first working commit

command.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"fmt"
+	"strconv"
+)
+
+func (app *App) Send(data string) (num int, err error) {
+	if _, err := fmt.Fprintf(app.conn, "SEND %s\n", data); err != nil {
+		return 0, err
+	}
+
+	if !app.scanner.Scan() {
+		return 0, app.scanner.Err()
+	}
+	numRaw := app.scanner.Text()
+	num, err = strconv.Atoi(numRaw)
+	if err != nil {
+		return 0, err
+	}
+	return num, nil
+}
+
+func (app *App) Poll(since int) (num int, err error) {
+	if _, err := fmt.Fprintf(app.conn, "POLL %d\n", since); err != nil {
+		return 0, err
+	}
+
+	if !app.scanner.Scan() {
+		return 0, app.scanner.Err()
+	}
+	numRaw := app.scanner.Text()
+	num, err = strconv.Atoi(numRaw)
+	if err != nil {
+		return 0, err
+	}
+	return num, nil
+}
+
+func (app *App) Last(n int) (err error) {
+	if _, err := fmt.Fprintf(app.conn, "LAST %d\n", n); err != nil {
+		return err
+	}
+
+	var nsrv int
+	if !app.scanner.Scan() {
+		return app.scanner.Err()
+	}
+	nsrvRaw := app.scanner.Text()
+	nsrv, err = strconv.Atoi(nsrvRaw)
+	if err != nil {
+		return err
+	}
+
+	for range nsrv {
+		if !app.scanner.Scan() {
+			return app.scanner.Err()
+		}
+		app.incoming <- Message(app.scanner.Text())
+	}
+
+	var last int
+	if !app.scanner.Scan() {
+		return app.scanner.Err()
+	}
+	lastRaw := app.scanner.Text()
+	last, err = strconv.Atoi(lastRaw)
+	if err != nil {
+		return err
+	}
+	app.incoming <- SetLast(last)
+
+	return nil
+}