { generalStore ->
+                    generalStore[Keys.CURRENT_YEAR_ID] = year.id
+                    generalStore[Keys.CURRENT_YEAR_START] = Year.dateFormat(year.startDate)
+                    generalStore[Keys.CURRENT_YEAR_END] = Year.dateFormat(year.endDate)
+                }.run { callback?.invoke() }
+            }
+        }
+
+        fun getCurrentYear(
+            context: Context,
+            scope: CoroutineScope,
+            callback: (year: Year?) -> Unit
+        ) {
+            scope.launch {
+                val currentYearId = context.generalStore.data
+                    .map { generalStore -> generalStore[Keys.CURRENT_YEAR_ID] }.first()
+                val currentYearStartDate = context.generalStore.data
+                    .map { generalStore -> generalStore[Keys.CURRENT_YEAR_START]
+                    }.first()
+                val currentYearEndDate = context.generalStore.data
+                    .map { generalStore -> generalStore[Keys.CURRENT_YEAR_END]
+                    }.first()
+                callback(
+                    if(currentYearId != null &&
+                            currentYearStartDate != null &&
+                            currentYearEndDate != null)
+                        Year(id = currentYearId,
+                            startDate = Year.parseDate(currentYearStartDate),
+                            endDate = Year.parseDate(currentYearEndDate))
+                    else null
+                )
+            }
+        }
+    }
+
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/ui/theme/Color.kt b/app/src/main/java/com/example/ssau_schedule/ui/theme/Color.kt
index 4ae8aa2..af21a81 100644
--- a/app/src/main/java/com/example/ssau_schedule/ui/theme/Color.kt
+++ b/app/src/main/java/com/example/ssau_schedule/ui/theme/Color.kt
@@ -2,17 +2,24 @@ package com.example.ssau_schedule.ui.theme
 
 import androidx.compose.ui.graphics.Color
 
-val Primary01 = Color(0xFF0D47A1)
-val Primary02 = Color(0xFF134BC5)
-val Primary03 = Color(0xFF1D5DEB)
-val Primary04 = Color(0xFF2780E3)
-val Primary05 = Color(0xFF6B92E5)
-val Primary06 = Color(0xFFA8C4EC)
+class ApplicationColors {
+    companion object {
+        val Primary01 = Color(0xFF0D47A1)
+        val Primary02 = Color(0xFF134BC5)
+        val Primary03 = Color(0xFF1D5DEB)
+        val Primary04 = Color(0xFF2780E3)
+        val Primary05 = Color(0xFF6B92E5)
+        val Primary06 = Color(0xFFA8C4EC)
 
-val White = Color(0xFFFFFFFF)
+        val White = Color(0xFFFFFFFF)
+
+        val Gray01 = Color(0xFF2C2C2C)
+        val Gray02 = Color(0xFF383838)
+        val Gray03 = Color(0xFF66727F)
+
+        val Red01 = Color(0xFFEE3F58)
+        val Red02 = Color(0xFF7E212E)
+    }
+}
 
-val Gray01 = Color(0xFF2C2C2C)
-val Gray02 = Color(0xFF383838)
-val Gray03 = Color(0xFF66727F)
 
-val Red = Color(0xFFEE3F58)
\ No newline at end of file
diff --git a/app/src/main/java/com/example/ssau_schedule/ui/theme/Theme.kt b/app/src/main/java/com/example/ssau_schedule/ui/theme/Theme.kt
index fbe7361..dc5da4e 100644
--- a/app/src/main/java/com/example/ssau_schedule/ui/theme/Theme.kt
+++ b/app/src/main/java/com/example/ssau_schedule/ui/theme/Theme.kt
@@ -12,21 +12,23 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.platform.LocalContext
 
 private val DarkColorScheme = darkColorScheme(
-    primary = Primary01,
-    secondary = Primary03,
-    tertiary = Primary04,
-    background = Gray01,
-    surface = Gray02,
-    error = Red,
+    primary = ApplicationColors.Primary01,
+    secondary = ApplicationColors.Primary03,
+    tertiary = ApplicationColors.Primary04,
+    background = ApplicationColors.Gray01,
+    surface = ApplicationColors.Gray02,
+    error = ApplicationColors.Red01,
+    errorContainer = ApplicationColors.Red02
 )
 
 private val LightColorScheme = lightColorScheme(
-    primary = Primary01,
-    secondary = Primary03,
-    tertiary = Primary04,
-    background = White,
-    surface = Primary06,
-    error = Red,
+    primary = ApplicationColors.Primary01,
+    secondary = ApplicationColors.Primary03,
+    tertiary = ApplicationColors.Primary04,
+    background = ApplicationColors.White,
+    surface = ApplicationColors.Primary06,
+    error = ApplicationColors.Red01,
+    errorContainer = ApplicationColors.Red02
 
     /* Other default colors to override
     background = Color(0xFFFFFBFE),
diff --git a/app/src/main/res/values-en/strings.xml b/app/src/main/res/values-en/strings.xml
index 6448f45..23e0b38 100644
--- a/app/src/main/res/values-en/strings.xml
+++ b/app/src/main/res/values-en/strings.xml
@@ -10,4 +10,8 @@
     <string name="incorrect_login_or_password">Incorrect login or password</string>
     <string name="login_is_too_short">Login is too short</string>
     <string name="password_is_too_short">Password is too short</string>
+    <string name="not_member_of_any_group">The user is not a member of any study group. You can\'t get a schedule for him</string>
+    <string name="failed_get_user_groups">Не получилось получить список групп, в которых состоит пользователь. Расписание нельзя получить без учебной группы</string>
+    <string name="failed_get_years">It was not possible to obtain a list of academic years. The timetable cannot be obtained without the academic year</string>
+    <string name="failder_get_user_details">Failed to retrieve user information. The schedule cannot be obtained without user data</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 1bae4a6..d8bb060 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -9,4 +9,8 @@
     <string name="incorrect_login_or_password">Неверный логин или пароль</string>
     <string name="login_is_too_short">Логин слишком короткий</string>
     <string name="password_is_too_short">Пароль слишком короткий</string>
+    <string name="not_member_of_any_group">Пользователь не состоит ни в одной учебной группе. Для него нельзя получить расписание</string>
+    <string name="failed_get_user_groups">Не получилось получить список групп, в которых состоит пользователь. Расписание нельзя получить без учебной группы</string>
+    <string name="failed_get_years">Не получилось получить список учебных годов. Расписание нельзя получить без учебного года</string>
+    <string name="failder_get_user_details">Не получилось получить информацию о пользователе. Расписание нельзя получить без пользовательских данных</string>
 </resources>
\ No newline at end of file
diff --git a/build.gradle.kts b/build.gradle.kts
index b2c8728..ff5d0eb 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -2,5 +2,6 @@
 plugins {
     alias(libs.plugins.android.application) apply false
     alias(libs.plugins.kotlin.android) apply false
+    alias(libs.plugins.kotlin.serialization) apply false
     alias(libs.plugins.compose.compiler) apply false
 }
\ No newline at end of file
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 541555c..a2cf554 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -11,6 +11,7 @@ composeBom = "2024.09.00"
 okhttp = "4.12.0"
 datastore = "1.1.1"
 media3Common = "1.4.1"
+kotlinSerializationJson = "1.7.1"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -30,8 +31,10 @@ androidx-material3 = { group = "androidx.compose.material3", name = "material3"
 squareup-okhttp = { group = "com.squareup.okhttp3", name = "okhttp", version.ref = "okhttp" }
 androidx-datastore = { group = "androidx.datastore", name="datastore-preferences", version.ref = "datastore" }
 androidx-media3-common = { group = "androidx.media3", name = "media3-common", version.ref = "media3Common" }
+kotlinx-serialization-json = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json", version.ref = "kotlinSerializationJson" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
 compose-compiler = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
+kotlin-serialization = { id = "org.jetbrains.kotlin.plugin.serialization", version.ref = "kotlin" }