package fsutil

import (
	"fmt"
	"os"
	"path/filepath"
	goruntime "runtime"
	"strings"
)

// NormalizePathInput standardizes separators from user/config input before
// path resolution so Windows-style relative paths still work on Linux/macOS.
func NormalizePathInput(p string) string {
	p = strings.TrimSpace(p)
	if p == "" {
		return ""
	}

	p = strings.ReplaceAll(p, `\`, string(filepath.Separator))
	p = strings.ReplaceAll(p, `/`, string(filepath.Separator))
	cleaned := filepath.Clean(p)
	if cleaned == "." {
		return ""
	}
	return cleaned
}

// ValidateExecutable checks whether a file is runnable on the current platform.
func ValidateExecutable(path string) error {
	info, err := os.Stat(path)
	if err != nil {
		return err
	}
	if info.IsDir() {
		return fmt.Errorf("目标是目录，不是可执行文件")
	}
	if goruntime.GOOS == "windows" {
		return nil
	}
	if info.Mode()&0o111 == 0 {
		return fmt.Errorf("文件缺少执行权限")
	}
	return nil
}

// EnsureExecutable attempts to repair missing execute bits on non-Windows
// systems so repository-pinned runtime binaries can run from source checkout.
func EnsureExecutable(path string) error {
	if goruntime.GOOS == "windows" {
		return ValidateExecutable(path)
	}

	info, err := os.Stat(path)
	if err != nil {
		return err
	}
	if info.IsDir() {
		return fmt.Errorf("目标是目录，不是可执行文件")
	}
	if info.Mode()&0o111 != 0 {
		return nil
	}

	nextMode := info.Mode() | 0o111
	if err := os.Chmod(path, nextMode); err != nil {
		return fmt.Errorf("补充执行权限失败: %w", err)
	}
	return nil
}