package cmd

import (
	"bytes"
	"fmt"
	"github.com/spf13/cobra"
	"io"
	"io/fs"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
)

func getModuleName(goModPath string) (string, error) {
	content, err := os.ReadFile(goModPath)
	if err != nil {
		return "", err
	}

	lines := strings.Split(string(content), "\n")
	for _, line := range lines {
		if strings.HasPrefix(line, "module ") {
			return strings.TrimSpace(strings.TrimPrefix(line, "module ")), nil
		}
	}

	return "", fmt.Errorf("module name not found in go.mod")
}

func handleRemoteTemplate(templateRepo, branch, projectPath string) (err error) {
	// 创建临时目录
	tempDir, err := os.MkdirTemp("", "template-*")
	if err != nil {
		return fmt.Errorf("error creating temporary directory: %s", err)
	}

	// 清理临时目录
	defer os.RemoveAll(tempDir)

	// 克隆模板仓库
	cloneCmd := exec.Command("git", "clone", "--branch", branch, templateRepo, tempDir)
	cloneCmd.Stdout = io.Discard
	var stderr bytes.Buffer
	cloneCmd.Stderr = &stderr

	if err = cloneCmd.Run(); err != nil {
		return fmt.Errorf("error cloning template repository: %s\n%s", err, extractError(stderr.String()))
	}

	return copyTemplate(tempDir, projectPath)
}

func copyTemplate(src, dist string) (err error) {
	// 读取 go.mod 文件中的模块名称
	oldModuleName, err := getModuleName(filepath.Join(src, "go.mod"))
	if err != nil {
		log.Printf("error reading module name: %s", err)
		os.Exit(1)
	}
	replacements := map[string]string{
		oldModuleName: filepath.Base(dist),
	}

	return filepath.Walk(src, func(path string, info fs.FileInfo, err error) error {
		if err != nil {
			return err
		}

		// 获取相对路径
		relPath, err := filepath.Rel(src, path)
		if err != nil {
			return err
		}

		// 获取目标路径
		targetPath := filepath.Join(dist, relPath)

		if info.IsDir() && filepath.Base(path) == ".git" {
			return filepath.SkipDir
		}

		if info.IsDir() {
			// 创建目录
			return os.MkdirAll(targetPath, info.Mode())
		}

		return copyAndReplaceFile(path, targetPath, info.Mode(), replacements)
	})
}

func copyAndReplaceFile(src, dist string, mode os.FileMode, replacements map[string]string) (err error) {

	// 读取源文件
	sourceFile, err := os.Open(src)
	if err != nil {
		return err
	}
	defer sourceFile.Close()

	content, err := io.ReadAll(sourceFile)
	if err != nil {
		return err
	}

	newContent := string(content)
	for key, value := range replacements {
		newContent = strings.ReplaceAll(newContent, key, value)
	}

	// 读取目标文件
	targetFile, err := os.OpenFile(dist, os.O_CREATE|os.O_RDWR|os.O_TRUNC, mode)
	if err != nil {
		return err
	}

	defer targetFile.Close()

	_, err = targetFile.WriteString(newContent)
	return
}

// extractError 解析并提取实际的错误信息
func extractError(stderr string) string {
	lines := strings.Split(stderr, "\n")
	var errorLines []string
	for _, line := range lines {
		// 过滤掉非错误信息
		if strings.HasPrefix(line, "fatal:") || strings.Contains(line, "error:") {
			errorLines = append(errorLines, line)
		}
	}
	return strings.Join(errorLines, "\n")
}

// initFlags 初始化通用的命令行参数
func initFlags(cmd *cobra.Command) {
	cmd.Flags().StringVarP(&project, "project", "p", "", "项目名称")
	cmd.Flags().StringVarP(&branch, "tag", "t", "master", "指定tag")
	cmd.MarkFlagRequired("project")
}