package config

import (
	"errors"
	"log/slog"
	"reflect"
)

// JSCKLogging is the logging section's configuration key.
const JSCKLogging string = "logging"

// JSCLogging configures logging. Level is one of debug, info,
// warn or error. File, if set, is where commands that log to a file write;
// empty means they log to the terminal.
type JSCLogging struct {
	Level string `cfg:"level" default:"warn"`
	File  string `cfg:"file"`
}

// ---------- Section methods (see Section) ----------

// Map implements Section.
func (c JSCLogging) Map() map[string]any { return mapOf(c) }

// Flatten implements Section.
func (c JSCLogging) Flatten() map[string]any {
	return flattenOf(JSCKLogging, c)
}

// TypeOf implements Section.
func (c JSCLogging) TypeOf(key string) (reflect.Kind, error) {
	return typeOf(c, key)
}

// ValueOf implements Section.
func (c JSCLogging) ValueOf(key string) (any, error) {
	return valueOf(c, key)
}

// SetValue implements Section.
func (c *JSCLogging) SetValue(key string, value any) error {
	return setValue(c, key, value)
}

// Keys returns the keys directly in the section.
func (c *JSCLogging) Keys() []string { return keysOf(c) }

// ---------- Section specific methods ----------

// validate checks values before they are stored (see validator).
func (c *JSCLogging) validate(key string, value any) error {
	switch key {
	case "level":
		switch value.(string) {
		case "debug", "info", "warn", "error":
		default:
			return errors.New(
				"config: invalid log level: must be one of debug, info, warn, error",
			)
		}
	}
	return nil
}

// LevelToLogLevel converts a configured level name to an slog level. An
// unknown name gives 99, above every real level, so nothing is logged.
func LevelToLogLevel(level string) slog.Level {
	switch level {
	case "debug":
		return slog.LevelDebug
	case "info":
		return slog.LevelInfo
	case "warn":
		return slog.LevelWarn
	case "error":
		return slog.LevelError
	default:
		return 99
	}
}

// LogLevel returns the configured level as an slog level. An unknown level
// gives 99, above every real level, so nothing is logged.
func (c *JSCLogging) LogLevel() slog.Level {
	return LevelToLogLevel(c.Level)
}