guiwrapper.go

package main

import (
	"fmt"
	"strings"
	"sync"
	"time"

	"github.com/awesome-gocui/gocui"
)

type guiwrapper struct {
	gui        *gocui.Gui
	messages   []*guimessage
	maxlines   int
	timeformat string
	sync.RWMutex
}

type guimessage struct {
	ts  time.Time
	tag string // TODO assert len=3 ?
	msg string
	// TODO right now only set this when we want to modify tag/highlight/ignore/... later on... not on "system" messages; even though they technically have a sender too...
	nick string
}

func (gw *guiwrapper) formatMessage(gm *guimessage) string {
	formattedDate := gm.ts.Format(gw.timeformat)
	return fmt.Sprintf("[%s]%s%s", formattedDate, gm.tag, gm.msg)
}

func (gw *guiwrapper) redraw() {
	gw.gui.Update(func(g *gocui.Gui) error {
		messageView, err := g.View("messages")
		if err != nil {
			return err
		}

		// If we have reached maxlines and the user is currently reading old lines,
		// i.e. is in an scrolled-up state, do not redraw, because it makes reading
		// messages very hard... Scroll function should make sure to call redraw()
		// when the user is done reading old messages.
		// This introduces some ugly side-effects, e.g. commands typed into chat like
		// /tag will also not be instantly applied when in a scrolled-up state.
		// Or if the user is scrolled up for a very long time, once scrolling down
		// chat will make a big jump redrawing - All of that probably cannot be helped.
		if !messageView.Autoscroll {
			return nil
		}

		gw.Lock()
		defer gw.Unlock()

		// redraw everything
		newbuf := ""
		for _, msg := range gw.messages {
			newbuf += gw.formatMessage(msg) + "\n"
		}

		messageView.Clear()
		fmt.Fprint(messageView, newbuf)
		return nil
	})
}

func (gw *guiwrapper) addMessage(m guimessage) {

	gw.Lock()
	// only keep maxlines lines in memory
	delta := len(gw.messages) - gw.maxlines
	if delta > 0 {
		gw.messages = append(gw.messages[delta:], &m)
	} else {
		gw.messages = append(gw.messages, &m)
	}
	gw.Unlock()
	gw.redraw()
}

//currently not in use
func (gw *guiwrapper) applyTag(tag string, nick string) {

	gw.Lock()
	defer gw.Unlock()

	for _, m := range gw.messages {
		if m.nick != "" && strings.EqualFold(m.nick, nick) {
			m.tag = tag
		}
	}
}