1 files changed, 187 insertions, 0 deletions
diff --git a/ui/messages/htmlmessage.go b/ui/messages/htmlmessage.go
new file mode 100644
index 0000000..de4b30c
--- /dev/null
+++ b/ui/messages/htmlmessage.go
@@ -0,0 +1,187 @@
+// gomuks - A terminal Matrix client written in Go.
+// Copyright (C) 2019 Tulir Asokan
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package messages
+
+import (
+	"time"
+
+	"github.com/mattn/go-runewidth"
+
+	"maunium.net/go/gomuks/config"
+	"maunium.net/go/gomuks/ui/widget"
+	"maunium.net/go/mautrix"
+	"maunium.net/go/mauview"
+	"maunium.net/go/tcell"
+)
+
+type HTMLMessage struct {
+	BaseMessage
+
+	Root *HTMLEntity
+}
+
+func NewHTMLMessage(id, sender, displayname string, msgtype mautrix.MessageType, root *HTMLEntity, timestamp time.Time) UIMessage {
+	return &HTMLMessage{
+		BaseMessage: newBaseMessage(id, sender, displayname, msgtype, timestamp),
+		Root:        root,
+	}
+}
+func (hw *HTMLMessage) Draw(screen mauview.Screen) {
+	hw.Root.Draw(screen)
+}
+
+func (hw *HTMLMessage) OnKeyEvent(event mauview.KeyEvent) bool {
+	return false
+}
+
+func (hw *HTMLMessage) OnMouseEvent(event mauview.MouseEvent) bool {
+	return false
+}
+
+func (hw *HTMLMessage) OnPasteEvent(event mauview.PasteEvent) bool {
+	return false
+}
+
+func (hw *HTMLMessage) CalculateBuffer(preferences config.UserPreferences, width int) {
+	// TODO account for bare messages in initial startX
+	startX := 0
+	hw.Root.calculateBuffer(width, startX, preferences.BareMessageView)
+}
+
+func (hw *HTMLMessage) Height() int {
+	return hw.Root.height
+}
+
+func (hw *HTMLMessage) PlainText() string {
+	return "Plaintext unavailable"
+}
+
+func (hw *HTMLMessage) NotificationContent() string {
+	return "Notification content unavailable"
+}
+
+type HTMLEntity struct {
+	// Permanent variables
+	Tag      string
+	Text     string
+	Style    tcell.Style
+	Children []*HTMLEntity
+	Block    bool
+	Indent   int
+
+	// Non-permanent variables (calculated buffer data)
+	buffer    []string
+	prevWidth int
+	startX    int
+	height    int
+}
+
+func (he *HTMLEntity) AdjustStyle(fn func(tcell.Style) tcell.Style) *HTMLEntity {
+	for _, child := range he.Children {
+		child.AdjustStyle(fn)
+	}
+	he.Style = fn(he.Style)
+	return he
+}
+
+func (he *HTMLEntity) Draw(screen mauview.Screen) {
+	width, _ := screen.Size()
+	if len(he.buffer) > 0 {
+		x := he.startX
+		for y, line := range he.buffer {
+			widget.WriteLine(screen, mauview.AlignLeft, line, x, y, width, he.Style)
+			x = 0
+		}
+	}
+	if len(he.Children) > 0 {
+		proxyScreen := &mauview.ProxyScreen{Parent: screen, OffsetX: he.Indent, Width: width - he.Indent}
+		for _, entity := range he.Children {
+			if entity.Block {
+				proxyScreen.OffsetY++
+			}
+			proxyScreen.Height = entity.height
+			entity.Draw(proxyScreen)
+			proxyScreen.OffsetY += entity.height - 1
+		}
+	}
+}
+
+func (he *HTMLEntity) calculateBuffer(width, startX int, bare bool) int {
+	if len(he.Children) > 0 {
+		childStartX := 0
+		for _, entity := range he.Children {
+			childStartX = entity.calculateBuffer(width-he.Indent, childStartX, bare)
+			he.height += entity.height - 1
+		}
+	}
+	if len(he.Text) > 0 && width != he.prevWidth {
+		he.prevWidth = width
+		he.buffer = make([]string, 0, 1)
+		text := he.Text
+		if !he.Block {
+			he.startX = startX
+		} else {
+			startX = 0
+		}
+		for {
+			extract := runewidth.Truncate(text, width-startX, "")
+			extract = trim(extract, text, bare)
+			he.buffer = append(he.buffer, extract)
+			text = text[len(extract):]
+			startX = 0
+			if len(text) == 0 {
+				he.height += len(he.buffer)
+				// This entity is over, return the startX for the next entity
+				if he.Block {
+					// ...except if it's a block entity
+					return 0
+				}
+				return runewidth.StringWidth(extract)
+			}
+		}
+	}
+	return 0
+}
+
+// Regular expressions used to split lines when calculating the buffer.
+/*var (
+	boundaryPattern     = regexp.MustCompile(`([[:punct:]]\s*|\s+)`)
+	bareBoundaryPattern = regexp.MustCompile(`(\s+)`)
+	spacePattern        = regexp.MustCompile(`\s+`)
+)*/
+
+func trim(extract, full string, bare bool) string {
+	if len(extract) == len(full) {
+		return extract
+	}
+	if spaces := spacePattern.FindStringIndex(full[len(extract):]); spaces != nil && spaces[0] == 0 {
+		extract = full[:len(extract)+spaces[1]]
+	}
+	regex := boundaryPattern
+	if bare {
+		regex = bareBoundaryPattern
+	}
+	matches := regex.FindAllStringIndex(extract, -1)
+	if len(matches) > 0 {
+		if match := matches[len(matches)-1]; len(match) >= 2 {
+			if until := match[1]; until < len(extract) {
+				extract = extract[:until]
+			}
+		}
+	}
+	return extract
+}