Initialize AutoLibrary website with Gitea deployment

backend/handlers/errors_handler/handler.go

@@ -0,0 +1,45 @@
+package errors_handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+)
+
+// 404 - Not Found
+func GetNotFoundError(c *gin.Context) {
+	errorData := gin.H{
+		"code": http.StatusNotFound,
+		"msg":  c.Request.Method + " > the requested API endpoint was not found",
+		"data": gin.H{
+			"path":   c.Request.URL.Path,
+			"method": c.Request.Method,
+			"endpoints": gin.H{
+				"health":    "/health",
+				"downloads": "/download/versions",
+			},
+		},
+	}
+
+	acceptHeader := c.GetHeader("Accept")
+	if strings.Contains(acceptHeader, "text/html") {
+		// for browser requests, return HTML
+		jsonBytes, err := json.Marshal(errorData)
+		if err != nil {
+			jsonBytes = []byte(`{"error": "json_serialization_failed"}`)
+		}
+		jsonStr := string(jsonBytes)
+		c.HTML(http.StatusNotFound, "404.html", gin.H{
+			"title":    "404 - Not Found",
+			"path":     c.Request.URL.Path,
+			"method":   c.Request.Method,
+			"baseURL":  c.Request.Host,
+			"jsonData": jsonStr,
+		})
+		return
+	}
+	// for General requests (no text/html in Accept header), return JSON
+	c.JSON(http.StatusNotFound, errorData)
+}