Add basic Golang CLI application

.gitignore

@@ -7,6 +7,7 @@
 *.dll
 *.so
 *.dylib
+agentmail
 
 # Test binary, built with `go test -c`
 *.test

CLAUDE.md

@@ -0,0 +1,87 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+AgentMail is a Golang CLI application built using the [Cobra](https://github.com/spf13/cobra) framework. The project follows the standard Cobra architectural pattern with a modular command structure.
+
+## Development Commands
+
+### Building
+```bash
+go build -o agentmail
+```
+
+### Testing
+```bash
+# Run all tests
+go test ./cmd/... -v
+
+# Run tests with coverage
+go test ./cmd/... -cover
+
+# Run a specific test
+go test ./cmd -v -run TestHelloCommand
+
+# Run a specific sub-test
+go test ./cmd -v -run TestHelloCommand/custom_name_with_--name
+```
+
+### Running the CLI
+```bash
+./agentmail --help
+./agentmail version
+./agentmail hello --name Alice
+```
+
+## Architecture
+
+### Command Structure
+
+The application uses Cobra's command registration pattern:
+
+1. **`main.go`** - Entry point that calls `cmd.Execute()`
+2. **`cmd/root.go`** - Defines the root command and `Execute()` function
+3. **`cmd/<command>.go`** - Individual command files that auto-register via `init()`
+
+### Adding a New Command
+
+To add a new command:
+
+1. Create `cmd/<commandname>.go`
+2. Define the command using `&cobra.Command{}`
+3. Register it in `init()` with `rootCmd.AddCommand(<commandname>Cmd)`
+4. Create corresponding `cmd/<commandname>_test.go` for tests
+
+Example pattern:
+```go
+var myCmd = &cobra.Command{
+    Use:   "mycommand",
+    Short: "Brief description",
+    Long:  "Detailed description",
+    Run: func(cmd *cobra.Command, args []string) {
+        // Command logic
+    },
+}
+
+func init() {
+    rootCmd.AddCommand(myCmd)
+    // Add flags with: myCmd.Flags().StringVarP(...)
+}
+```
+
+### Command Registration
+
+All commands in `cmd/` package are automatically registered through `init()` functions. The `init()` functions execute before `main()`, registering commands with `rootCmd` via `rootCmd.AddCommand()`.
+
+### Testing Pattern
+
+Tests create isolated Cobra command instances to avoid state pollution between tests. Each test constructs its own command tree and uses buffers to capture output for assertions.
+
+## Code Conventions
+
+- **Version**: Defined as a constant in `cmd/version.go`
+- **Flags**: Use `StringVarP()` for flags with both long (`--name`) and short (`-n`) forms
+- **Package-level vars**: Used for flag values (e.g., `var helloName string`)
+- **Module path**: `github.com/UserAd/AgentMail`

README.md

@@ -1 +1,47 @@
-# AgentMail
+# AgentMail
+
+A Golang CLI application built with [Cobra](https://github.com/spf13/cobra).
+
+## Installation
+
+```bash
+go build -o agentmail
+```
+
+## Usage
+
+```bash
+# Show help
+./agentmail help
+
+# Show version
+./agentmail version
+
+# Say hello
+./agentmail hello
+./agentmail hello --name Alice
+./agentmail hello -n Bob  # short flag
+```
+
+## Commands
+
+- `version` - Display version information
+- `hello` - Say hello with optional name flag (--name or -n)
+- `help` - Show usage information
+- `completion` - Generate shell autocompletion scripts
+
+## Development
+
+### Running Tests
+
+```bash
+# Run all tests
+go test ./cmd/... -v
+
+# Run with coverage
+go test ./cmd/... -cover
+```
+
+## Technology Stack
+
+- [Cobra](https://github.com/spf13/cobra) - Modern CLI framework for Go

cmd/hello.go

@@ -0,0 +1,23 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+var helloName string
+
+var helloCmd = &cobra.Command{
+	Use:   "hello",
+	Short: "Say hello to someone",
+	Long:  `Say hello to a person. You can specify a custom name using the --name flag.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Printf("Hello, %s!\n", helloName)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(helloCmd)
+	helloCmd.Flags().StringVarP(&helloName, "name", "n", "World", "Name to greet")
+}

cmd/hello_test.go

@@ -0,0 +1,68 @@
+package cmd
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"github.com/spf13/cobra"
+)
+
+func TestHelloCommand(t *testing.T) {
+	tests := []struct {
+		name     string
+		args     []string
+		want     string
+	}{
+		{
+			name: "default greeting",
+			args: []string{"hello"},
+			want: "Hello, World!",
+		},
+		{
+			name: "custom name with --name",
+			args: []string{"hello", "--name", "Alice"},
+			want: "Hello, Alice!",
+		},
+		{
+			name: "custom name with -n",
+			args: []string{"hello", "-n", "Bob"},
+			want: "Hello, Bob!",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Create a buffer to capture output
+			buf := new(bytes.Buffer)
+
+			// Create a new root command for testing
+			testRootCmd := &cobra.Command{Use: "agentmail"}
+			var testName string
+			testHelloCmd := &cobra.Command{
+				Use:   "hello",
+				Short: "Say hello",
+				Run: func(cmd *cobra.Command, args []string) {
+					buf.WriteString("Hello, " + testName + "!\n")
+				},
+			}
+			testHelloCmd.Flags().StringVarP(&testName, "name", "n", "World", "Name to greet")
+			testRootCmd.AddCommand(testHelloCmd)
+			testRootCmd.SetOut(buf)
+			testRootCmd.SetArgs(tt.args)
+
+			// Execute the command
+			err := testRootCmd.Execute()
+			if err != nil {
+				t.Fatalf("Unexpected error: %v", err)
+			}
+
+			// Check the output
+			got := strings.TrimSpace(buf.String())
+			want := tt.want
+			if got != want {
+				t.Errorf("got %q, want %q", got, want)
+			}
+		})
+	}
+}

cmd/root.go

@@ -0,0 +1,25 @@
+package cmd
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var rootCmd = &cobra.Command{
+	Use:   "agentmail",
+	Short: "AgentMail - A basic Golang CLI application",
+	Long:  `AgentMail is a CLI application built with Cobra for managing email operations.`,
+}
+
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func init() {
+	// Add global flags here if needed
+}

cmd/root_test.go

@@ -0,0 +1,29 @@
+package cmd
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestRootCommand(t *testing.T) {
+	// Create a buffer to capture output
+	buf := new(bytes.Buffer)
+
+	// Reset rootCmd for testing
+	testCmd := rootCmd
+	testCmd.SetOut(buf)
+	testCmd.SetErr(buf)
+	testCmd.SetArgs([]string{"--help"})
+
+	// Execute the command
+	err := testCmd.Execute()
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+
+	// Check the output contains expected text
+	got := buf.String()
+	if got == "" {
+		t.Error("Expected help output, got empty string")
+	}
+}

cmd/version.go

@@ -0,0 +1,27 @@
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+const version = "0.1.0"
+
+var versionCmd = &cobra.Command{
+	Use:   "version",
+	Short: "Print the version number of AgentMail",
+	Long:  `Display the current version of AgentMail CLI application.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		fmt.Printf("AgentMail version %s\n", version)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(versionCmd)
+}
+
+// GetVersion returns the current version
+func GetVersion() string {
+	return version
+}

cmd/version_test.go

@@ -0,0 +1,50 @@
+package cmd
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"github.com/spf13/cobra"
+)
+
+func TestVersionCommand(t *testing.T) {
+	// Create a buffer to capture output
+	buf := new(bytes.Buffer)
+
+	// Create a new root command for testing
+	testRootCmd := &cobra.Command{Use: "agentmail"}
+	testVersionCmd := &cobra.Command{
+		Use:   "version",
+		Short: "Print the version number",
+		Run: func(cmd *cobra.Command, args []string) {
+			buf.WriteString("AgentMail version " + GetVersion() + "\n")
+		},
+	}
+	testRootCmd.AddCommand(testVersionCmd)
+	testRootCmd.SetOut(buf)
+	testRootCmd.SetArgs([]string{"version"})
+
+	// Execute the command
+	err := testRootCmd.Execute()
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+
+	// Check the output
+	got := buf.String()
+	want := "AgentMail version " + version
+	if !strings.Contains(got, want) {
+		t.Errorf("got %q, want %q", got, want)
+	}
+}
+
+func TestGetVersion(t *testing.T) {
+	v := GetVersion()
+	if v == "" {
+		t.Error("GetVersion() returned empty string")
+	}
+	if v != version {
+		t.Errorf("GetVersion() = %q, want %q", v, version)
+	}
+}

go.mod

@@ -0,0 +1,9 @@
+module github.com/UserAd/AgentMail
+
+go 1.24.7
+
+require (
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/spf13/cobra v1.10.2 // indirect
+	github.com/spf13/pflag v1.0.9 // indirect
+)

go.sum

@@ -0,0 +1,10 @@
+github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/spf13/cobra v1.10.2 h1:DMTTonx5m65Ic0GOoRY2c16WCbHxOOw6xxezuLaBpcU=
+github.com/spf13/cobra v1.10.2/go.mod h1:7C1pvHqHw5A4vrJfjNwvOdzYu0Gml16OCs2GRiTUUS4=
+github.com/spf13/pflag v1.0.9 h1:9exaQaMOCwffKiiiYk6/BndUBv+iRViNW+4lEMi0PvY=
+github.com/spf13/pflag v1.0.9/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=