1 files changed, 79 insertions, 0 deletions

diff --git a/api/internal/controllers/auth.go b/api/internal/controllers/auth.go
new file mode 100644
index 0000000..ab2fbbb
--- /dev/null
+++ b/api/internal/controllers/auth.go
@@ -0,0 +1,79 @@
+package controllers
+
+import (
+        "crypto/rand"
+        "database/sql"
+        "encoding/base64"
+        "errors"
+        "github.com/gin-gonic/gin"
+        "net/http"
+        "water/api/internal/models"
+
+        _ "github.com/mattn/go-sqlite3"
+        "golang.org/x/crypto/bcrypt"
+        "water/api/internal/database"
+)
+
+
+
+// AuthHandler is a function that handles users' authentication. It checks if the request
+// has valid credentials, authenticates the user and sets the user's session.
+// If the authentication is successful, it will allow the user to access protected routes.
+func AuthHandler (c *gin.Context) {
+        username, password, ok := c.Request.BasicAuth()
+        if !ok {
+                c.Header("WWW-Authenticate", `Basic realm="Please enter your username and password."`)
+                c.AbortWithStatus(http.StatusUnauthorized)
+                return
+        }
+
+        db := database.EstablishDBConnection()
+        defer func(db *sql.DB) {
+                err := db.Close()
+                if err != nil {
+                        c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+                        return
+                }
+        }(db)
+
+        var user models.User
+        var preference models.Preference
+
+        row := db.QueryRow("SELECT id as 'id', name, uuid, password FROM Users WHERE name = ?", username)
+        if err := row.Scan(&user.ID, &user.Name, &user.UUID, &user.Password); err != nil {
+                if errors.Is(err, sql.ErrNoRows) {
+                        c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
+                        return
+                }
+        }
+
+        row = db.QueryRow("SELECT id, color, size_id, user_id FROM Preferences where user_id = ?", user.ID)
+        if err := row.Scan(&preference.ID, &preference.Color, &preference.SizeID, &preference.UserID); err != nil {
+                if errors.Is(err, sql.ErrNoRows) {
+                        c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
+                }
+        }
+
+        if err := bcrypt.CompareHashAndPassword([]byte(user.Password), []byte(password)); err != nil {
+                c.JSON(http.StatusUnauthorized, gin.H{"error": err.Error()})
+                return
+        }
+
+        // Generate a simple API token
+        apiToken := generateToken()
+        c.JSON(http.StatusOK, gin.H{"token": apiToken, "user": user, "preferences": preference})
+}
+
+
+// generateToken is a helper function used in the AuthHandler. It generates a random token for API authentication.
+// This function creates an empty byte slice of length 32 and fills it with cryptographic random data using the rand.Read function.
+// If an error occurs during the generation, it will return an empty string.
+// The generated cryptographic random data is then encoded into a base64 string and returned.
+func generateToken() string {
+        token := make([]byte, 32)
+        _, err := rand.Read(token)
+        if err != nil {
+                return ""
+        }
+        return base64.StdEncoding.EncodeToString(token)
+}
\ No newline at end of file