// Package uploader 上传数据
package uploader

import (
	"bufio"
	"context"
	"dypid-client/internal/api"
	"dypid-client/internal/config"
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"sync"
	"sync/atomic"
	"time"

	"github.com/wailsapp/wails/v2/pkg/runtime"
	"golang.org/x/sync/errgroup"
)

var progress sync.Map

type Task struct {
	FilePath  string
	FileLines int
}

type Progress struct {
	FileName   string `json:"name"`
	Total      int    `json:"total"`
	Uploaded   int    `json:"uploaded"`
	Percentage int    `json:"percentage"`
}

func StartLooking(ctx context.Context, logChan *chan string, lookingPath string) {
	go func() {
		for {
			time.Sleep(500 * time.Millisecond)

			var pg []Progress
			progress.Range(func(key, value any) bool {
				p := value.(Progress)
				pg = append(pg, p)
				return true
			})
			runtime.EventsEmit(ctx, "progress", pg)
		}
	}()

	for {
		uploadData(ctx, logChan, lookingPath)
		select {
		case <-time.After(time.Minute):
		case <-ctx.Done():
			AddLog(logChan, "上传程序已退出")
			return
		}
	}
}

func uploadData(ctx context.Context, logChan *chan string, lookingPath string) {
	var path = "./"
	if lookingPath != "" {
		path = lookingPath
	}

	//获取文件列表
	files, err := getTxtFiles(path)
	if err != nil {
		AddLog(logChan, "获取文件列表失败："+err.Error())
		return
	}
	if files == nil {
		return
	}

	start := time.Now()
	//检测到文件
	//统计文件行数
	fileLines := make(map[string]int)
	AddLog(logChan, fmt.Sprintf("正在统计 %v 个文件行数", len(files)))
	isAllEmpty := true
	for _, filePath := range files {
		select {
		case <-ctx.Done():
			return
		default:
			file, err := os.Open(filePath)
			if err != nil {
				AddLog(logChan, "打开文件失败："+err.Error())
			}
			// 使用 bufio.Scanner 逐行读取
			scanner := bufio.NewScanner(file)
			lineCount := 0
			for scanner.Scan() {
				lineCount++
			}
			err = file.Close()

			if lineCount == 0 {
				continue
			}
			fileLines[filepath.Base(filePath)] = lineCount
			isAllEmpty = false
			AddLog(logChan, fmt.Sprintf("%s 文件行数：%v", filepath.Base(filePath), lineCount))
		}
	}
	if isAllEmpty {
		AddLog(logChan, "所有文件都为空，不进行上传")
		return
	}

	//添加文件上传任务参数（文件路径，文件行数）
	var tasks []Task
	for k, v := range fileLines {
		tasks = append(tasks, Task{FilePath: path + "/" + k, FileLines: v})
	}

	// 使用 errgroup 控制同时处理的文件数，并开始上传文件任务
	g, egctx := errgroup.WithContext(ctx)
	g.SetLimit(config.APPConfig.HandleFileCount) // 设置同时处理文件数
	// 执行所有任务
	for _, task := range tasks {
		g.Go(func() error {
			select {
			case <-egctx.Done():
				return egctx.Err()
			default:
				AddLog(logChan, "正在上传文件："+filepath.Base(task.FilePath))

				processFile(egctx, logChan, task.FilePath, task.FileLines)

				//上传完成，清空文件
				err := os.Truncate(task.FilePath, 0)
				if err != nil {
					AddLog(logChan, "清空文件失败："+err.Error())
				}
				return nil
			}
		})
	}

	// 等待所有任务完成
	if err := g.Wait(); err != nil {
		AddLog(logChan, fmt.Sprintf("任务执行出错: %v", err))
	} else {
		AddLog(logChan, "所有任务执行完成！")
	}

	AddLog(logChan, fmt.Sprintf("上传完成，耗时：%s", time.Since(start).String()))
	progress.Clear()
}

// 获取目录中的所有txt文件
func getTxtFiles(dir string) (txtFiles []string, err error) {
	err = filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}

		// 只处理普通文件，跳过目录
		if !info.Mode().IsRegular() {
			return nil
		}

		// 检查文件扩展名是否为.txt
		if strings.ToLower(filepath.Ext(path)) == ".txt" {
			txtFiles = append(txtFiles, path)
		}

		return nil
	})

	return txtFiles, err
}

func processFile(ctx context.Context, logChan *chan string, filePath string, fileLines int) {
	var wg sync.WaitGroup
	// 打开文件
	file, err := os.Open(filePath)
	if err != nil {
		AddLog(logChan, fmt.Sprintf("[processFile] 无法打开文件 %s: %v", filePath, err))
		return
	}
	defer file.Close()

	// 创建行通道
	lines := make(chan string, 100)
	var countLine int32 = 0
	// 创建指定个worker同时处理文件上传
	for i := 0; i < config.APPConfig.ThreadCount; i++ {
		wg.Go(func() {
			processLines(ctx, logChan, &lines, i, filePath, &countLine)
		})
	}

	// 读取文件并发送到通道
	scanner := bufio.NewScanner(file)
	go func() {
		for scanner.Scan() {
			select {
			case <-ctx.Done():
				return
			default:
				lines <- scanner.Text()
			}
		}
	}()

	for int(countLine) != fileLines {
		select {
		case <-ctx.Done():
			close(lines)
			wg.Wait()
			return
		default:
			progress.Store(filepath.Base(filePath),
				Progress{FileName: filepath.Base(filePath),
					Total: fileLines, Uploaded: int(countLine),
					Percentage: int(float64(countLine)/float64(fileLines)*100) + 1,
				})
			time.Sleep(500 * time.Millisecond)
		}
	}

	close(lines)
	wg.Wait()

	if err := scanner.Err(); err != nil {
		AddLog(logChan, fmt.Sprintf("读取文件 %s 错误: %v", filePath, err))
		return
	}

	AddLog(logChan, fmt.Sprintf("文件【%s】处理完成，共处理 %d 行数据", filePath, countLine))
}

func processLines(ctx context.Context, logChan *chan string, lines *chan string, workerID int, filePath string, countLine *int32) {
	for line := range *lines {
		select {
		case <-ctx.Done():
			return
		default:
			// 跳过空行
			if strings.TrimSpace(line) == "" {
				continue
			}
			// 上传数据
			if err := api.UploadDataToServer(line); err != nil {
				AddLog(logChan, fmt.Sprintf("Worker %d (文件 %s): 上传失败: %v", workerID, filePath, err))
			}
			atomic.AddInt32(countLine, 1)
		}
	}
}

func AddLog(logChan *chan string, message string) {
	*logChan <- message
}