// Package config provides application configuration using smartconfig.
package config

import (
	"fmt"
	"os"
	"path/filepath"

	"git.eeqj.de/sneak/smartconfig"
	"go.uber.org/fx"
	"sneak.berlin/go/pixa/internal/globals"
	"sneak.berlin/go/pixa/internal/logger"
)

// Default configuration values.
const (
	DefaultPort     = 8080
	DefaultStateDir = "./data"
)

// Params defines dependencies for Config.
type Params struct {
	fx.In
	Globals *globals.Globals
	Logger  *logger.Logger
}

// Config holds application configuration values.
type Config struct {
	Debug           bool
	MaintenanceMode bool
	MetricsPassword string
	MetricsUsername string
	Port            int
	SentryDSN       string
	StateDir        string
	DBURL           string
}

// New creates a new Config instance by loading configuration from file.
func New(_ fx.Lifecycle, params Params) (*Config, error) {
	log := params.Logger.Get()
	name := params.Globals.Appname

	var sc *smartconfig.Config
	var err error

	// Try loading config from standard locations
	configPaths := []string{
		fmt.Sprintf("/etc/%s/config.yml", name),
		fmt.Sprintf("/etc/%s/config.yaml", name),
		filepath.Join(os.Getenv("HOME"), ".config", name, "config.yml"),
		filepath.Join(os.Getenv("HOME"), ".config", name, "config.yaml"),
		"config.yml",
		"config.yaml",
	}

	for _, path := range configPaths {
		if _, statErr := os.Stat(path); statErr == nil {
			sc, err = smartconfig.NewFromConfigPath(path)
			if err == nil {
				log.Info("loaded config file", "path", path)

				break
			}
			log.Warn("failed to parse config file", "path", path, "error", err)
		}
	}

	if sc == nil {
		log.Info("no config file found, using defaults")
	}

	c := &Config{
		Debug:           getBool(sc, "debug", false),
		MaintenanceMode: getBool(sc, "maintenance_mode", false),
		Port:            getInt(sc, "port", DefaultPort),
		StateDir:        getString(sc, "state_dir", DefaultStateDir),
		SentryDSN:       getString(sc, "sentry_dsn", ""),
		MetricsUsername: getString(sc, "metrics.username", ""),
		MetricsPassword: getString(sc, "metrics.password", ""),
	}

	// Build DBURL from StateDir if not explicitly set
	c.DBURL = getString(sc, "db_url", "")
	if c.DBURL == "" {
		c.DBURL = fmt.Sprintf("file:%s/state.sqlite3?_journal_mode=WAL", c.StateDir)
	}

	if c.Debug {
		params.Logger.EnableDebugLogging()
	}

	return c, nil
}

func getString(sc *smartconfig.Config, key, defaultVal string) string {
	if sc == nil {
		return defaultVal
	}

	val, err := sc.GetString(key)
	if err != nil {
		return defaultVal
	}

	return val
}

func getInt(sc *smartconfig.Config, key string, defaultVal int) int {
	if sc == nil {
		return defaultVal
	}

	val, err := sc.GetInt(key)
	if err != nil {
		return defaultVal
	}

	return val
}

func getBool(sc *smartconfig.Config, key string, defaultVal bool) bool {
	if sc == nil {
		return defaultVal
	}

	val, err := sc.GetBool(key)
	if err != nil {
		return defaultVal
	}

	return val
}