package isphere

import (
	"bufio"
	"fmt"
	"os"
	"strings"
)

func LoadEncryptedPacketLogSourceFromFile(path string) (EncryptedPacketLogSource, error) {
	trimmedPath := strings.TrimSpace(path)
	if trimmedPath == "" {
		return EncryptedPacketLogSource{}, fmt.Errorf("packet log file path is empty")
	}

	file, err := os.Open(trimmedPath)
	if err != nil {
		return EncryptedPacketLogSource{}, fmt.Errorf("open packet log file %q: %w", trimmedPath, err)
	}
	defer file.Close()

	scanner := bufio.NewScanner(file)
	scanner.Buffer(make([]byte, 64*1024), 16*1024*1024)
	lines := []string{}
	for scanner.Scan() {
		line := strings.TrimSpace(scanner.Text())
		if line == "" {
			continue
		}
		lines = append(lines, line)
	}
	if err := scanner.Err(); err != nil {
		return EncryptedPacketLogSource{}, fmt.Errorf("read packet log file %q: %w", trimmedPath, err)
	}
	return EncryptedPacketLogSource{Lines: lines}, nil
}