package controllers

import (
	"Tech/common"
	"encoding/json"
	"os"
	"path/filepath"
	"strings"

	beego "github.com/beego/beego/v2/server/web"
	"github.com/sirupsen/logrus"
)

type LogController struct {
	beego.Controller
}

// LogList 获取日志文件列表
func (c *LogController) LogList() {
	// 验证用户权限
	userName := c.Ctx.Input.Header("userName")
	if userName == "" {
		c.Ctx.Output.SetStatus(401)
		c.Data["json"] = map[string]interface{}{
			"code": 401,
			"msg":  "未提供认证信息",
		}
		c.ServeJSON()
		return
	}

	// 记录操作日志
	clientIP := c.Ctx.Input.IP()
	common.LogUserAction("", userName, "log_list", "system", logrus.Fields{
		"ip": clientIP,
	})

	// 获取日志文件信息
	logFiles, err := common.GetLogFilesInfo()
	if err != nil {
		c.Ctx.Output.SetStatus(500)
		c.Data["json"] = map[string]interface{}{
			"code": 500,
			"msg":  "获取日志文件信息失败: " + err.Error(),
		}
		c.ServeJSON()
		return
	}

	c.Data["json"] = map[string]interface{}{
		"code": 200,
		"data": logFiles,
		"msg":  "获取成功",
	}
	c.ServeJSON()
}

// LogView 查看日志文件内容
func (c *LogController) LogView() {
	// 验证用户权限
	userName := c.Ctx.Input.Header("userName")
	if userName == "" {
		c.Ctx.Output.SetStatus(401)
		c.Data["json"] = map[string]interface{}{
			"code": 401,
			"msg":  "未提供认证信息",
		}
		c.ServeJSON()
		return
	}

	type LogViewRequest struct {
		FileName string `json:"fileName"`
		Lines    int    `json:"lines"`    // 读取的行数，默认100
		Offset   int    `json:"offset"`   // 从末尾开始的偏移量，默认0
	}

	var req LogViewRequest
	if err := json.Unmarshal(c.Ctx.Input.RequestBody, &req); err != nil {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "请求参数格式错误: " + err.Error(),
		}
		c.ServeJSON()
		return
	}

	// 设置默认值
	if req.Lines <= 0 {
		req.Lines = 100
	}

	// 验证文件名，防止路径遍历攻击
	if strings.Contains(req.FileName, "..") || strings.Contains(req.FileName, "/") || strings.Contains(req.FileName, "\\") {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "非法的文件名",
		}
		c.ServeJSON()
		return
	}

	// 检查文件是否是日志文件
	if !strings.HasPrefix(req.FileName, "info") && !strings.HasPrefix(req.FileName, "warn") && !strings.HasPrefix(req.FileName, "error") || !strings.HasSuffix(req.FileName, ".log") && !strings.HasSuffix(req.FileName, ".log.gz") {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "非日志文件",
		}
		c.ServeJSON()
		return
	}

	// 构建文件完整路径
	logDir := filepath.Join(".", "log")
	filePath := filepath.Join(logDir, req.FileName)

	// 检查文件是否存在
	if _, err := os.Stat(filePath); os.IsNotExist(err) {
		c.Ctx.Output.SetStatus(404)
		c.Data["json"] = map[string]interface{}{
			"code": 404,
			"msg":  "文件不存在",
		}
		c.ServeJSON()
		return
	}

	// 读取文件内容
	var content string
	var err error

	if strings.HasSuffix(req.FileName, ".gz") {
		// 压缩文件需要特殊处理，这里简化处理，返回提示信息
		content = "压缩文件暂不支持在线查看，请下载后查看"
	} else {
		content, err = readLastLines(filePath, req.Lines, req.Offset)
		if err != nil {
			c.Ctx.Output.SetStatus(500)
			c.Data["json"] = map[string]interface{}{
				"code": 500,
				"msg":  "读取文件失败: " + err.Error(),
			}
			c.ServeJSON()
			return
		}
	}

	// 记录操作日志
	clientIP := c.Ctx.Input.IP()
	common.LogUserAction("", userName, "log_view", "system", logrus.Fields{
		"ip":       clientIP,
		"file_name": req.FileName,
		"lines":    req.Lines,
		"offset":   req.Offset,
	})

	c.Data["json"] = map[string]interface{}{
		"code": 200,
		"data": map[string]interface{}{
			"content": content,
			"file":    req.FileName,
		},
		"msg": "获取成功",
	}
	c.ServeJSON()
}

// LogDownload 下载日志文件
func (c *LogController) LogDownload() {
	// 验证用户权限
	userName := c.Ctx.Input.Header("userName")
	if userName == "" {
		c.Ctx.Output.SetStatus(401)
		c.Data["json"] = map[string]interface{}{
			"code": 401,
			"msg":  "未提供认证信息",
		}
		c.ServeJSON()
		return
	}

	fileName := c.GetString("fileName")
	if fileName == "" {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "文件名不能为空",
		}
		c.ServeJSON()
		return
	}

	// 验证文件名，防止路径遍历攻击
	if strings.Contains(fileName, "..") || strings.Contains(fileName, "/") || strings.Contains(fileName, "\\") {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "非法的文件名",
		}
		c.ServeJSON()
		return
	}

	// 检查文件是否是日志文件
	if !strings.HasPrefix(fileName, "info") && !strings.HasPrefix(fileName, "warn") && !strings.HasPrefix(fileName, "error") || !strings.HasSuffix(fileName, ".log") && !strings.HasSuffix(fileName, ".log.gz") {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "非日志文件",
		}
		c.ServeJSON()
		return
	}

	// 构建文件完整路径
	logDir := filepath.Join(".", "log")
	filePath := filepath.Join(logDir, fileName)

	// 检查文件是否存在
	if _, err := os.Stat(filePath); os.IsNotExist(err) {
		c.Ctx.Output.SetStatus(404)
		c.Data["json"] = map[string]interface{}{
			"code": 404,
			"msg":  "文件不存在",
		}
		c.ServeJSON()
		return
	}

	// 记录操作日志
	clientIP := c.Ctx.Input.IP()
	common.LogUserAction("", userName, "log_download", "system", logrus.Fields{
		"ip":       clientIP,
		"file_name": fileName,
	})

	// 设置下载响应头
	c.Ctx.Output.Download(filePath, fileName)
}

// LogLevelSet 设置日志级别
func (c *LogController) LogLevelSet() {
	// 验证用户权限
	userName := c.Ctx.Input.Header("userName")
	if userName == "" {
		c.Ctx.Output.SetStatus(401)
		c.Data["json"] = map[string]interface{}{
			"code": 401,
			"msg":  "未提供认证信息",
		}
		c.ServeJSON()
		return
	}

	type LogLevelRequest struct {
		Level string `json:"level"`
	}

	var req LogLevelRequest
	if err := json.Unmarshal(c.Ctx.Input.RequestBody, &req); err != nil {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "请求参数格式错误: " + err.Error(),
		}
		c.ServeJSON()
		return
	}

	// 验证日志级别
	validLevels := map[string]bool{
		"trace": true,
		"debug": true,
		"info":  true,
		"warn":  true,
		"error": true,
		"fatal": true,
		"panic": true,
	}

	if !validLevels[req.Level] {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "无效的日志级别",
		}
		c.ServeJSON()
		return
	}

	// 设置日志级别
	err := common.SetLogLevel(req.Level)
	if err != nil {
		c.Ctx.Output.SetStatus(500)
		c.Data["json"] = map[string]interface{}{
			"code": 500,
			"msg":  "设置日志级别失败: " + err.Error(),
		}
		c.ServeJSON()
		return
	}

	// 记录操作日志
	clientIP := c.Ctx.Input.IP()
	common.LogUserAction("", userName, "log_level_set", "system", logrus.Fields{
		"ip":     clientIP,
		"level":  req.Level,
	})

	c.Data["json"] = map[string]interface{}{
		"code": 200,
		"msg":  "设置成功",
	}
	c.ServeJSON()
}

// LogDelete 删除日志文件
func (c *LogController) LogDelete() {
	// 验证用户权限
	userName := c.Ctx.Input.Header("userName")
	if userName == "" {
		c.Ctx.Output.SetStatus(401)
		c.Data["json"] = map[string]interface{}{
			"code": 401,
			"msg":  "未提供认证信息",
		}
		c.ServeJSON()
		return
	}

	type LogDeleteRequest struct {
		FileName string `json:"fileName"`
	}

	var req LogDeleteRequest
	if err := json.Unmarshal(c.Ctx.Input.RequestBody, &req); err != nil {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "请求参数格式错误: " + err.Error(),
		}
		c.ServeJSON()
		return
	}

	// 验证文件名，防止路径遍历攻击
	if strings.Contains(req.FileName, "..") || strings.Contains(req.FileName, "/") || strings.Contains(req.FileName, "\\") {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "非法的文件名",
		}
		c.ServeJSON()
		return
	}

	// 检查文件是否是日志文件
	if !strings.HasPrefix(req.FileName, "info") && !strings.HasPrefix(req.FileName, "warn") && !strings.HasPrefix(req.FileName, "error") || !strings.HasSuffix(req.FileName, ".log") && !strings.HasSuffix(req.FileName, ".log.gz") {
		c.Ctx.Output.SetStatus(400)
		c.Data["json"] = map[string]interface{}{
			"code": 400,
			"msg":  "非日志文件",
		}
		c.ServeJSON()
		return
	}

	// 构建文件完整路径
	logDir := filepath.Join(".", "log")
	filePath := filepath.Join(logDir, req.FileName)

	// 检查文件是否存在
	if _, err := os.Stat(filePath); os.IsNotExist(err) {
		c.Ctx.Output.SetStatus(404)
		c.Data["json"] = map[string]interface{}{
			"code": 404,
			"msg":  "文件不存在",
		}
		c.ServeJSON()
		return
	}

	// 删除文件
	err := os.Remove(filePath)
	if err != nil {
		c.Ctx.Output.SetStatus(500)
		c.Data["json"] = map[string]interface{}{
			"code": 500,
			"msg":  "删除文件失败: " + err.Error(),
		}
		c.ServeJSON()
		return
	}

	// 记录操作日志
	clientIP := c.Ctx.Input.IP()
	common.LogUserAction("", userName, "log_delete", "system", logrus.Fields{
		"ip":       clientIP,
		"file_name": req.FileName,
	})

	c.Data["json"] = map[string]interface{}{
		"code": 200,
		"msg":  "删除成功",
	}
	c.ServeJSON()
}

// readLastLines 读取文件最后N行
func readLastLines(filePath string, lines int, offset int) (string, error) {
	// 读取文件内容
	content, err := os.ReadFile(filePath)
	if err != nil {
		return "", err
	}

	// 按行分割
	allLines := strings.Split(string(content), "\n")
	
	// 计算起始索引
	startIndex := len(allLines) - lines - offset
	if startIndex < 0 {
		startIndex = 0
	}

	// 截取需要的行
	resultLines := allLines[startIndex : len(allLines)-offset]
	
	return strings.Join(resultLines, "\n"), nil
}