tsk-11: Added endpoint to get Contact (#17)

Closes #11

Reviewed-on: phoenix/textsender-api#17
Co-authored-by: phoenix <kundeng00@pm.me>
Co-committed-by: phoenix <kundeng00@pm.me>

internal/handler/contact.go

@@ -20,6 +20,11 @@ type AddContactResponse struct {
 	Data    []contact.Contact `json:"data"`
 }
 
+type GetContactResponse struct {
+	Message string            `json:"message"`
+	Data    []contact.Contact `json:"data"`
+}
+
 type ContactHandler struct {
 	ContactStore store.ContactStore
 }
@@ -70,3 +75,80 @@ func (c *ContactHandler) AddContact(w http.ResponseWriter, r *http.Request) {
 
 	RespondWithJSON(w, statusCode, &resp)
 }
+
+func (c *ContactHandler) GetContact(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		fmt.Println("Method:", r.Method)
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var id, userId uuid.UUID
+	queryParams := r.URL.Query()
+
+	// Check if parameter exists
+	if _, exists := queryParams["id"]; !exists {
+		if _, exists := queryParams["user_id"]; !exists {
+			fmt.Fprintf(w, "Name parameter not provided")
+			http.Error(w, "Query params", http.StatusBadRequest)
+			return
+		} else {
+			var err error
+			userId, err = uuid.Parse(queryParams.Get("user_id"))
+			if err != nil {
+				fmt.Fprintf(w, "Name parameter exists: %s", userId)
+			}
+		}
+	} else {
+		var err error
+		idTmp := queryParams.Get("id")
+		id, err = uuid.Parse(idTmp)
+		if err != nil {
+			fmt.Println("Error:", err)
+			http.Error(w, "Error parsing Id", http.StatusBadRequest)
+			return
+		}
+	}
+
+	var statusCode int
+	var resp GetContactResponse
+
+	ctx := r.Context()
+
+	if id != uuid.Nil {
+		fmt.Println("Checking with Id")
+		if con, err := c.ContactStore.GetContactByID(ctx, id); err == nil {
+			statusCode = http.StatusOK
+			resp.Message = "Successful"
+			resp.Data = append(resp.Data, *con)
+		} else {
+			statusCode = http.StatusInternalServerError
+			resp.Message = err.Error()
+		}
+	} else if userId != uuid.Nil {
+		fmt.Println("Checking with User Id")
+		if contacts, err := c.ContactStore.GetAllContacts(ctx); err == nil {
+			for _, con := range contacts {
+				if con.UserId == userId {
+					resp.Data = append(resp.Data, *con)
+				}
+			}
+
+			if len(resp.Data) > 0 {
+				statusCode = http.StatusOK
+				resp.Message = "Successful"
+			} else {
+				statusCode = http.StatusNotFound
+				resp.Message = "Contact not found"
+			}
+		} else {
+			statusCode = http.StatusInternalServerError
+			resp.Message = err.Error()
+		}
+	} else {
+		statusCode = http.StatusBadRequest
+		resp.Message = "Invalid query parameter"
+	}
+
+	RespondWithJSON(w, statusCode, &resp)
+}