// Package envutil provide some commonly ENV util functions.
package envutil

import (
	"os"
	"strings"

	"github.com/gookit/goutil/internal/comfunc"
	"github.com/gookit/goutil/internal/varexpr"
)

// ValueGetter Env value provider func.
//
// TIPS: you can custom provide data.
var ValueGetter = os.Getenv

// VarReplace replaces ${var} or $var in the string according to the values.
//
// is alias of the os.ExpandEnv()
func VarReplace(s string) string { return os.ExpandEnv(s) }

// ParseOrErr parse ENV var value from input string, support default value.
//
// Diff with the ParseValue, this support return error.
//
// With error format: ${VAR_NAME | ?error}
func ParseOrErr(val string) (string, error) {
	return varexpr.Parse(val)
}

// ParseValue parse ENV var value from input string, support default value.
//
// Format:
//
//	${var_name}            Only var name
//	${var_name | default}  With default value
//
// Usage:
//
//	envutil.ParseValue("${ APP_NAME }")
//	envutil.ParseValue("${ APP_ENV | dev }")
func ParseValue(val string) string {
	return varexpr.SafeParse(val)
}

// VarParse alias of the ParseValue
func VarParse(val string) string { return varexpr.SafeParse(val) }

// ParseEnvValue alias of the ParseValue
func ParseEnvValue(val string) string { return varexpr.SafeParse(val) }

// SplitText2map parse ENV text to map. Can use to parse .env file contents.
func SplitText2map(text string) map[string]string {
	envMp, _ := comfunc.ParseEnvLines(text, comfunc.ParseEnvLineOption{
		SkipOnErrorLine: true,
	})
	return envMp
}

// SplitLineToKv parse ENV line to k-v. eg: 'DEBUG=true' => ['DEBUG', 'true']
func SplitLineToKv(line string) (string, string) {
	if line = strings.TrimSpace(line); line == "" {
		return "", ""
	}
	return comfunc.SplitLineToKv(line, "=")
}