1 files changed, 272 insertions, 0 deletions
diff --git a/backend/internal/api/handlers/goal_handler.go b/backend/internal/api/handlers/goal_handler.go
new file mode 100644
index 0000000..09bea74
--- /dev/null
+++ b/backend/internal/api/handlers/goal_handler.go
@@ -0,0 +1,272 @@
+package handlers
+
+import (
+	"log"
+	"net/http"
+	"strconv"
+	"time"
+
+	"finance/backend/internal/database"
+	"finance/backend/internal/models"
+
+	"github.com/gin-gonic/gin"
+)
+
+// CreateGoalInput defines the structure for creating a new financial goal
+type CreateGoalInput struct {
+	Name          string `json:"name" binding:"required"`
+	TargetAmount  int64  `json:"targetAmount" binding:"required"`
+	CurrentAmount int64  `json:"currentAmount"`
+	TargetDate    string `json:"targetDate"` // YYYY-MM-DD format
+	Status        string `json:"status"`
+}
+
+// UpdateGoalInput defines the structure for updating an existing financial goal
+type UpdateGoalInput struct {
+	Name          string `json:"name"`
+	TargetAmount  int64  `json:"targetAmount"`
+	CurrentAmount int64  `json:"currentAmount"`
+	TargetDate    string `json:"targetDate"` // YYYY-MM-DD format
+	Status        string `json:"status"`
+}
+
+// UpdateGoalProgressInput defines the structure for updating just the progress of a goal
+type UpdateGoalProgressInput struct {
+	CurrentAmount int64 `json:"currentAmount" binding:"required"`
+}
+
+// GoalHandler handles all goal-related operations in the API
+type GoalHandler struct {
+}
+
+// NewGoalHandler creates and returns a new GoalHandler instance
+func NewGoalHandler() *GoalHandler {
+	return &GoalHandler{}
+}
+
+// GetGoals retrieves all goals for the authenticated user
+// Optionally filtered by status if provided as a query parameter
+func (h *GoalHandler) GetGoals(c *gin.Context) {
+	userID := c.MustGet("userID").(uint)
+	var goals []models.Goal
+
+	query := database.DB.Where("user_id = ?", userID)
+
+	// Filter by status if provided
+	status := c.Query("status")
+	if status != "" {
+		query = query.Where("status = ?", status)
+	}
+
+	if err := query.Find(&goals).Error; err != nil {
+		log.Printf("Error fetching goals for user %d: %v", userID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to get goals"})
+		return
+	}
+
+	c.JSON(http.StatusOK, goals)
+}
+
+// GetGoal retrieves a specific goal by ID for the authenticated user
+func (h *GoalHandler) GetGoal(c *gin.Context) {
+	userID := c.MustGet("userID").(uint)
+	goalID, err := strconv.ParseUint(c.Param("id"), 10, 32)
+	if err != nil {
+		log.Printf("Error parsing goal ID: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid goal ID"})
+		return
+	}
+
+	var goal models.Goal
+	if err := database.DB.Where("id = ? AND user_id = ?", goalID, userID).First(&goal).Error; err != nil {
+		log.Printf("Error fetching goal ID %d for user %d: %v", goalID, userID, err)
+		c.JSON(http.StatusNotFound, gin.H{"error": "Goal not found"})
+		return
+	}
+
+	c.JSON(http.StatusOK, goal)
+}
+
+// CreateGoal creates a new financial goal for the authenticated user
+func (h *GoalHandler) CreateGoal(c *gin.Context) {
+	userID := c.MustGet("userID").(uint)
+	var input CreateGoalInput
+
+	if err := c.ShouldBindJSON(&input); err != nil {
+		log.Printf("Error binding JSON for goal creation: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// Set default status if not provided
+	status := "Active"
+	if input.Status != "" {
+		status = input.Status
+	}
+
+	// Parse target date if provided
+	var targetDate time.Time
+	if input.TargetDate != "" {
+		parsedDate, err := time.Parse("2006-01-02", input.TargetDate)
+		if err != nil {
+			log.Printf("Error parsing target date for goal creation: %v", err)
+			c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid date format for targetDate. Use YYYY-MM-DD"})
+			return
+		}
+		targetDate = parsedDate
+	}
+
+	goal := models.Goal{
+		UserID:        userID,
+		Name:          input.Name,
+		TargetAmount:  input.TargetAmount,
+		CurrentAmount: input.CurrentAmount,
+		Status:        status,
+	}
+
+	// Only set target date if it was provided
+	if !targetDate.IsZero() {
+		goal.TargetDate = targetDate
+	}
+
+	if err := database.DB.Create(&goal).Error; err != nil {
+		log.Printf("Error creating goal for user %d: %v", userID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create goal"})
+		return
+	}
+
+	log.Printf("Goal created successfully for user %d: %s (ID: %d)", userID, goal.Name, goal.ID)
+	c.JSON(http.StatusCreated, goal)
+}
+
+// UpdateGoal updates an existing goal for the authenticated user
+func (h *GoalHandler) UpdateGoal(c *gin.Context) {
+	userID := c.MustGet("userID").(uint)
+	goalID, err := strconv.ParseUint(c.Param("id"), 10, 32)
+	if err != nil {
+		log.Printf("Error parsing goal ID for update: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid goal ID"})
+		return
+	}
+
+	var goal models.Goal
+	if err := database.DB.Where("id = ? AND user_id = ?", goalID, userID).First(&goal).Error; err != nil {
+		log.Printf("Error fetching goal ID %d for user %d in update: %v", goalID, userID, err)
+		c.JSON(http.StatusNotFound, gin.H{"error": "Goal not found"})
+		return
+	}
+
+	var input UpdateGoalInput
+	if err := c.ShouldBindJSON(&input); err != nil {
+		log.Printf("Error binding JSON for goal update: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	// Update fields that were provided
+	if input.Name != "" {
+		goal.Name = input.Name
+	}
+	if input.TargetAmount != 0 {
+		goal.TargetAmount = input.TargetAmount
+	}
+	if input.CurrentAmount != 0 {
+		goal.CurrentAmount = input.CurrentAmount
+	}
+	if input.TargetDate != "" {
+		parsedDate, err := time.Parse("2006-01-02", input.TargetDate)
+		if err != nil {
+			log.Printf("Error parsing target date for goal update: %v", err)
+			c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid date format for targetDate. Use YYYY-MM-DD"})
+			return
+		}
+		goal.TargetDate = parsedDate
+	}
+	if input.Status != "" {
+		goal.Status = input.Status
+	}
+
+	// Check if goal has been achieved
+	if goal.CurrentAmount >= goal.TargetAmount {
+		goal.Status = "Achieved"
+		log.Printf("Goal ID %d for user %d automatically marked as Achieved", goalID, userID)
+	}
+
+	if err := database.DB.Save(&goal).Error; err != nil {
+		log.Printf("Error saving updated goal ID %d for user %d: %v", goalID, userID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to update goal"})
+		return
+	}
+
+	log.Printf("Goal ID %d updated successfully for user %d", goalID, userID)
+	c.JSON(http.StatusOK, goal)
+}
+
+// UpdateGoalProgress updates just the progress (current amount) of a goal
+func (h *GoalHandler) UpdateGoalProgress(c *gin.Context) {
+	userID := c.MustGet("userID").(uint)
+	goalID, err := strconv.ParseUint(c.Param("id"), 10, 32)
+	if err != nil {
+		log.Printf("Error parsing goal ID for progress update: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid goal ID"})
+		return
+	}
+
+	var goal models.Goal
+	if err := database.DB.Where("id = ? AND user_id = ?", goalID, userID).First(&goal).Error; err != nil {
+		log.Printf("Error fetching goal ID %d for user %d in progress update: %v", goalID, userID, err)
+		c.JSON(http.StatusNotFound, gin.H{"error": "Goal not found"})
+		return
+	}
+
+	var input UpdateGoalProgressInput
+	if err := c.ShouldBindJSON(&input); err != nil {
+		log.Printf("Error binding JSON for goal progress update: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	goal.CurrentAmount = input.CurrentAmount
+
+	// Check if goal has been achieved
+	if goal.CurrentAmount >= goal.TargetAmount {
+		goal.Status = "Achieved"
+		log.Printf("Goal ID %d for user %d automatically marked as Achieved during progress update", goalID, userID)
+	}
+
+	if err := database.DB.Save(&goal).Error; err != nil {
+		log.Printf("Error saving progress update for goal ID %d for user %d: %v", goalID, userID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to update goal progress"})
+		return
+	}
+
+	log.Printf("Goal ID %d progress updated successfully for user %d: %d/%d", goalID, userID, goal.CurrentAmount, goal.TargetAmount)
+	c.JSON(http.StatusOK, goal)
+}
+
+// DeleteGoal deletes a goal belonging to the authenticated user
+func (h *GoalHandler) DeleteGoal(c *gin.Context) {
+	userID := c.MustGet("userID").(uint)
+	goalID, err := strconv.ParseUint(c.Param("id"), 10, 32)
+	if err != nil {
+		log.Printf("Error parsing goal ID for deletion: %v", err)
+		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid goal ID"})
+		return
+	}
+
+	var goal models.Goal
+	if err := database.DB.Where("id = ? AND user_id = ?", goalID, userID).First(&goal).Error; err != nil {
+		log.Printf("Error fetching goal ID %d for user %d for deletion: %v", goalID, userID, err)
+		c.JSON(http.StatusNotFound, gin.H{"error": "Goal not found"})
+		return
+	}
+
+	if err := database.DB.Delete(&goal).Error; err != nil {
+		log.Printf("Error deleting goal ID %d for user %d: %v", goalID, userID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to delete goal"})
+		return
+	}
+
+	log.Printf("Goal ID %d deleted successfully for user %d", goalID, userID)
+	c.JSON(http.StatusOK, gin.H{"message": "Goal deleted successfully"})
+}