package transportcfg

import (
	"encoding/json"
	"os"
	"path/filepath"
	"sort"
	"strings"
)

func NormalizeSecretUpdates(in map[string]string) map[string]string {
	if in == nil {
		return nil
	}
	out := make(map[string]string, len(in))
	for k, v := range in {
		key := strings.TrimSpace(k)
		if key == "" {
			continue
		}
		out[key] = v
	}
	return out
}

func CloneStringMap(in map[string]string) map[string]string {
	if len(in) == 0 {
		return nil
	}
	out := make(map[string]string, len(in))
	for k, v := range in {
		out[k] = v
	}
	return out
}

func EqualStringMap(a, b map[string]string) bool {
	if len(a) != len(b) {
		return false
	}
	for k, av := range a {
		if bv, ok := b[k]; !ok || av != bv {
			return false
		}
	}
	return true
}

func MaskStringMap(in map[string]string, mask string) map[string]string {
	if len(in) == 0 {
		return nil
	}
	keys := make([]string, 0, len(in))
	for k := range in {
		keys = append(keys, k)
	}
	sort.Strings(keys)
	out := make(map[string]string, len(keys))
	for _, k := range keys {
		out[k] = mask
	}
	return out
}

func ReadStringMapJSON(path string) (map[string]string, error) {
	data, err := os.ReadFile(path)
	if err != nil {
		if os.IsNotExist(err) {
			return map[string]string{}, nil
		}
		return nil, err
	}
	var raw map[string]string
	if err := json.Unmarshal(data, &raw); err != nil {
		return nil, err
	}
	return NormalizeSecretUpdates(raw), nil
}

func WriteStringMapJSON(path string, values map[string]string, dirPerm, filePerm os.FileMode) error {
	normalized := NormalizeSecretUpdates(values)
	if len(normalized) == 0 {
		if err := os.Remove(path); err != nil && !os.IsNotExist(err) {
			return err
		}
		return nil
	}
	if err := os.MkdirAll(filepath.Dir(path), dirPerm); err != nil {
		return err
	}
	data, err := json.MarshalIndent(normalized, "", "  ")
	if err != nil {
		return err
	}
	tmp := path + ".tmp"
	if err := os.WriteFile(tmp, data, filePerm); err != nil {
		return err
	}
	return os.Rename(tmp, path)
}