Frontend mobile

API/dependencies/di.py

@@ -61,6 +61,9 @@ def get_expense_service(
 def get_group_service(repo: IGroupRepository = Depends(get_group_repository)) -> IGroupService:
     return GroupService(repo)
 
+def get_group_log_repository(db: Session = Depends(get_db)) -> IGroupLogRepository:
+    return GroupLogRepository(db)
+
 def get_user_group_service(
     user_group_repo: IUserGroupRepository = Depends(get_user_group_repository),
     group_repo: IGroupRepository = Depends(get_group_repository),
@@ -75,6 +78,17 @@ def get_group_log_service(
 ) -> IGroupLogService:
     return GroupLogService(group_log_repo, group_repo, user_repo)
 
+def get_user_group_service(
+    user_group_repo: IUserGroupRepository = Depends(get_user_group_repository),
+    group_repo: IGroupRepository = Depends(get_group_repository),
+    user_repo: IUserRepository = Depends(get_user_repository),
+    log_repo: IGroupLogRepository = Depends(get_group_log_repository),
+) -> IUserGroupService:
+    return UserGroupService(user_group_repo, group_repo, user_repo, log_repo)
+
+def get_expense_payment_repository(db: Session = Depends(get_db)) -> IExpensePaymentRepository:
+    return ExpensePaymentRepository(db)
+
 def get_expense_payment_service(
     repo: IExpensePaymentRepository = Depends(get_expense_payment_repository),
     expense_repository: IExpenseRepository = Depends(get_expense_repository),

API/repositories/category_repository.py

@@ -13,9 +13,6 @@ def add(self, category: Category) -> int: ...
     @abstractmethod
     def get_all(self, sort_by: str, order: str) -> List[Category]: ...
 
-    @abstractmethod
-    def get_by_id(self, category_id: int) -> Category: ...
-
     @abstractmethod
     def update(self, category_id: int, fields: dict) -> int: ...
 
@@ -33,7 +30,9 @@ def add(self, category: Category) -> int:
         return category.id
 
     def get_by_title_or_keywords(self, user_id: int, title: str, keywords: list[str]) -> bool:
-        statement = (select(Category.id).where(Category.user_id == user_id,or_(
+        statement = (select(Category.id).where(
+                Category.user_id == user_id,
+                or_(
                     Category.title == title,
                     Category.keywords.op("&&")(cast(keywords, ARRAY(Text))))))
         return self.db.scalar(statement) is not None

API/routes/category_routes.py

@@ -32,7 +32,7 @@ def get_all_categories(
 def update_category(category_id: int, category_in: CategoryUpdate, requester_id: int = Depends(get_current_user_id), category_service: ICategoryService = Depends(get_category_service)):
     return category_service.update_category(category_id, category_in, requester_id)
 
-@router.delete("/{category_id")
+@router.delete("/{category_id}")
 def delete_category(category_id: int, requester_id: int = Depends(get_current_user_id), category_service: ICategoryService = Depends(get_category_service)):
     return category_service.delete_category(category_id, requester_id)
 

API/routes/user_routes.py

@@ -57,7 +57,11 @@ def delete_user(user_id: int, _ = Depends(get_current_user_id), user_service: IU
 
 
 @router.post("/join-group/{invitation_code}")
-def join_group_with_invitation_code(invitation_code: str, user_id: int = Depends(get_current_user_id), user_group_service: IUserGroupService = Depends(get_user_group_service)):
+def join_group_with_invitation_code(
+    invitation_code: str, 
+    user_id: int = Depends(get_current_user_id), 
+    user_group_service: IUserGroupService = Depends(get_user_group_service)
+):
     """
     Allows the authenticated user to join a group using an invitation code.
     """

API/services/expense_service.py

@@ -127,7 +127,7 @@ def create_expense(self, data: ExpenseCreate, user_id: int) -> APIResponse:
         if data.group_id is not None:
             self._validate_group(data.group_id)
         self._validate_category(data.category_id, user_id)
-        
+
         id = self.repository.add(expense)
 
         return APIResponse(
@@ -181,11 +181,10 @@ def get_group_expenses(self, group_id: int, *args, **kwargs) -> APIResponse:
         Method for returning group expenses
         """
         self._validate_group(group_id)
-
         expenses = self.repository.get_by_group(group_id, *args, **kwargs)
 
         expenses_response = [ExpenseResponse.model_validate(expense) for expense in expenses]
-        
+
         return APIResponse(
             success=True,
             data=expenses_response
@@ -197,7 +196,7 @@ def update_expense(self, expense_id: int, data: ExpenseUpdate, requester_id: int
         """
         self._validate_owner(expense_id, requester_id)
         self._validate_category(data.category_id, requester_id)
-        
+
         fields = data.model_dump(exclude_unset=True)
         fields.pop("user_id", None)
 

API/services/group_service.py

@@ -9,6 +9,7 @@
 from schemas.group import GroupCreate, GroupResponse, GroupUpdate
 from utils.helpers.constants import ID_FIELD, STATUS_BAD_REQUEST, STATUS_NOT_FOUND
 from utils.helpers.generate_invitation_code import generate_invitation_code
+import base64
 
 
 class IGroupService(ABC):
@@ -153,7 +154,10 @@ def generate_invite_qr(self, group_id: int) -> APIResponse:
         img.save(buffer, format="PNG")
         buffer.seek(0)
 
+        # fastapi is throwing error when returning bytes directly, so encode it to base64
+        b64_bytes = base64.b64encode(buffer.read()).decode("utf-8")
+
         return APIResponse(
             success=True,
-            data=buffer.read(),
+            data=b64_bytes
         )

API/services/user_group_service.py

@@ -7,6 +7,7 @@
 from repositories.group_repository import IGroupRepository
 from repositories.user_group_repository import IUserGroupRepository
 from repositories.user_repository import IUserRepository
+from repositories.group_log_repository import IGroupLogRepository
 from schemas.api_response import APIResponse
 from schemas.group import GroupResponse
 from schemas.user import UserResponse
@@ -53,6 +54,7 @@ def __init__(
         repository: IUserGroupRepository,
         group_repo: IGroupRepository,
         user_repo: IUserRepository,
+        log_repo: IGroupLogRepository,
     ):
         """
         Constructor method.
@@ -61,6 +63,7 @@ def __init__(
         self.group_repo = group_repo
         self.user_repo = user_repo
         self.logger = Logger()
+        self.log_repo = log_repo
 
     def _validate_group(self, group_id: int = None, invitation_code: str = None) -> Group:
         if group_id is not None:
@@ -128,9 +131,17 @@ def add_user_to_group_by_invitation_code(self, user_id: int, invitation_code: st
             )
 
         response = self.repository.add_user_to_group_by_invitation_code(user_id, invitation_code)
-
-        group_id = response[0]
-        user_id = response[1]
+
+        group_response = GroupResponse.model_validate(response[0])
+        user_response = UserResponse.model_validate(response[1])
+
+        # log the join event
+        if self.log_repo:
+            self.log_repo.add(
+                group_id=group.id,
+                user_id=user_id,
+                action="JOIN"
+            )
 
         return APIResponse(
             success=True,

API/utils/helpers/constants.py

@@ -16,8 +16,8 @@
 
 
 # Fields for group statistics 
-TOTAL_GROUP_SPEND = "total_group_spend"
-MY_TOTAL_PAID = "my_total_paid"
-MY_SHARE_OF_EXPENSES = "my_share_of_expenses"
-NET_BALANCE_PAID_FOR_OTHERS = "net_balance_paid_for_others"
-REST_OF_GROUP_EXPENSES = "rest_of_group_expenses"
+TOTAL_GROUP_SPEND="total_group_spend"
+MY_TOTAL_PAID="my_total_paid"
+MY_SHARE_OF_EXPENSES="my_share_of_expenses"
+NET_BALANCE_PAID_FOR_OTHERS="net_balance_paid_for_others"
+REST_OF_GROUP_EXPENSES="rest_of_group_expenses"

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/BudgetResponse.kt

@@ -0,0 +1,14 @@
+package com.example.budgeting.android.data.model
+
+import com.squareup.moshi.Json
+
+class BudgetResponse(
+    @Json(name = "budget")
+    val budget: Double,
+
+    @Json(name = "spent_this_month")
+    val spentThisMonth: Double,
+
+    @Json(name = "remaining_budget")
+    val remainingBudget: Double
+)

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/Category.kt

@@ -0,0 +1,40 @@
+package com.example.budgeting.android.data.model
+
+import com.squareup.moshi.Json
+
+data class Category(
+    @Json(name = "id")
+    val id: Int,
+
+    @Json(name = "user_id")
+    val user_id: Int,
+
+    @Json(name = "title")
+    val title: String,
+
+    @Json(name = "keywords")
+    val keywords: List<String> = emptyList()
+)
+
+/**
+ * Request model for creating categories
+ */
+data class CategoryCreateRequest(
+    @Json(name = "title")
+    val title: String,
+
+    @Json(name = "keywords")
+    val keywords: List<String> = emptyList()
+)
+
+/**
+ * Request model for updating categories
+ */
+data class CategoryUpdateRequest(
+    @Json(name = "title")
+    val title: String? = null,
+
+    @Json(name = "keywords")
+    val keywords: List<String>? = null
+)
+

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/CategoryBody.kt

@@ -0,0 +1,6 @@
+package com.example.budgeting.android.data.model
+
+data class CategoryBody(
+    val title: String? = null,
+    val keywords: List<String>? = null
+)

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/Expense.kt

@@ -2,15 +2,6 @@ package com.example.budgeting.android.data.model
 
 import com.squareup.moshi.Json
 
-/**
- * Expense model matching the backend schema.
- * Backend schema: id (int, required), user_id (int?, optional), group_id (int?, optional),
- * title (str, required), category (str, required), amount (float, required), created_at (datetime, required)
- * 
- * Note: id and created_at are nullable to support creating new expenses (they're generated by backend),
- * but when receiving from backend, they should always be present. However, we make them nullable
- * to handle cases where the backend might return malformed data.
- */
 data class Expense(
     @Json(name = "id")
     val id: Int? = null,
@@ -23,18 +14,38 @@ data class Expense(
 
     @Json(name = "title")
     val title: String,
-    
-    @Json(name = "category")
-    val category: String,
-    
+
+    @Json(name = "category_id")
+    val categoryId: Int? = null,
+
     @Json(name = "amount")
     val amount: Double,
 
+    @Json(name = "description")
+    val description: String? = null,
+
     @Json(name = "created_at")
     val created_at: String? = null
 )
 
 data class ExpenseIdResponse(
     @Json(name = "id")
     val id: Int
+)
+
+data class ExpenseCreateRequest(
+    @Json(name = "title")
+    val title: String,
+
+    @Json(name = "amount")
+    val amount: Double,
+
+    @Json(name = "category_id")
+    val category_id: Int,
+
+    @Json(name = "group_id")
+    val group_id: Int? = null,
+
+    @Json(name = "description")
+    val description: String? = null
 )

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/ExpensePayment.kt

@@ -0,0 +1,15 @@
+package com.example.budgeting.android.data.model
+
+import com.squareup.moshi.Json
+
+data class ExpensePayment(
+    @Json(name = "expense_id")
+    val expense_id: Int,
+
+    @Json(name = "user_id")
+    val user_id: Int,
+
+    @Json(name = "paid_at")
+    val paid_at: String? = null
+)
+

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/GroupLog.kt

@@ -0,0 +1,21 @@
+package com.example.budgeting.android.data.model
+
+import com.squareup.moshi.Json
+
+data class GroupLog(
+    @Json(name = "id")
+    val id: Int,
+
+    @Json(name = "group_id")
+    val group_id: Int,
+
+    @Json(name = "user_id")
+    val user_id: Int,
+
+    @Json(name = "action")
+    val action: String, // "JOIN" or "LEAVE"
+
+    @Json(name = "created_at")
+    val created_at: String
+)
+

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/model/GroupResponseModels.kt

@@ -0,0 +1,23 @@
+package com.example.budgeting.android.data.model
+
+import com.squareup.moshi.Json
+
+data class GroupIdResponse(
+    @Json(name = "id")
+    val id: Int
+)
+
+data class AddUserToGroupResponse(
+    @Json(name = "group")
+    val group: Int,
+    @Json(name = "user")
+    val user: Int
+)
+
+data class JoinGroupResponse(
+    @Json(name = "group")
+    val group: Group,
+    @Json(name = "user")
+    val user: UserData
+)
+

Mobile/androidApp/src/main/java/com/example/budgeting/android/data/network/CategoryApiService.kt

@@ -0,0 +1,25 @@
+package com.example.budgeting.android.data.network
+
+import com.example.budgeting.android.data.model.ApiResponse
+import com.example.budgeting.android.data.model.Category
+import com.example.budgeting.android.data.model.CategoryBody
+import retrofit2.Response
+import retrofit2.http.*
+
+interface CategoryApiService {
+    @GET("/categories")
+    suspend fun getCategories(
+        @Query("sort_by") sortBy: String? = null,
+        @Query("order") order: String? = null
+    ): Response<ApiResponse<List<Category>>>
+
+    @POST("/categories")
+    suspend fun addCategory(@Body category: CategoryBody): Response<Unit>
+
+    @PUT("/categories/{id}")
+    suspend fun updateCategory(@Path("id") id: Int, @Body category: CategoryBody): Response<Unit>
+
+    @DELETE("/categories/{id}")
+    suspend fun deleteCategory(@Path("id") id: Int): Response<Unit>
+
+}