package config

import (
	"fmt"
	"os"
)

// Config holds application configuration loaded from environment variables.
type Config struct {
	// GiteaURL is the base URL of the Gitea instance.
	GiteaURL string

	// GiteaToken is the default API token (optional; users can set their own via cookie).
	GiteaToken string

	// ListenAddr is the server listen address.
	ListenAddr string

	// SessionSecret is the HMAC key for signing session cookies.
	SessionSecret string
}

// Load reads configuration from environment variables.
// Returns an error if required variables are missing.
func Load() (*Config, error) {
	cfg := &Config{
		GiteaURL:      os.Getenv("GITEA_URL"),
		GiteaToken:    os.Getenv("GITEA_TOKEN"),
		ListenAddr:    os.Getenv("LISTEN_ADDR"),
		SessionSecret: os.Getenv("SESSION_SECRET"),
	}

	if cfg.ListenAddr == "" {
		cfg.ListenAddr = ":8080"
	}

	if cfg.GiteaURL == "" {
		return nil, fmt.Errorf("GITEA_URL environment variable is required")
	}

	if cfg.SessionSecret == "" {
		return nil, fmt.Errorf("SESSION_SECRET environment variable is required")
	}

	if len(cfg.SessionSecret) < 32 {
		return nil, fmt.Errorf("SESSION_SECRET must be at least 32 characters")
	}

	return cfg, nil
}