// Package linux 提供Linux平台安装包构建功能
package linux

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strings"

	"git.kingecg.top/kingecg/installerbuilder/internal/builder"
	"git.kingecg.top/kingecg/installerbuilder/internal/config"
	"git.kingecg.top/kingecg/installerbuilder/internal/logger"
)

// DEBBuilder 是Linux DEB安装包构建器
type DEBBuilder struct {
	config    *config.Config
	outputDir string
}

// 确保DEBBuilder实现了Builder接口
var _ builder.Builder = (*DEBBuilder)(nil)

// 注册构建器
func init() {
	builder.RegisterBuilder("linux-deb", func(cfg *config.Config, outputDir string) builder.Builder {
		return NewDEBBuilder(cfg, outputDir)
	})
}

// NewDEBBuilder 创建一个新的DEB构建器
func NewDEBBuilder(cfg *config.Config, outputDir string) *DEBBuilder {
	return &DEBBuilder{
		config:    cfg,
		outputDir: outputDir,
	}
}

// Name 返回构建器名称
func (b *DEBBuilder) Name() string {
	return "Linux DEB Builder"
}

// SupportedPlatforms 返回支持的平台列表
func (b *DEBBuilder) SupportedPlatforms() []string {
	return []string{"linux"}
}

// SupportedFormats 返回支持的格式列表
func (b *DEBBuilder) SupportedFormats() []string {
	return []string{"deb"}
}

// Build 构建DEB安装包
func (b *DEBBuilder) Build() error {
	logger.Info("开始构建Linux DEB安装包")

	// 创建临时工作目录
	workDir, err := os.MkdirTemp("", "installer-builder-deb-*")
	if err != nil {
		return fmt.Errorf("创建临时工作目录失败: %w", err)
	}
	defer os.RemoveAll(workDir)

	logger.Debugf("使用临时工作目录: %s", workDir)

	// 创建DEB包结构
	if err := b.createDebStructure(workDir); err != nil {
		return fmt.Errorf("创建DEB包结构失败: %w", err)
	}

	// 复制文件到临时目录
	if err := b.copyFiles(workDir); err != nil {
		return fmt.Errorf("复制文件失败: %w", err)
	}

	// 创建控制文件
	if err := b.createControlFile(workDir); err != nil {
		return fmt.Errorf("创建控制文件失败: %w", err)
	}

	// 创建安装脚本
	if err := b.createScripts(workDir); err != nil {
		return fmt.Errorf("创建安装脚本失败: %w", err)
	}

	// 构建DEB包
	debFile := filepath.Join(b.outputDir, fmt.Sprintf("%s_%s_amd64.deb", b.config.Name, b.config.Version))
	if err := b.buildDeb(workDir, debFile); err != nil {
		return fmt.Errorf("构建DEB包失败: %w", err)
	}

	logger.Infof("成功构建DEB安装包: %s", debFile)
	return nil
}

// createDebStructure 创建DEB包结构
func (b *DEBBuilder) createDebStructure(workDir string) error {
	// 创建DEBIAN目录
	debianDir := filepath.Join(workDir, "DEBIAN")
	if err := os.MkdirAll(debianDir, 0755); err != nil {
		return fmt.Errorf("创建DEBIAN目录失败: %w", err)
	}

	// 创建安装目录
	installDir := filepath.Join(workDir, "usr", "local", "bin")
	if err := os.MkdirAll(installDir, 0755); err != nil {
		return fmt.Errorf("创建安装目录失败: %w", err)
	}

	// 创建文档目录
	docDir := filepath.Join(workDir, "usr", "share", "doc", b.config.Name)
	if err := os.MkdirAll(docDir, 0755); err != nil {
		return fmt.Errorf("创建文档目录失败: %w", err)
	}

	return nil
}

// copyFiles 复制文件到临时目录
func (b *DEBBuilder) copyFiles(workDir string) error {
	// 这里应该实现文件复制逻辑
	// 实际应用中，应该根据配置复制文件到临时目录
	logger.Debug("复制文件到临时目录")
	return nil
}

// createControlFile 创建控制文件
func (b *DEBBuilder) createControlFile(workDir string) error {
	controlFile := filepath.Join(workDir, "DEBIAN", "control")

	// 准备依赖项列表
	var depends string
	if len(b.config.Platforms.Linux.Deb.Depends) > 0 {
		depends = strings.Join(b.config.Platforms.Linux.Deb.Depends, ", ")
	} else {
		depends = ""
	}

	// 准备推荐项列表
	var recommends string
	if len(b.config.Platforms.Linux.Deb.Recommends) > 0 {
		recommends = strings.Join(b.config.Platforms.Linux.Deb.Recommends, ", ")
	} else {
		recommends = ""
	}

	// 准备建议项列表
	var suggests string
	if len(b.config.Platforms.Linux.Deb.Suggests) > 0 {
		suggests = strings.Join(b.config.Platforms.Linux.Deb.Suggests, ", ")
	} else {
		suggests = ""
	}

	// 准备冲突项列表
	var conflicts string
	if len(b.config.Platforms.Linux.Deb.Conflicts) > 0 {
		conflicts = strings.Join(b.config.Platforms.Linux.Deb.Conflicts, ", ")
	} else {
		conflicts = ""
	}

	// 准备替换项列表
	var replaces string
	if len(b.config.Platforms.Linux.Deb.Replaces) > 0 {
		replaces = strings.Join(b.config.Platforms.Linux.Deb.Replaces, ", ")
	} else {
		replaces = ""
	}

	// 创建控制文件内容
	content := fmt.Sprintf(`Package: %s
Version: %s
Section: %s
Priority: %s
Architecture: %s
Maintainer: %s
Description: %s
`,
		b.config.Name,
		b.config.Version,
		b.config.Platforms.Linux.Deb.Section,
		b.config.Platforms.Linux.Deb.Priority,
		b.config.Platforms.Linux.Deb.Architecture,
		b.config.Author,
		b.config.Description)

	// 添加可选字段
	if depends != "" {
		content += fmt.Sprintf("Depends: %s\n", depends)
	}
	if recommends != "" {
		content += fmt.Sprintf("Recommends: %s\n", recommends)
	}
	if suggests != "" {
		content += fmt.Sprintf("Suggests: %s\n", suggests)
	}
	if conflicts != "" {
		content += fmt.Sprintf("Conflicts: %s\n", conflicts)
	}
	if replaces != "" {
		content += fmt.Sprintf("Replaces: %s\n", replaces)
	}

	// 写入控制文件
	return os.WriteFile(controlFile, []byte(content), 0644)
}

// createScripts 创建安装脚本
func (b *DEBBuilder) createScripts(workDir string) error {
	// 脚本类型到文件名的映射
	scriptFiles := map[string]string{
		"preinstall":    "preinst",
		"postinstall":   "postinst",
		"preuninstall":  "prerm",
		"postuninstall": "postrm",
	}

	// 遍历配置中的脚本
	for _, script := range b.config.Contents.Scripts {
		// 检查是否是DEB支持的脚本类型
		filename, ok := scriptFiles[script.Type]
		if !ok {
			logger.Warnf("跳过不支持的脚本类型: %s", script.Type)
			continue
		}

		// 脚本文件路径
		scriptPath := filepath.Join(workDir, "DEBIAN", filename)

		// 获取脚本内容
		var content string
		if script.Content != "" {
			content = script.Content
		} else if script.Source != "" {
			// 从源文件读取脚本内容
			data, err := os.ReadFile(script.Source)
			if err != nil {
				return fmt.Errorf("读取脚本源文件失败: %w", err)
			}
			content = string(data)
		} else {
			logger.Warnf("跳过空脚本: %s", script.Type)
			continue
		}

		// 确保脚本以#!/bin/sh开头
		if !strings.HasPrefix(content, "#!") {
			content = "#!/bin/sh\n" + content
		}

		// 写入脚本文件
		if err := os.WriteFile(scriptPath, []byte(content), 0755); err != nil {
			return fmt.Errorf("写入脚本文件失败: %w", err)
		}

		logger.Debugf("创建脚本文件: %s", scriptPath)
	}

	return nil
}

// buildDeb 构建DEB包
func (b *DEBBuilder) buildDeb(workDir, outputFile string) error {
	// 检查是否安装了dpkg-deb
	dpkgDeb, err := exec.LookPath("dpkg-deb")
	if err != nil {
		return fmt.Errorf("未找到dpkg-deb工具，请确保已安装dpkg-deb并添加到PATH中")
	}

	// 确保输出目录存在
	if err := os.MkdirAll(filepath.Dir(outputFile), 0755); err != nil {
		return fmt.Errorf("创建输出目录失败: %w", err)
	}

	// 构建命令
	cmd := exec.Command(dpkgDeb, "--build", workDir, outputFile)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr

	// 执行命令
	logger.Debugf("执行命令: %s", strings.Join(cmd.Args, " "))
	if err := cmd.Run(); err != nil {
		return fmt.Errorf("执行dpkg-deb命令失败: %w", err)
	}

	return nil
}