package main

import (
	"bufio"
	"flag"
	"fmt"
	"io"
	"os"

	"apigo.cc/go/log"
)

func main() {
	jsonMode := flag.Bool("json", false, "output in JSON format")
	helpMode := flag.Bool("h", false, "show help")
	flag.BoolVar(helpMode, "help", false, "show help")
	
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage: logv [options] [file1 file2 ...]\n")
		fmt.Fprintf(os.Stderr, "Options:\n")
		flag.PrintDefaults()
		fmt.Fprintf(os.Stderr, "\nExamples:\n")
		fmt.Fprintf(os.Stderr, "  1. 彩色可视化实时日志:\n")
		fmt.Fprintf(os.Stderr, "     tail -f app.log | logv\n")
		fmt.Fprintf(os.Stderr, "  2. 格式化查看历史日志文件:\n")
		fmt.Fprintf(os.Stderr, "     logv error.log\n")
		fmt.Fprintf(os.Stderr, "  3. 还原为标准 JSON 格式 (供 Filebeat / Logstash 收集):\n")
		fmt.Fprintf(os.Stderr, "     tail -f app.log | logv -json\n")
		fmt.Fprintf(os.Stderr, "  4. 批量转换日志文件为 JSON:\n")
		fmt.Fprintf(os.Stderr, "     logv -json app.log.2026* > all_logs.json\n")
	}

	flag.Parse()

	if *helpMode {
		flag.Usage()
		return
	}

	// Try to load meta file from current directory
	_ = log.LoadMeta(".log.meta.json")

	args := flag.Args()
	if len(args) == 0 {
		// Check if stdin is a terminal
		stat, _ := os.Stdin.Stat()
		if (stat.Mode() & os.ModeCharDevice) != 0 {
			// Stdin is a terminal and no files provided, show usage
			flag.Usage()
			return
		}
		process(os.Stdin, *jsonMode)
	} else {
		for _, arg := range args {
			f, err := os.Open(arg)
			if err != nil {
				fmt.Fprintf(os.Stderr, "logv: %v\n", err)
				continue
			}
			process(f, *jsonMode)
			f.Close()
		}
	}
}

func process(r io.Reader, jsonMode bool) {
	scanner := bufio.NewScanner(r)
	for scanner.Scan() {
		line := scanner.Text()
		if len(line) == 0 {
			continue
		}
		
		if jsonMode {
			fmt.Println(log.ToJSON(line))
		} else {
			fmt.Println(log.Viewable(line))
		}
	}

	if err := scanner.Err(); err != nil {
		fmt.Fprintf(os.Stderr, "logv: error reading input: %v\n", err)
	}
}