package main
import (
"encoding/json"
"fmt"
"io"
"io/ioutil"
"log"
flag "github.com/docker/docker/pkg/mflag"
"github.com/tarm/serial"
)
type measurement struct {
Header int
Systolic int
Diastolic int
Pulse int
Month int
Day int
Hour int
Minute int
Year int
}
func getData(s io.ReadWriteCloser, buf []byte, size int) (int, error) {
t := 0
b := buf
for t < size {
n, err := s.Read(b[t:])
if err != nil {
log.Fatal(err) // XXX
return t, err
}
//log.Printf("(%d bytes) %q\n", n, b[t:t+1])
t = t + n
}
return t, nil
}
func fetchData(dev string) (items []measurement, err error) {
c := &serial.Config{Name: dev, Baud: 4800}
var s *serial.Port
s, err = serial.OpenPort(c)
if err != nil {
return items, err
}
// =================== Handshake =====================
q := []byte("\xaa")
//log.Printf("Query: %q\n", q)
log.Println("Starting handshake...")
n, err := s.Write(q)
if err != nil {
return items, err
}
buf := make([]byte, 128)
n, err = getData(s, buf, 1)
if err != nil {
return items, err
}
if n == 1 && buf[0] == '\x55' {
log.Println("Handshake successful.")
} else {
log.Printf("(%d bytes) %q\n", n, buf[:n])
s.Close()
return items, fmt.Errorf("handshake failed")
}
// =================== Desc =====================
q = []byte("\xa4")
//log.Printf("Query: %q\n", q)
log.Println("Requesting device description...")
n, err = s.Write(q)
if err != nil {
return items, err
}
n, err = getData(s, buf, 32)
log.Printf("DESC> %q\n", buf[:n])
// =================== Count =====================
q = []byte("\xa2")
//log.Printf("Query: %q\n", q)
log.Println("Requesting data counter...")
n, err = s.Write(q)
if err != nil {
return items, err
}
n, err = getData(s, buf, 1)
if err != nil {
return items, err
}
var nRecords int
if n == 1 {
log.Printf("%d item(s) available.", buf[0])
nRecords = int(buf[0])
} else {
log.Printf("(%d bytes) %q\n", n, buf[:n])
return items, fmt.Errorf("no measurement found")
}
// =================== Records =====================
for i := 0; i < nRecords; i++ {
q = []byte{'\xa3', uint8(i + 1)}
//log.Printf("Query: %q\n", q)
//log.Printf("Requesting measurement %d...", i+1)
n, err = s.Write(q)
if err != nil {
return items, err
}
n, err = getData(s, buf, 9)
//log.Printf("DESC> %q\n", buf[:n])
var data measurement
data.Header = int(buf[0])
data.Systolic = int(buf[1]) + 25
data.Diastolic = int(buf[2]) + 25
data.Pulse = int(buf[3])
data.Month = int(buf[4])
data.Day = int(buf[5])
data.Hour = int(buf[6])
data.Minute = int(buf[7])
data.Year = int(buf[8]) + 2000
items = append(items, data)
}
s.Close()
return items, nil
}
func loadFromJSONFile(filename string) (items []measurement, err error) {
data, err := ioutil.ReadFile(filename)
if err != nil {
return items, err
}
err = json.Unmarshal(data, &items)
return items, err
}
func mergeItems(newItems, oldItems []measurement) []measurement {
var result []measurement
var j int
// TODO: Would be better to compare dates and merge chronologically...
for _, nItem := range newItems {
result = append(result, nItem)
if j+1 <= len(oldItems) && nItem == oldItems[j] {
j++
}
}
if j+1 <= len(oldItems) {
result = append(result, oldItems[j:]...)
}
return result
}
func main() {
inFile := flag.String([]string{"-input-file", "i"}, "", "Input JSON file")
outFile := flag.String([]string{"-output-file", "o"}, "", "Output JSON file")
limit := flag.Uint([]string{"-limit", "l"}, 0, "Limit number of items")
format := flag.String([]string{"-format", "f"}, "", "Output format (csv, json)")
avg := flag.Bool([]string{"-average", "a"}, false, "Compute average")
merge := flag.Bool([]string{"-merge", "m"}, false,
"Try to merge input JSON file with fetched data")
device := flag.String([]string{"-device", "d"}, "/dev/ttyUSB0", "Serial device")
flag.Parse()
switch *format {
case "":
if *outFile == "" {
*format = "csv"
}
break
case "json", "csv":
break
default:
log.Fatal("Unknown output format. Possible choices are csv, json.")
}
var err error
var items []measurement
if *inFile == "" {
// Read from device
if items, err = fetchData(*device); err != nil {
log.Fatal(err)
}
} else {
// Read from file
var fileItems []measurement
if fileItems, err = loadFromJSONFile(*inFile); err != nil {
log.Fatal(err)
}
if *merge {
if items, err = fetchData(*device); err != nil {
log.Fatal(err)
}
items = mergeItems(items, fileItems)
} else {
items = fileItems
}
}
if *limit > 0 && len(items) > int(*limit) {
items = items[0:*limit]
}
var avgMeasure measurement
var avgCount int
for i, data := range items {
if *format == "csv" {
fmt.Printf("%d;%x;%d-%02d-%02d %02d:%02d;%d;%d;%d\n",
i+1, data.Header,
data.Year, data.Month, data.Day,
data.Hour, data.Minute,
data.Systolic, data.Diastolic, data.Pulse)
}
avgMeasure.Systolic += data.Systolic
avgMeasure.Diastolic += data.Diastolic
avgMeasure.Pulse += data.Pulse
avgCount++
}
if *avg && avgCount > 0 {
avgMeasure.Systolic /= avgCount
avgMeasure.Diastolic /= avgCount
avgMeasure.Pulse /= avgCount
fmt.Printf("Average: %d;%d;%d\n", avgMeasure.Systolic,
avgMeasure.Diastolic, avgMeasure.Pulse)
}
if *format == "json" || *outFile != "" {
rawJSON, err := json.MarshalIndent(items, "", " ")
if err != nil {
log.Fatal("Error:", err)
}
if *format == "json" {
fmt.Println(string(rawJSON))
}
if *outFile != "" {
err = ioutil.WriteFile(*outFile, rawJSON, 0600)
if err != nil {
log.Println("Could not write output file:", err)
}
}
}
}