package common

import (
	"encoding/json"
	"fmt"
)

// FaceCamSettings is shared by the SDK and the game heartbeat. Distance is in
// world units; changing this setting never changes the Freecam enabled state.
type FaceCamSettings struct {
	Mode     string  `json:"mode"`
	Distance float64 `json:"distance"`
}

func ReadFaceCamSettings() (FaceCamSettings, error) {
	settings := FaceCamSettings{Mode: "freecam", Distance: 2}
	root, err := readCurrencyWarsPersistentRoot()
	if err != nil {
		return settings, err
	}
	if raw, ok := root["camera_settings"]; ok {
		if err := json.Unmarshal(raw, &settings); err != nil {
			return settings, err
		}
	}
	return settings, settings.Validate()
}

func (s FaceCamSettings) Validate() error {
	if (s.Mode != "freecam" && s.Mode != "facecam") || !(s.Distance >= 0.5 && s.Distance <= 5) {
		return fmt.Errorf("invalid camera mode or distance")
	}
	return nil
}

func SaveFaceCamSettings(settings FaceCamSettings) error {
	if err := settings.Validate(); err != nil {
		return err
	}
	persistentWriteMu.Lock()
	defer persistentWriteMu.Unlock()
	unlock, err := lockPersistentFile()
	if err != nil {
		return err
	}
	defer unlock()
	root, err := readCurrencyWarsPersistentRoot()
	if err != nil {
		return err
	}
	root["camera_settings"], err = json.Marshal(settings)
	if err != nil {
		return err
	}
	return writeJSONAtomic("persistent", root)
}