Implemented api authentication. Removed old secret system

Moonlight.ApiServer/Services/ApiKeyService.cs

@@ -0,0 +1,56 @@
+using System.IdentityModel.Tokens.Jwt;
+using System.Text;
+using System.Text.Json;
+using Microsoft.IdentityModel.Tokens;
+using MoonCore.Attributes;
+using Moonlight.ApiServer.Configuration;
+using Moonlight.ApiServer.Database.Entities;
+
+namespace Moonlight.ApiServer.Services;
+
+[Singleton]
+public class ApiKeyService
+{
+    private readonly AppConfiguration Configuration;
+
+    public ApiKeyService(AppConfiguration configuration)
+    {
+        Configuration = configuration;
+    }
+
+    public string GenerateJwt(ApiKey apiKey)
+    {
+        var permissions = JsonSerializer.Deserialize<string[]>(apiKey.PermissionsJson) ?? [];
+        
+        var jwtSecurityTokenHandler = new JwtSecurityTokenHandler();
+
+        var descriptor = new SecurityTokenDescriptor()
+        {
+            Expires = apiKey.ExpiresAt,
+            IssuedAt = DateTime.Now,
+            NotBefore = DateTime.Now.AddMinutes(-1),
+            Claims = new Dictionary<string, object>()
+            {
+                {
+                    "apiKeyId",
+                    apiKey.Id
+                },
+                {
+                    "permissions",
+                    string.Join(";", permissions)
+                }
+            },
+            SigningCredentials = new SigningCredentials(
+                new SymmetricSecurityKey(
+                    Encoding.UTF8.GetBytes(Configuration.Authentication.Secret)
+                ),
+                SecurityAlgorithms.HmacSha256
+            ),
+            Issuer = Configuration.PublicUrl,
+            Audience = Configuration.PublicUrl
+        };
+
+        var securityToken = jwtSecurityTokenHandler.CreateJwtSecurityToken(descriptor);
+        return jwtSecurityTokenHandler.WriteToken(securityToken);
+    }
+}