package system_check

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

var numberRegex *regexp.Regexp = regexp.MustCompile(`\d+`)

func getLinuxRamInfo() (MemoryInformation, error) {
	memoryFile, err := os.Open("/proc/meminfo")
	if err != nil {
		return MemoryInformation{}, fmt.Errorf("Could not find /proc/meminfo. Are you sure you are on linux?")
	}
	fileReader := bufio.NewScanner(memoryFile)

	var TotalMemory uint64
	var AvailMemory uint64

	for fileReader.Scan() {

		if fileReader.Err() != nil {
			return MemoryInformation{}, fmt.Errorf("There was an error while reading /proc/meninfo. Error: %v", fileReader.Err())
		}

		line := fileReader.Text()

		if strings.Contains(line, "MemTotal") {
			TotalMemory, err = strconv.ParseUint(numberRegex.FindString(line), 10, 64)
			if err != nil {
				return MemoryInformation{}, fmt.Errorf("Could not parse total memory from /proc/meminfo")
			}
		} else if strings.Contains(line, "MemAvailable") {
			AvailMemory, err = strconv.ParseUint(numberRegex.FindString(line), 10, 64)
			if err != nil {
				return MemoryInformation{}, fmt.Errorf("Could not parse available memory from /proc/meminfo")
			}
		}
	}

	return MemoryInformation{
		SystemMemory:    TotalMemory,
		AvailableMemory: AvailMemory,
	}, nil
}