Implement internal mail skill MVP

internal/config/config.go

@@ -0,0 +1,177 @@
+package config
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type Config struct {
+	AccountID string
+	POP3      POP3Config
+	SMTP      SMTPConfig
+	Data      DataConfig
+	HTTP      HTTPConfig
+}
+
+type POP3Config struct {
+	Host           string
+	Port           int
+	Username       string
+	Password       string
+	UseTLS         bool
+	TimeoutSeconds int
+}
+
+type SMTPConfig struct {
+	Host              string
+	Port              int
+	Username          string
+	Password          string
+	UseTLS            bool
+	UseSTARTTLS       bool
+	AuthRequired      bool
+	AllowInsecureAuth bool
+	FromAddress       string
+	FromName          string
+	TimeoutSeconds    int
+}
+
+type DataConfig struct {
+	DataDir       string
+	DatabasePath  string
+	RawMailDir    string
+	AttachmentDir string
+}
+
+type HTTPConfig struct {
+	Host string
+	Port int
+}
+
+func (c POP3Config) Timeout() time.Duration {
+	return time.Duration(c.TimeoutSeconds) * time.Second
+}
+
+func (c SMTPConfig) Timeout() time.Duration {
+	return time.Duration(c.TimeoutSeconds) * time.Second
+}
+
+func Load(envPath string) (*Config, error) {
+	values := map[string]string{}
+	if envPath == "" {
+		envPath = ".env"
+	}
+	if err := readEnvFile(envPath, values); err != nil {
+		return nil, err
+	}
+	for _, item := range os.Environ() {
+		key, val, ok := strings.Cut(item, "=")
+		if ok {
+			values[key] = val
+		}
+	}
+
+	dataDir := getString(values, "DATA_DIR", "./data")
+	cfg := &Config{
+		AccountID: getString(values, "MAIL_ACCOUNT_ID", "default"),
+		POP3: POP3Config{
+			Host:           getString(values, "POP3_HOST", ""),
+			Port:           getInt(values, "POP3_PORT", 110),
+			Username:       getString(values, "POP3_USERNAME", ""),
+			Password:       getString(values, "POP3_PASSWORD", ""),
+			UseTLS:         getBool(values, "POP3_USE_TLS", false),
+			TimeoutSeconds: getInt(values, "POP3_TIMEOUT_SECONDS", 30),
+		},
+		SMTP: SMTPConfig{
+			Host:              getString(values, "SMTP_HOST", ""),
+			Port:              getInt(values, "SMTP_PORT", 25),
+			Username:          getString(values, "SMTP_USERNAME", ""),
+			Password:          getString(values, "SMTP_PASSWORD", ""),
+			UseTLS:            getBool(values, "SMTP_USE_TLS", false),
+			UseSTARTTLS:       getBool(values, "SMTP_USE_STARTTLS", false),
+			AuthRequired:      getBool(values, "SMTP_AUTH_REQUIRED", false),
+			AllowInsecureAuth: getBool(values, "SMTP_ALLOW_INSECURE_AUTH", false),
+			FromAddress:       getString(values, "SMTP_FROM_ADDRESS", ""),
+			FromName:          getString(values, "SMTP_FROM_NAME", ""),
+			TimeoutSeconds:    getInt(values, "SMTP_TIMEOUT_SECONDS", 30),
+		},
+		Data: DataConfig{
+			DataDir:       dataDir,
+			DatabasePath:  getString(values, "DATABASE_PATH", filepath.Join(dataDir, "internal_mail.db")),
+			RawMailDir:    getString(values, "RAW_MAIL_DIR", filepath.Join(dataDir, "raw")),
+			AttachmentDir: getString(values, "ATTACHMENT_DIR", filepath.Join(dataDir, "attachments")),
+		},
+		HTTP: HTTPConfig{
+			Host: getString(values, "HTTP_HOST", "127.0.0.1"),
+			Port: getInt(values, "HTTP_PORT", 8765),
+		},
+	}
+	return cfg, nil
+}
+
+func readEnvFile(path string, values map[string]string) error {
+	file, err := os.Open(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		return fmt.Errorf("read env file: %w", err)
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if line == "" || strings.HasPrefix(line, "#") {
+			continue
+		}
+		key, value, ok := strings.Cut(line, "=")
+		if !ok {
+			continue
+		}
+		key = strings.TrimSpace(key)
+		value = strings.TrimSpace(value)
+		value = strings.Trim(value, `"'`)
+		values[key] = value
+	}
+	return scanner.Err()
+}
+
+func getString(values map[string]string, key, def string) string {
+	if v, ok := values[key]; ok {
+		return v
+	}
+	return def
+}
+
+func getInt(values map[string]string, key string, def int) int {
+	v, ok := values[key]
+	if !ok || strings.TrimSpace(v) == "" {
+		return def
+	}
+	n, err := strconv.Atoi(v)
+	if err != nil {
+		return def
+	}
+	return n
+}
+
+func getBool(values map[string]string, key string, def bool) bool {
+	v, ok := values[key]
+	if !ok || strings.TrimSpace(v) == "" {
+		return def
+	}
+	switch strings.ToLower(strings.TrimSpace(v)) {
+	case "1", "true", "yes", "y", "on":
+		return true
+	case "0", "false", "no", "n", "off":
+		return false
+	default:
+		return def
+	}
+}

internal/config/config_test.go

@@ -0,0 +1,42 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestLoadDefaultsAndEnvFile(t *testing.T) {
+	dir := t.TempDir()
+	envPath := filepath.Join(dir, ".env")
+	if err := os.WriteFile(envPath, []byte("POP3_HOST=mail.local\nSMTP_PORT=2525\nSMTP_AUTH_REQUIRED=true\nSMTP_ALLOW_INSECURE_AUTH=true\nDATA_DIR="+dir+"\n"), 0600); err != nil {
+		t.Fatal(err)
+	}
+
+	cfg, err := Load(envPath)
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+
+	if cfg.AccountID != "default" {
+		t.Fatalf("AccountID = %q, want default", cfg.AccountID)
+	}
+	if cfg.POP3.Host != "mail.local" {
+		t.Fatalf("POP3.Host = %q", cfg.POP3.Host)
+	}
+	if cfg.POP3.Port != 110 {
+		t.Fatalf("POP3.Port = %d, want 110", cfg.POP3.Port)
+	}
+	if cfg.SMTP.Port != 2525 {
+		t.Fatalf("SMTP.Port = %d, want 2525", cfg.SMTP.Port)
+	}
+	if !cfg.SMTP.AuthRequired {
+		t.Fatal("SMTP.AuthRequired = false, want true")
+	}
+	if !cfg.SMTP.AllowInsecureAuth {
+		t.Fatal("SMTP.AllowInsecureAuth = false, want true")
+	}
+	if cfg.HTTP.Host != "127.0.0.1" || cfg.HTTP.Port != 8765 {
+		t.Fatalf("HTTP default = %s:%d", cfg.HTTP.Host, cfg.HTTP.Port)
+	}
+}