Add .env integration

closes #105

Author: hazre

.gitignore

@@ -366,3 +366,9 @@ FodyWeavers.xsd
 
 # Rider config directory
 .idea/
+
+# Environment files
+*.env
+*.env.*
+!*.env.template
+!*.env.*.template

ThunderstoreCLI/Configuration/Config.cs

@@ -32,6 +32,11 @@ private Config()
     }
     public static Config FromCLI(IConfigProvider cliConfig)
     {
+        var environment = Environment.GetEnvironmentVariable("DOTNET_ENVIRONMENT")
+                          ?? Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT")
+                          ?? Environment.GetEnvironmentVariable("ENVIRONMENT");
+        DotEnv.LoadAll(environment);
+
         List<IConfigProvider> providers = new();
         providers.Add(cliConfig);
         providers.Add(new EnvironmentConfig());

ThunderstoreCLI/Configuration/DotEnv.cs

@@ -0,0 +1,55 @@
+namespace ThunderstoreCLI.Configuration;
+
+public static class DotEnv
+{
+    public static void Load(string filePath)
+    {
+        if (!File.Exists(filePath))
+            return;
+
+        foreach (var line in File.ReadAllLines(filePath))
+        {
+            if (string.IsNullOrWhiteSpace(line) || line.TrimStart().StartsWith('#'))
+                continue;
+
+            var parts = line.Split('=', 2);
+            if (parts.Length != 2)
+                continue;
+
+            var key = parts[0].Trim();
+            var value = parts[1].Trim();
+
+            if (value.Length >= 2)
+            {
+                if ((value.StartsWith('"') && value.EndsWith('"')) ||
+                    (value.StartsWith('\'') && value.EndsWith('\'')))
+                {
+                    value = value.Substring(1, value.Length - 2);
+                }
+            }
+
+            Environment.SetEnvironmentVariable(key, value);
+        }
+    }
+
+    public static void LoadAll(string? environment = null)
+    {
+        var filesToLoad = new List<string> { ".env" };
+
+        if (!string.IsNullOrEmpty(environment))
+        {
+            filesToLoad.Add($".env.{environment}");
+            filesToLoad.Add($".env.{environment.ToLowerInvariant()}");
+            filesToLoad.Add($".{environment}.env");
+            filesToLoad.Add($".{environment.ToLowerInvariant()}.env");
+        }
+
+        filesToLoad.Add(".env.local");
+        filesToLoad.Add(".local.env");
+
+        foreach (var file in filesToLoad)
+        {
+            Load(file);
+        }
+    }
+}