diff --git a/app/schemas/agzam.vyatsu.data.local.AppDatabase/4.json b/app/schemas/agzam.vyatsu.data.local.AppDatabase/4.json
new file mode 100644
index 0000000..b443070
--- /dev/null
+++ b/app/schemas/agzam.vyatsu.data.local.AppDatabase/4.json
@@ -0,0 +1,818 @@
+{
+  "formatVersion": 1,
+  "database": {
+    "version": 4,
+    "identityHash": "38abab3f8c5b39625b6a4de9d58968ca",
+    "entities": [
+      {
+        "tableName": "groups",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` TEXT NOT NULL, `name` TEXT NOT NULL, `faculty` TEXT NOT NULL, `lastSyncedAt` INTEGER NOT NULL, PRIMARY KEY(`id`))",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "name",
+            "columnName": "name",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "faculty",
+            "columnName": "faculty",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "lastSyncedAt",
+            "columnName": "lastSyncedAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": false,
+          "columnNames": [
+            "id"
+          ]
+        }
+      },
+      {
+        "tableName": "group_periods",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `groupId` TEXT NOT NULL, `season` TEXT NOT NULL, `weekStart` INTEGER NOT NULL, `weekEnd` INTEGER NOT NULL, FOREIGN KEY(`groupId`) REFERENCES `groups`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "groupId",
+            "columnName": "groupId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "season",
+            "columnName": "season",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekStart",
+            "columnName": "weekStart",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekEnd",
+            "columnName": "weekEnd",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_group_periods_groupId",
+            "unique": false,
+            "columnNames": [
+              "groupId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_group_periods_groupId` ON `${TABLE_NAME}` (`groupId`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "groups",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "groupId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "schedules",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `groupId` TEXT NOT NULL, `season` TEXT NOT NULL, `weekStart` INTEGER NOT NULL, `weekEnd` INTEGER NOT NULL, `lastSyncedAt` INTEGER NOT NULL, FOREIGN KEY(`groupId`) REFERENCES `groups`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "groupId",
+            "columnName": "groupId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "season",
+            "columnName": "season",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekStart",
+            "columnName": "weekStart",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekEnd",
+            "columnName": "weekEnd",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "lastSyncedAt",
+            "columnName": "lastSyncedAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_schedules_groupId",
+            "unique": false,
+            "columnNames": [
+              "groupId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_schedules_groupId` ON `${TABLE_NAME}` (`groupId`)"
+          },
+          {
+            "name": "index_schedules_groupId_season_weekStart",
+            "unique": true,
+            "columnNames": [
+              "groupId",
+              "season",
+              "weekStart"
+            ],
+            "orders": [],
+            "createSql": "CREATE UNIQUE INDEX IF NOT EXISTS `index_schedules_groupId_season_weekStart` ON `${TABLE_NAME}` (`groupId`, `season`, `weekStart`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "groups",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "groupId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "days",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `scheduleId` INTEGER NOT NULL, `date` INTEGER NOT NULL, FOREIGN KEY(`scheduleId`) REFERENCES `schedules`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "scheduleId",
+            "columnName": "scheduleId",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "date",
+            "columnName": "date",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_days_scheduleId",
+            "unique": false,
+            "columnNames": [
+              "scheduleId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_days_scheduleId` ON `${TABLE_NAME}` (`scheduleId`)"
+          },
+          {
+            "name": "index_days_date",
+            "unique": false,
+            "columnNames": [
+              "date"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_days_date` ON `${TABLE_NAME}` (`date`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "schedules",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "scheduleId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "lessons",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `dayId` INTEGER NOT NULL, `date` INTEGER NOT NULL, `slotIndex` INTEGER NOT NULL, `start` INTEGER NOT NULL, `end` INTEGER NOT NULL, `lessonIndex` INTEGER NOT NULL, `raw` TEXT NOT NULL, `room` TEXT, `groupName` TEXT, `subgroup` TEXT, `subject` TEXT, `type` TEXT NOT NULL, `teacher` TEXT, FOREIGN KEY(`dayId`) REFERENCES `days`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "dayId",
+            "columnName": "dayId",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "date",
+            "columnName": "date",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "slotIndex",
+            "columnName": "slotIndex",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "start",
+            "columnName": "start",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "end",
+            "columnName": "end",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "lessonIndex",
+            "columnName": "lessonIndex",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "raw",
+            "columnName": "raw",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "room",
+            "columnName": "room",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "groupName",
+            "columnName": "groupName",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "subgroup",
+            "columnName": "subgroup",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "subject",
+            "columnName": "subject",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "type",
+            "columnName": "type",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "teacher",
+            "columnName": "teacher",
+            "affinity": "TEXT"
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_lessons_dayId",
+            "unique": false,
+            "columnNames": [
+              "dayId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_lessons_dayId` ON `${TABLE_NAME}` (`dayId`)"
+          },
+          {
+            "name": "index_lessons_date",
+            "unique": false,
+            "columnNames": [
+              "date"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_lessons_date` ON `${TABLE_NAME}` (`date`)"
+          },
+          {
+            "name": "index_lessons_subject",
+            "unique": false,
+            "columnNames": [
+              "subject"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_lessons_subject` ON `${TABLE_NAME}` (`subject`)"
+          },
+          {
+            "name": "index_lessons_room",
+            "unique": false,
+            "columnNames": [
+              "room"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_lessons_room` ON `${TABLE_NAME}` (`room`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "days",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "dayId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "preferences",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`key` TEXT NOT NULL, `value` TEXT NOT NULL, PRIMARY KEY(`key`))",
+        "fields": [
+          {
+            "fieldPath": "key",
+            "columnName": "key",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "value",
+            "columnName": "value",
+            "affinity": "TEXT",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": false,
+          "columnNames": [
+            "key"
+          ]
+        }
+      },
+      {
+        "tableName": "departments",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`departmentId` TEXT NOT NULL, `name` TEXT NOT NULL, `faculty` TEXT NOT NULL, `lastSyncedAt` INTEGER NOT NULL, PRIMARY KEY(`departmentId`))",
+        "fields": [
+          {
+            "fieldPath": "departmentId",
+            "columnName": "departmentId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "name",
+            "columnName": "name",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "faculty",
+            "columnName": "faculty",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "lastSyncedAt",
+            "columnName": "lastSyncedAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": false,
+          "columnNames": [
+            "departmentId"
+          ]
+        }
+      },
+      {
+        "tableName": "department_periods",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `departmentId` TEXT NOT NULL, `season` TEXT NOT NULL, `weekStart` INTEGER NOT NULL, `weekEnd` INTEGER NOT NULL, FOREIGN KEY(`departmentId`) REFERENCES `departments`(`departmentId`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "departmentId",
+            "columnName": "departmentId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "season",
+            "columnName": "season",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekStart",
+            "columnName": "weekStart",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekEnd",
+            "columnName": "weekEnd",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_department_periods_departmentId",
+            "unique": false,
+            "columnNames": [
+              "departmentId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_department_periods_departmentId` ON `${TABLE_NAME}` (`departmentId`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "departments",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "departmentId"
+            ],
+            "referencedColumns": [
+              "departmentId"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "teacher_schedules",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `departmentId` TEXT NOT NULL, `season` TEXT NOT NULL, `weekStart` INTEGER NOT NULL, `weekEnd` INTEGER NOT NULL, `lastSyncedAt` INTEGER NOT NULL, FOREIGN KEY(`departmentId`) REFERENCES `departments`(`departmentId`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "departmentId",
+            "columnName": "departmentId",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "season",
+            "columnName": "season",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekStart",
+            "columnName": "weekStart",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "weekEnd",
+            "columnName": "weekEnd",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "lastSyncedAt",
+            "columnName": "lastSyncedAt",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_teacher_schedules_departmentId",
+            "unique": false,
+            "columnNames": [
+              "departmentId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_schedules_departmentId` ON `${TABLE_NAME}` (`departmentId`)"
+          },
+          {
+            "name": "index_teacher_schedules_departmentId_season_weekStart",
+            "unique": true,
+            "columnNames": [
+              "departmentId",
+              "season",
+              "weekStart"
+            ],
+            "orders": [],
+            "createSql": "CREATE UNIQUE INDEX IF NOT EXISTS `index_teacher_schedules_departmentId_season_weekStart` ON `${TABLE_NAME}` (`departmentId`, `season`, `weekStart`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "departments",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "departmentId"
+            ],
+            "referencedColumns": [
+              "departmentId"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "teacher_days",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `scheduleId` INTEGER NOT NULL, `date` INTEGER NOT NULL, FOREIGN KEY(`scheduleId`) REFERENCES `teacher_schedules`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "scheduleId",
+            "columnName": "scheduleId",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "date",
+            "columnName": "date",
+            "affinity": "INTEGER",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_teacher_days_scheduleId",
+            "unique": false,
+            "columnNames": [
+              "scheduleId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_days_scheduleId` ON `${TABLE_NAME}` (`scheduleId`)"
+          },
+          {
+            "name": "index_teacher_days_date",
+            "unique": false,
+            "columnNames": [
+              "date"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_days_date` ON `${TABLE_NAME}` (`date`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "teacher_schedules",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "scheduleId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      },
+      {
+        "tableName": "teacher_lessons",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `dayId` INTEGER NOT NULL, `date` INTEGER NOT NULL, `slotIndex` INTEGER NOT NULL, `start` INTEGER NOT NULL, `end` INTEGER NOT NULL, `lessonIndex` INTEGER NOT NULL, `raw` TEXT NOT NULL, `room` TEXT, `groupName` TEXT, `subgroup` TEXT, `subject` TEXT, `type` TEXT NOT NULL, `teacher` TEXT NOT NULL, FOREIGN KEY(`dayId`) REFERENCES `teacher_days`(`id`) ON UPDATE NO ACTION ON DELETE CASCADE )",
+        "fields": [
+          {
+            "fieldPath": "id",
+            "columnName": "id",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "dayId",
+            "columnName": "dayId",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "date",
+            "columnName": "date",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "slotIndex",
+            "columnName": "slotIndex",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "start",
+            "columnName": "start",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "end",
+            "columnName": "end",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "lessonIndex",
+            "columnName": "lessonIndex",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
+          {
+            "fieldPath": "raw",
+            "columnName": "raw",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "room",
+            "columnName": "room",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "groupName",
+            "columnName": "groupName",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "subgroup",
+            "columnName": "subgroup",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "subject",
+            "columnName": "subject",
+            "affinity": "TEXT"
+          },
+          {
+            "fieldPath": "type",
+            "columnName": "type",
+            "affinity": "TEXT",
+            "notNull": true
+          },
+          {
+            "fieldPath": "teacher",
+            "columnName": "teacher",
+            "affinity": "TEXT",
+            "notNull": true
+          }
+        ],
+        "primaryKey": {
+          "autoGenerate": true,
+          "columnNames": [
+            "id"
+          ]
+        },
+        "indices": [
+          {
+            "name": "index_teacher_lessons_dayId",
+            "unique": false,
+            "columnNames": [
+              "dayId"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_dayId` ON `${TABLE_NAME}` (`dayId`)"
+          },
+          {
+            "name": "index_teacher_lessons_teacher",
+            "unique": false,
+            "columnNames": [
+              "teacher"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_teacher` ON `${TABLE_NAME}` (`teacher`)"
+          },
+          {
+            "name": "index_teacher_lessons_room",
+            "unique": false,
+            "columnNames": [
+              "room"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_room` ON `${TABLE_NAME}` (`room`)"
+          },
+          {
+            "name": "index_teacher_lessons_subject",
+            "unique": false,
+            "columnNames": [
+              "subject"
+            ],
+            "orders": [],
+            "createSql": "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_subject` ON `${TABLE_NAME}` (`subject`)"
+          }
+        ],
+        "foreignKeys": [
+          {
+            "table": "teacher_days",
+            "onDelete": "CASCADE",
+            "onUpdate": "NO ACTION",
+            "columns": [
+              "dayId"
+            ],
+            "referencedColumns": [
+              "id"
+            ]
+          }
+        ]
+      }
+    ],
+    "setupQueries": [
+      "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)",
+      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, '38abab3f8c5b39625b6a4de9d58968ca')"
+    ]
+  }
+}
\ No newline at end of file
diff --git a/app/src/main/java/agzam/vyatsu/data/local/AppDatabase.kt b/app/src/main/java/agzam/vyatsu/data/local/AppDatabase.kt
index 76a8b7e..89f72df 100644
--- a/app/src/main/java/agzam/vyatsu/data/local/AppDatabase.kt
+++ b/app/src/main/java/agzam/vyatsu/data/local/AppDatabase.kt
@@ -3,6 +3,8 @@ package agzam.vyatsu.data.local
 import androidx.room.Database
 import androidx.room.RoomDatabase
 import androidx.room.TypeConverters
+import androidx.room.migration.Migration
+import androidx.sqlite.db.SupportSQLiteDatabase
 
 @Database(
     entities = [
@@ -11,9 +13,14 @@ import androidx.room.TypeConverters
         ScheduleEntity::class,
         DayEntity::class,
         LessonEntity::class,
-        PreferenceEntity::class
+        PreferenceEntity::class,
+        DepartmentEntity::class,
+        DepartmentPeriodEntity::class,
+        TeacherScheduleEntity::class,
+        TeacherDayEntity::class,
+        TeacherLessonEntity::class
     ],
-    version = 3,
+    version = 4,
     exportSchema = true
 )
 @TypeConverters(Converters::class)
@@ -21,4 +28,91 @@ abstract class AppDatabase : RoomDatabase() {
     abstract fun groupDao(): GroupDao
     abstract fun scheduleDao(): ScheduleDao
     abstract fun preferencesDao(): PreferencesDao
+    abstract fun teacherDao(): TeacherDao
+    abstract fun teacherScheduleDao(): TeacherScheduleDao
+
+    companion object {
+        val MIGRATION_3_4 = object : Migration(3, 4) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL(
+                    "CREATE TABLE IF NOT EXISTS `departments` (" +
+                        "`departmentId` TEXT NOT NULL, `name` TEXT NOT NULL, " +
+                        "`faculty` TEXT NOT NULL, `lastSyncedAt` INTEGER NOT NULL, " +
+                        "PRIMARY KEY(`departmentId`))"
+                )
+                db.execSQL(
+                    "CREATE TABLE IF NOT EXISTS `department_periods` (" +
+                        "`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, " +
+                        "`departmentId` TEXT NOT NULL, `season` TEXT NOT NULL, " +
+                        "`weekStart` INTEGER NOT NULL, `weekEnd` INTEGER NOT NULL, " +
+                        "FOREIGN KEY(`departmentId`) REFERENCES `departments`(`departmentId`) " +
+                        "ON UPDATE NO ACTION ON DELETE CASCADE )"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_department_periods_departmentId` " +
+                        "ON `department_periods` (`departmentId`)"
+                )
+                db.execSQL(
+                    "CREATE TABLE IF NOT EXISTS `teacher_schedules` (" +
+                        "`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, " +
+                        "`departmentId` TEXT NOT NULL, `season` TEXT NOT NULL, " +
+                        "`weekStart` INTEGER NOT NULL, `weekEnd` INTEGER NOT NULL, " +
+                        "`lastSyncedAt` INTEGER NOT NULL, " +
+                        "FOREIGN KEY(`departmentId`) REFERENCES `departments`(`departmentId`) " +
+                        "ON UPDATE NO ACTION ON DELETE CASCADE )"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_schedules_departmentId` " +
+                        "ON `teacher_schedules` (`departmentId`)"
+                )
+                db.execSQL(
+                    "CREATE UNIQUE INDEX IF NOT EXISTS `index_teacher_schedules_departmentId_season_weekStart` " +
+                        "ON `teacher_schedules` (`departmentId`, `season`, `weekStart`)"
+                )
+                db.execSQL(
+                    "CREATE TABLE IF NOT EXISTS `teacher_days` (" +
+                        "`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, " +
+                        "`scheduleId` INTEGER NOT NULL, `date` INTEGER NOT NULL, " +
+                        "FOREIGN KEY(`scheduleId`) REFERENCES `teacher_schedules`(`id`) " +
+                        "ON UPDATE NO ACTION ON DELETE CASCADE )"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_days_scheduleId` " +
+                        "ON `teacher_days` (`scheduleId`)"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_days_date` " +
+                        "ON `teacher_days` (`date`)"
+                )
+                db.execSQL(
+                    "CREATE TABLE IF NOT EXISTS `teacher_lessons` (" +
+                        "`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, " +
+                        "`dayId` INTEGER NOT NULL, `date` INTEGER NOT NULL, " +
+                        "`slotIndex` INTEGER NOT NULL, `start` INTEGER NOT NULL, " +
+                        "`end` INTEGER NOT NULL, `lessonIndex` INTEGER NOT NULL, " +
+                        "`raw` TEXT NOT NULL, `room` TEXT, `groupName` TEXT, " +
+                        "`subgroup` TEXT, `subject` TEXT, `type` TEXT NOT NULL, " +
+                        "`teacher` TEXT NOT NULL, " +
+                        "FOREIGN KEY(`dayId`) REFERENCES `teacher_days`(`id`) " +
+                        "ON UPDATE NO ACTION ON DELETE CASCADE )"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_dayId` " +
+                        "ON `teacher_lessons` (`dayId`)"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_teacher` " +
+                        "ON `teacher_lessons` (`teacher`)"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_room` " +
+                        "ON `teacher_lessons` (`room`)"
+                )
+                db.execSQL(
+                    "CREATE INDEX IF NOT EXISTS `index_teacher_lessons_subject` " +
+                        "ON `teacher_lessons` (`subject`)"
+                )
+            }
+        }
+    }
 }
diff --git a/app/src/main/java/agzam/vyatsu/data/local/DepartmentEntity.kt b/app/src/main/java/agzam/vyatsu/data/local/DepartmentEntity.kt
new file mode 100644
index 0000000..e81221b
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/DepartmentEntity.kt
@@ -0,0 +1,12 @@
+package agzam.vyatsu.data.local
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "departments")
+data class DepartmentEntity(
+    @PrimaryKey val departmentId: String,
+    val name: String,
+    val faculty: String,
+    val lastSyncedAt: Long
+)
diff --git a/app/src/main/java/agzam/vyatsu/data/local/DepartmentPeriodEntity.kt b/app/src/main/java/agzam/vyatsu/data/local/DepartmentPeriodEntity.kt
new file mode 100644
index 0000000..190a9b3
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/DepartmentPeriodEntity.kt
@@ -0,0 +1,28 @@
+package agzam.vyatsu.data.local
+
+import agzam.vyatsu.domain.model.Season
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+// Все опубликованные на сайте 2-недельные периоды кафедры, включая ещё не начавшиеся.
+@Entity(
+    tableName = "department_periods",
+    foreignKeys = [
+        ForeignKey(
+            entity = DepartmentEntity::class,
+            parentColumns = ["departmentId"],
+            childColumns = ["departmentId"],
+            onDelete = ForeignKey.CASCADE
+        )
+    ],
+    indices = [Index("departmentId")]
+)
+data class DepartmentPeriodEntity(
+    @PrimaryKey(autoGenerate = true) val id: Long = 0,
+    val departmentId: String,
+    val season: Season,
+    val weekStart: Long,
+    val weekEnd: Long
+)
diff --git a/app/src/main/java/agzam/vyatsu/data/local/PreferencesDao.kt b/app/src/main/java/agzam/vyatsu/data/local/PreferencesDao.kt
index 215baaa..3687422 100644
--- a/app/src/main/java/agzam/vyatsu/data/local/PreferencesDao.kt
+++ b/app/src/main/java/agzam/vyatsu/data/local/PreferencesDao.kt
@@ -28,6 +28,36 @@ interface PreferencesDao {
     @Query("INSERT OR REPLACE INTO preferences(key, value) VALUES('selectedDayDate', :date)")
     suspend fun setSelectedDayDate(date: String)
 
+    @Query("SELECT value FROM preferences WHERE key = 'selectedTeacherId'")
+    suspend fun selectedTeacherId(): String?
+
+    @Query(
+        "INSERT OR REPLACE INTO preferences(key, value) VALUES('selectedTeacherId', :teacherId)"
+    )
+    suspend fun setSelectedTeacherId(teacherId: String)
+
+    @Query("SELECT value FROM preferences WHERE key = 'selectedTeacherWeekStart'")
+    suspend fun selectedTeacherWeekStart(): String?
+
+    @Query(
+        "INSERT OR REPLACE INTO preferences(key, value) VALUES('selectedTeacherWeekStart', :weekStart)"
+    )
+    suspend fun setSelectedTeacherWeekStart(weekStart: String)
+
+    @Query("SELECT value FROM preferences WHERE key = 'selectedTeacherDayDate'")
+    suspend fun selectedTeacherDayDate(): String?
+
+    @Query(
+        "INSERT OR REPLACE INTO preferences(key, value) VALUES('selectedTeacherDayDate', :date)"
+    )
+    suspend fun setSelectedTeacherDayDate(date: String)
+
+    @Query(
+        "DELETE FROM preferences WHERE key IN " +
+            "('selectedTeacherId', 'selectedTeacherWeekStart', 'selectedTeacherDayDate')"
+    )
+    suspend fun clearSelectedTeacher()
+
     @Query("SELECT value FROM preferences WHERE key = 'autoUpdateEnabled'")
     suspend fun autoUpdateEnabled(): String?
 
diff --git a/app/src/main/java/agzam/vyatsu/data/local/TeacherDao.kt b/app/src/main/java/agzam/vyatsu/data/local/TeacherDao.kt
new file mode 100644
index 0000000..c92486a
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/TeacherDao.kt
@@ -0,0 +1,39 @@
+package agzam.vyatsu.data.local
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface TeacherDao {
+    @Query("SELECT * FROM departments ORDER BY name")
+    fun observeDepartments(): Flow<List<DepartmentEntity>>
+
+    @Query("SELECT * FROM departments WHERE departmentId = :id")
+    suspend fun getDepartment(id: String): DepartmentEntity?
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertAll(departments: List<DepartmentEntity>)
+
+    @Query("SELECT MAX(lastSyncedAt) FROM departments")
+    suspend fun maxSyncedAt(): Long?
+
+    @Query("SELECT DISTINCT faculty FROM departments ORDER BY faculty")
+    suspend fun getFaculties(): List<String>
+
+    @Query("DELETE FROM department_periods")
+    suspend fun deleteAllPeriods()
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertPeriods(periods: List<DepartmentPeriodEntity>)
+
+    @Query(
+        "SELECT * FROM department_periods WHERE weekStart <= :epochDay AND weekEnd >= :epochDay ORDER BY departmentId"
+    )
+    suspend fun getPeriodsForDate(epochDay: Long): List<DepartmentPeriodEntity>
+
+    @Query("SELECT * FROM department_periods WHERE departmentId = :departmentId ORDER BY weekStart")
+    suspend fun getPeriodsForDepartment(departmentId: String): List<DepartmentPeriodEntity>
+}
diff --git a/app/src/main/java/agzam/vyatsu/data/local/TeacherDayEntity.kt b/app/src/main/java/agzam/vyatsu/data/local/TeacherDayEntity.kt
new file mode 100644
index 0000000..c516b8a
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/TeacherDayEntity.kt
@@ -0,0 +1,27 @@
+package agzam.vyatsu.data.local
+
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+@Entity(
+    tableName = "teacher_days",
+    foreignKeys = [
+        ForeignKey(
+            entity = TeacherScheduleEntity::class,
+            parentColumns = ["id"],
+            childColumns = ["scheduleId"],
+            onDelete = ForeignKey.CASCADE
+        )
+    ],
+    indices = [
+        Index("scheduleId"),
+        Index("date")
+    ]
+)
+data class TeacherDayEntity(
+    @PrimaryKey(autoGenerate = true) val id: Long = 0,
+    val scheduleId: Long,
+    val date: Long
+)
diff --git a/app/src/main/java/agzam/vyatsu/data/local/TeacherLessonEntity.kt b/app/src/main/java/agzam/vyatsu/data/local/TeacherLessonEntity.kt
new file mode 100644
index 0000000..d84c905
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/TeacherLessonEntity.kt
@@ -0,0 +1,41 @@
+package agzam.vyatsu.data.local
+
+import agzam.vyatsu.domain.model.LessonType
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+@Entity(
+    tableName = "teacher_lessons",
+    foreignKeys = [
+        ForeignKey(
+            entity = TeacherDayEntity::class,
+            parentColumns = ["id"],
+            childColumns = ["dayId"],
+            onDelete = ForeignKey.CASCADE
+        )
+    ],
+    indices = [
+        Index("dayId"),
+        Index("teacher"),
+        Index("room"),
+        Index("subject")
+    ]
+)
+data class TeacherLessonEntity(
+    @PrimaryKey(autoGenerate = true) val id: Long = 0,
+    val dayId: Long,
+    val date: Long,
+    val slotIndex: Int,
+    val start: Int,
+    val end: Int,
+    val lessonIndex: Int,
+    val raw: String,
+    val room: String?,
+    val groupName: String?,
+    val subgroup: String?,
+    val subject: String?,
+    val type: LessonType,
+    val teacher: String
+)
diff --git a/app/src/main/java/agzam/vyatsu/data/local/TeacherScheduleDao.kt b/app/src/main/java/agzam/vyatsu/data/local/TeacherScheduleDao.kt
new file mode 100644
index 0000000..e995c8d
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/TeacherScheduleDao.kt
@@ -0,0 +1,66 @@
+package agzam.vyatsu.data.local
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface TeacherScheduleDao {
+
+    @Query("SELECT * FROM teacher_schedules ORDER BY weekStart DESC")
+    fun observeSchedules(): Flow<List<TeacherScheduleEntity>>
+
+    @Query("SELECT * FROM teacher_schedules ORDER BY weekStart DESC")
+    suspend fun getSchedules(): List<TeacherScheduleEntity>
+
+    @Query("DELETE FROM teacher_days WHERE scheduleId = :scheduleId")
+    suspend fun deleteDaysForSchedule(scheduleId: Long)
+
+    @Insert(onConflict = OnConflictStrategy.ABORT)
+    suspend fun insertSchedule(schedule: TeacherScheduleEntity): Long
+
+    @Query(
+        "DELETE FROM teacher_schedules WHERE departmentId = :departmentId AND season = :season AND weekStart = :weekStart"
+    )
+    suspend fun deleteSchedule(departmentId: String, season: String, weekStart: Long)
+
+    @Query("DELETE FROM teacher_schedules WHERE season = :season AND weekStart = :weekStart")
+    suspend fun deletePeriod(season: String, weekStart: Long)
+
+    @Query("DELETE FROM teacher_schedules")
+    suspend fun deleteAll()
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertDays(days: List<TeacherDayEntity>): List<Long>
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertLessons(lessons: List<TeacherLessonEntity>)
+
+    @Query(
+        "SELECT teacher_days.* FROM teacher_days INNER JOIN teacher_schedules ON teacher_schedules.id = teacher_days.scheduleId " +
+            "WHERE teacher_schedules.season = :season AND teacher_schedules.weekStart = :weekStart ORDER BY teacher_days.date"
+    )
+    fun observeDaysForPeriod(season: String, weekStart: Long): Flow<List<TeacherDayEntity>>
+
+    @Query(
+        "SELECT teacher_lessons.* FROM teacher_lessons INNER JOIN teacher_days ON teacher_days.id = teacher_lessons.dayId " +
+            "INNER JOIN teacher_schedules ON teacher_schedules.id = teacher_days.scheduleId " +
+            "WHERE teacher_schedules.season = :season AND teacher_schedules.weekStart = :weekStart " +
+            "ORDER BY teacher_lessons.date, teacher_lessons.slotIndex, teacher_lessons.lessonIndex"
+    )
+    fun observeLessonsForPeriod(season: String, weekStart: Long): Flow<List<TeacherLessonEntity>>
+
+    @Query(
+        "SELECT DISTINCT teacher FROM teacher_lessons INNER JOIN teacher_days ON teacher_days.id = teacher_lessons.dayId " +
+            "INNER JOIN teacher_schedules ON teacher_schedules.id = teacher_days.scheduleId " +
+            "WHERE teacher_schedules.season = :season AND teacher_schedules.weekStart = :weekStart ORDER BY teacher"
+    )
+    fun observeDistinctTeachers(season: String, weekStart: Long): Flow<List<String>>
+
+    @Query(
+        "SELECT EXISTS(SELECT 1 FROM teacher_schedules WHERE season = :season AND weekStart = :weekStart)"
+    )
+    suspend fun hasSchedulesForPeriod(season: String, weekStart: Long): Boolean
+}
diff --git a/app/src/main/java/agzam/vyatsu/data/local/TeacherScheduleEntity.kt b/app/src/main/java/agzam/vyatsu/data/local/TeacherScheduleEntity.kt
new file mode 100644
index 0000000..fcb57f2
--- /dev/null
+++ b/app/src/main/java/agzam/vyatsu/data/local/TeacherScheduleEntity.kt
@@ -0,0 +1,31 @@
+package agzam.vyatsu.data.local
+
+import agzam.vyatsu.domain.model.Season
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.Index
+import androidx.room.PrimaryKey
+
+@Entity(
+    tableName = "teacher_schedules",
+    foreignKeys = [
+        ForeignKey(
+            entity = DepartmentEntity::class,
+            parentColumns = ["departmentId"],
+            childColumns = ["departmentId"],
+            onDelete = ForeignKey.CASCADE
+        )
+    ],
+    indices = [
+        Index("departmentId"),
+        Index(value = ["departmentId", "season", "weekStart"], unique = true)
+    ]
+)
+data class TeacherScheduleEntity(
+    @PrimaryKey(autoGenerate = true) val id: Long = 0,
+    val departmentId: String,
+    val season: Season,
+    val weekStart: Long,
+    val weekEnd: Long,
+    val lastSyncedAt: Long
+)
diff --git a/app/src/main/java/agzam/vyatsu/data/repository/PreferencesRepositoryImpl.kt b/app/src/main/java/agzam/vyatsu/data/repository/PreferencesRepositoryImpl.kt
index a2cf860..d06b63f 100644
--- a/app/src/main/java/agzam/vyatsu/data/repository/PreferencesRepositoryImpl.kt
+++ b/app/src/main/java/agzam/vyatsu/data/repository/PreferencesRepositoryImpl.kt
@@ -14,6 +14,16 @@ class PreferencesRepositoryImpl(
     override suspend fun selectedDayDate(): String? = dao.selectedDayDate()
     override suspend fun setSelectedDayDate(date: String) = dao.setSelectedDayDate(date)
 
+    override suspend fun selectedTeacherId(): String? = dao.selectedTeacherId()
+    override suspend fun setSelectedTeacherId(id: String) = dao.setSelectedTeacherId(id)
+    override suspend fun selectedTeacherWeekStart(): String? = dao.selectedTeacherWeekStart()
+    override suspend fun setSelectedTeacherWeekStart(weekStart: String) =
+        dao.setSelectedTeacherWeekStart(weekStart)
+    override suspend fun selectedTeacherDayDate(): String? = dao.selectedTeacherDayDate()
+    override suspend fun setSelectedTeacherDayDate(date: String) =
+        dao.setSelectedTeacherDayDate(date)
+    override suspend fun clearSelectedTeacher() = dao.clearSelectedTeacher()
+
     override suspend fun autoUpdateEnabled(): Boolean = dao.autoUpdateEnabled() == "true"
     override suspend fun setAutoUpdateEnabled(enabled: Boolean) = dao.setAutoUpdateEnabled(enabled.toString())