package config
import (
"errors"
"fmt"
"os"
"strings"
)
// Environment variable name constants
const (
EnvPaperlessURL = "PAPERLESS_URL"
EnvPaperlessToken = "PAPERLESS_TOKEN"
EnvMCPAuthToken = "MCP_AUTH_TOKEN"
EnvLogLevel = "LOG_LEVEL"
EnvMCPTransport = "MCP_TRANSPORT"
EnvMCPHTTPPort = "MCP_HTTP_PORT"
)
// Default values
const (
DefaultLogLevel = "info"
DefaultMCPTransport = "stdio"
DefaultMCPHTTPPort = "8080"
)
// Config holds all application configuration
type Config struct {
PaperlessURL string
PaperlessToken string
MCPAuthToken string // optional
LogLevel string
MCPTransport string
MCPHTTPPort string
}
// Load reads configuration from environment variables
func Load() (*Config, error) {
cfg := &Config{}
cfg.PaperlessURL = os.Getenv(EnvPaperlessURL)
if strings.TrimSpace(cfg.PaperlessURL) == "" {
return nil, errors.New("environment variable PAPERLESS_URL is required but not set")
}
cfg.PaperlessToken = os.Getenv(EnvPaperlessToken)
if strings.TrimSpace(cfg.PaperlessToken) == "" {
return nil, errors.New("environment variable PAPERLESS_TOKEN is required but not set")
}
cfg.MCPAuthToken = os.Getenv(EnvMCPAuthToken) // optional, no error if empty
// Optional vars with defaults
cfg.LogLevel = os.Getenv(EnvLogLevel)
if cfg.LogLevel == "" {
cfg.LogLevel = DefaultLogLevel
}
cfg.LogLevel = strings.ToLower(cfg.LogLevel)
allowedLogLevels := map[string]bool{"debug": true, "info": true, "warn": true, "error": true}
if !allowedLogLevels[cfg.LogLevel] {
return nil, fmt.Errorf("invalid log level: %s, allowed: debug, info, warn, error", cfg.LogLevel)
}
cfg.MCPTransport = os.Getenv(EnvMCPTransport)
if cfg.MCPTransport == "" {
cfg.MCPTransport = DefaultMCPTransport
}
cfg.MCPTransport = strings.ToLower(cfg.MCPTransport)
if cfg.MCPTransport != "stdio" && cfg.MCPTransport != "http" {
return nil, fmt.Errorf("invalid MCP_TRANSPORT: %s, allowed: stdio, http", cfg.MCPTransport)
}
cfg.MCPHTTPPort = os.Getenv(EnvMCPHTTPPort)
if cfg.MCPHTTPPort == "" {
cfg.MCPHTTPPort = DefaultMCPHTTPPort
}
// Optional: Could add port format validation here but skipping per spec simplicity
return cfg, nil
}
