package main

import (
	"bufio"
	"flag"
	"fmt"
	"log/slog"
	"os"

	"git.algo.com.cn/public/bloomtool/internal/bloom"
)

func RunHitTest(args ...string) error {
	fs := flag.NewFlagSet("hittest", flag.ExitOnError)

	txtFile := fs.String("d", "", "device id filename")
	bmpFile := fs.String("b", "", "bitmap filename")
	outStateFile := fs.String("o", "", "state filename for output")
	filter := fs.Bool("f", false, "filter for hit only")

	if err := fs.Parse(args); err != nil {
		return err
	} else if fs.NArg() > 0 || *txtFile == "" || *bmpFile == "" || *outStateFile == "" {
		fmt.Println(fs.NArg())
		fs.Usage()
		return nil
	}

	return hitTest(*txtFile, *bmpFile, *outStateFile, *filter)
}

func hitTest(txtFile, bmpFile, stateFile string, filter bool) error {

	slog.Info("load bitmap file", "filename", bmpFile)
	bfile, err := bloom.LoadFromFile(bmpFile, false)
	if err != nil {
		slog.Error("open bitmap file error", "err", err)
		return err
	}

	slog.Info("load text file", "filename", txtFile)
	tfile, err := os.Open(txtFile)
	if err != nil {
		slog.Error("open text file error", "err", err)
		return err
	}
	defer tfile.Close()

	slog.Info("create state file", "filename", stateFile)
	sfile, err := os.Create(stateFile)
	if err != nil {
		slog.Error("create state file error", "err", err)
		return err
	}
	defer sfile.Close()

	writer := bufio.NewWriter(sfile)

	// 逐行读取
	scanner := bufio.NewScanner(tfile)
	lineCount := 1
	lineText := ""
	for scanner.Scan() {
		if lineCount%100000 == 0 {
			slog.Info("read line", "lineno", lineCount)
		}

		// 撞库
		lineText = scanner.Text()
		hit := bfile.TestString(lineText)
		intHit := 0
		if hit {
			intHit = 1
		}
		if filter {
			if hit {
				writer.WriteString(fmt.Sprintf("%v\n", lineText))
			}
		} else {
			writer.WriteString(fmt.Sprintf("%v\t%v\n", lineText, intHit))
		}

		lineCount++
	}
	writer.Flush()

	return nil
}