Fix event collapsing

2 files changed, 93 insertions, 73 deletions

diff --git a/app.go b/app.go
index 9fd9b1a..086ba0c 100644
--- a/app.go
+++ b/app.go
@@ -990,7 +990,7 @@ func (app *App) formatEvent(ev irc.Event) ui.Line {
 			HeadColor: tcell.ColorGray,
 			Body:      body.StyledString(),
 			Mergeable: true,
-			Data:      []interface{}{ev},
+			Data:      []irc.Event{ev},
 		}
 	case irc.UserJoinEvent:
 		var body ui.StyledStringBuilder
@@ -1005,7 +1005,7 @@ func (app *App) formatEvent(ev irc.Event) ui.Line {
 			HeadColor: tcell.ColorGray,
 			Body:      body.StyledString(),
 			Mergeable: true,
-			Data:      []interface{}{ev},
+			Data:      []irc.Event{ev},
 		}
 	case irc.UserPartEvent:
 		var body ui.StyledStringBuilder
@@ -1020,7 +1020,7 @@ func (app *App) formatEvent(ev irc.Event) ui.Line {
 			HeadColor: tcell.ColorGray,
 			Body:      body.StyledString(),
 			Mergeable: true,
-			Data:      []interface{}{ev},
+			Data:      []irc.Event{ev},
 		}
 	case irc.UserQuitEvent:
 		var body ui.StyledStringBuilder
@@ -1035,7 +1035,7 @@ func (app *App) formatEvent(ev irc.Event) ui.Line {
 			HeadColor: tcell.ColorGray,
 			Body:      body.StyledString(),
 			Mergeable: true,
-			Data:      []interface{}{ev},
+			Data:      []irc.Event{ev},
 		}
 	case irc.TopicChangeEvent:
 		topic := ui.IRCString(ev.Topic).String()
@@ -1048,13 +1048,15 @@ func (app *App) formatEvent(ev irc.Event) ui.Line {
 		}
 	case irc.ModeChangeEvent:
 		body := fmt.Sprintf("[%s]", ev.Mode)
+		// simple mode event: <+/-><mode> <nick>
+		mergeable := len(strings.Split(ev.Mode, " ")) == 2
 		return ui.Line{
 			At:        ev.Time,
 			Head:      "--",
 			HeadColor: tcell.ColorGray,
 			Body:      ui.Styled(body, tcell.StyleDefault.Foreground(tcell.ColorGray)),
-			Mergeable: true,
-			Data:      []interface{}{ev},
+			Mergeable: mergeable,
+			Data:      []irc.Event{ev},
 		}
 	default:
 		return ui.Line{}
@@ -1139,86 +1141,104 @@ func (app *App) formatMessage(s *irc.Session, ev irc.MessageEvent) (buffer strin
 }
 
 func (app *App) mergeLine(former *ui.Line, addition ui.Line) {
-	partQuitUser := func(ev interface{}) string {
-		if ev, ok := ev.(irc.UserQuitEvent); ok {
-			return ev.User
-		}
-		if ev, ok := ev.(irc.UserPartEvent); ok {
-			return ev.User
-		}
-		panic("unreachable")
+	events := append(former.Data.([]irc.Event), addition.Data.([]irc.Event)...)
+	type flow struct {
+		hide  bool
+		state int // -1: newly offline; 1: newly online
 	}
+	flows := make(map[string]*flow)
+
+	eventFlows := make([]*flow, len(events))
 
-	changed := false
-Outer:
-	for _, addedEvent := range addition.Data {
-		switch addedEvent := addedEvent.(type) {
+	for i, ev := range events {
+		switch ev := ev.(type) {
 		case irc.UserNickEvent:
-			for i := len(former.Data) - 1; i >= 0; i-- {
-				switch ev := former.Data[i].(type) {
-				case irc.UserNickEvent:
-					if ev.User == addedEvent.FormerNick && ev.FormerNick == addedEvent.User {
-						former.Data = append(former.Data[:i], former.Data[i+1:]...)
-						changed = true
-						continue Outer
-					}
-				}
+			userCf := strings.ToLower(ev.User)
+			f, ok := flows[strings.ToLower(ev.FormerNick)]
+			if ok {
+				flows[userCf] = f
+				delete(flows, strings.ToLower(ev.FormerNick))
+				eventFlows[i] = f
+			} else {
+				f = &flow{}
+				flows[userCf] = f
+				eventFlows[i] = f
 			}
 		case irc.UserJoinEvent:
-			for i := len(former.Data) - 1; i >= 0; i-- {
-				switch ev := former.Data[i].(type) {
-				case irc.UserPartEvent, irc.UserQuitEvent:
-					if partQuitUser(ev) == addedEvent.User {
-						former.Data = append(former.Data[:i], former.Data[i+1:]...)
-						changed = true
-						continue Outer
-					}
+			userCf := strings.ToLower(ev.User)
+			f, ok := flows[userCf]
+			if ok {
+				if f.state == -1 {
+					f.hide = true
+					delete(flows, userCf)
+				}
+			} else {
+				f = &flow{
+					state: 1,
+				}
+				flows[userCf] = f
+				eventFlows[i] = f
+			}
+		case irc.UserPartEvent:
+			userCf := strings.ToLower(ev.User)
+			f, ok := flows[userCf]
+			if ok {
+				if f.state == 1 {
+					f.hide = true
+					delete(flows, userCf)
 				}
+			} else {
+				f = &flow{
+					state: -1,
+				}
+				flows[userCf] = f
+				eventFlows[i] = f
 			}
-		case irc.UserQuitEvent, irc.UserPartEvent:
-			user := partQuitUser(addedEvent)
-			var toRemove []int
-			for i := len(former.Data) - 1; i >= 0; i-- {
-				switch ev := former.Data[i].(type) {
-				case irc.UserNickEvent:
-					if ev.User == user {
-						user = ev.FormerNick
-						toRemove = append(toRemove, i)
-					}
-				case irc.UserJoinEvent:
-					if ev.User == user {
-						for _, i := range append(toRemove, i) {
-							former.Data = append(former.Data[:i], former.Data[i+1:]...)
-						}
-						changed = true
-						continue Outer
-					}
+		case irc.UserQuitEvent:
+			userCf := strings.ToLower(ev.User)
+			f, ok := flows[userCf]
+			if ok {
+				if f.state == 1 {
+					f.hide = true
+					delete(flows, userCf)
+				}
+			} else {
+				f = &flow{
+					state: -1,
 				}
+				flows[userCf] = f
+				eventFlows[i] = f
+			}
+		case irc.ModeChangeEvent:
+			userCf := strings.ToLower(strings.Split(ev.Mode, " ")[1])
+			f, ok := flows[userCf]
+			if ok {
+				eventFlows[i] = f
+			} else {
+				f = &flow{}
+				flows[userCf] = f
+				eventFlows[i] = f
 			}
 		}
-		former.Data = append(former.Data, addedEvent)
 	}
-	if changed {
-		if len(former.Data) == 0 {
-			former.Body = ui.PlainString("")
-			return
+
+	newBody := new(ui.StyledStringBuilder)
+	newBody.Grow(128)
+	first := true
+	for i, ev := range events {
+		if f := eventFlows[i]; f == nil || f.hide {
+			continue
 		}
-		var body ui.StyledStringBuilder
-		body.Grow(len(former.Body.String()))
-		body.WriteStyledString(app.formatEvent(former.Data[0]).Body)
-		for _, ev := range former.Data[1:] {
-			body.WriteString("  ")
-			body.WriteStyledString(app.formatEvent(ev).Body)
+		l := app.formatEvent(ev)
+		if first {
+			first = false
+		} else {
+			newBody.WriteString("  ")
 		}
-		former.Body = body.StyledString()
-	} else {
-		var newBody ui.StyledStringBuilder
-		newBody.Grow(len(former.Body.String()) + 2 + len(addition.Body.String()))
-		newBody.WriteStyledString(former.Body)
-		newBody.WriteString("  ")
-		newBody.WriteStyledString(addition.Body)
-		former.Body = newBody.StyledString()
+		newBody.WriteStyledString(l.Body)
 	}
+	former.Body = newBody.StyledString()
+	former.Data = events
 }
 
 // updatePrompt changes the prompt text according to the application context.
diff --git a/ui/buffers.go b/ui/buffers.go
index 4c40e19..6222fbe 100644
--- a/ui/buffers.go
+++ b/ui/buffers.go
@@ -33,7 +33,7 @@ type Line struct {
 	HeadColor tcell.Color
 	Highlight bool
 	Mergeable bool
-	Data      []interface{}
+	Data      interface{}
 
 	splitPoints []point
 	width       int