Merge branch 'deep-message-rendering'

1 files changed, 411 insertions, 0 deletions

diff --git a/ui/messages/htmlmessage.go b/ui/messages/htmlmessage.go
new file mode 100644
index 0000000..8685442
--- /dev/null
+++ b/ui/messages/htmlmessage.go
@@ -0,0 +1,411 @@
+// 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 (
+	"fmt"
+	"math"
+	"strings"
+	"time"
+
+	"github.com/mattn/go-runewidth"
+
+	"maunium.net/go/mautrix"
+	"maunium.net/go/mauview"
+	"maunium.net/go/tcell"
+
+	"maunium.net/go/gomuks/config"
+	"maunium.net/go/gomuks/ui/widget"
+)
+
+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) {
+	if width <= 0 {
+		panic("Negative width in CalculateBuffer")
+	}
+	// 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 hw.Root.PlainText()
+}
+
+func (hw *HTMLMessage) NotificationContent() string {
+	return hw.Root.PlainText()
+}
+
+type AdjustStyleFunc func(tcell.Style) tcell.Style
+
+type HTMLEntity interface {
+	AdjustStyle(AdjustStyleFunc) HTMLEntity
+	Draw(screen mauview.Screen)
+	IsBlock() bool
+	GetTag() string
+	PlainText() string
+	String() string
+	Height() int
+
+	calculateBuffer(width, startX int, bare bool) int
+	getStartX() int
+}
+
+type BlockquoteEntity struct {
+	*BaseHTMLEntity
+}
+
+func NewBlockquoteEntity(children []HTMLEntity) *BlockquoteEntity {
+	return &BlockquoteEntity{&BaseHTMLEntity{
+		Tag:      "blockquote",
+		Children: children,
+		Block:    true,
+		Indent:   2,
+	}}
+}
+
+func (be *BlockquoteEntity) Draw(screen mauview.Screen) {
+	be.BaseHTMLEntity.Draw(screen)
+	for y := 0; y < be.height; y++ {
+		screen.SetContent(0, y, '>', nil, be.Style)
+	}
+}
+
+func (be *BlockquoteEntity) String() string {
+	return fmt.Sprintf("&BlockquoteEntity{%s},\n", be.BaseHTMLEntity)
+}
+
+type ListEntity struct {
+	*BaseHTMLEntity
+	Ordered bool
+	Start   int
+}
+
+func digits(num int) int {
+	if num <= 0 {
+		return 0
+	}
+	return int(math.Floor(math.Log10(float64(num))) + 1)
+}
+
+func NewListEntity(ordered bool, start int, children []HTMLEntity) *ListEntity {
+	entity := &ListEntity{
+		BaseHTMLEntity: &BaseHTMLEntity{
+			Tag:      "ul",
+			Children: children,
+			Block:    true,
+			Indent:   2,
+		},
+		Ordered: ordered,
+		Start:   start,
+	}
+	if ordered {
+		entity.Tag = "ol"
+		entity.Indent += digits(start + len(children) - 1)
+	}
+	return entity
+}
+
+func (le *ListEntity) Draw(screen mauview.Screen) {
+	width, _ := screen.Size()
+
+	proxyScreen := &mauview.ProxyScreen{Parent: screen, OffsetX: le.Indent, Width: width - le.Indent}
+	for i, entity := range le.Children {
+		proxyScreen.Height = entity.Height()
+		if le.Ordered {
+			number := le.Start + i
+			line := fmt.Sprintf("%d. %s", number, strings.Repeat(" ", le.Indent-2-digits(number)))
+			widget.WriteLine(screen, mauview.AlignLeft, line, 0, proxyScreen.OffsetY, le.Indent, le.Style)
+		} else {
+			screen.SetContent(0, proxyScreen.OffsetY, '●', nil, le.Style)
+		}
+		entity.Draw(proxyScreen)
+		proxyScreen.OffsetY += entity.Height()
+	}
+}
+
+func (le *ListEntity) String() string {
+	return fmt.Sprintf("&ListEntity{Ordered=%t, Start=%d, Base=%s},\n", le.Ordered, le.Start, le.BaseHTMLEntity)
+}
+
+type BreakEntity struct {
+	*BaseHTMLEntity
+}
+
+func NewBreakEntity() *BreakEntity {
+	return &BreakEntity{&BaseHTMLEntity{
+		Tag:   "br",
+		Block: true,
+	}}
+}
+
+type BaseHTMLEntity struct {
+	// Permanent variables
+	Tag      string
+	Text     string
+	Style    tcell.Style
+	Children []HTMLEntity
+	Block    bool
+	Indent   int
+
+	DefaultHeight int
+
+	// Non-permanent variables (calculated buffer data)
+	buffer    []string
+	prevWidth int
+	startX    int
+	height    int
+}
+
+func NewHTMLTextEntity(text string) *BaseHTMLEntity {
+	return &BaseHTMLEntity{
+		Tag:  "text",
+		Text: text,
+	}
+}
+
+func NewHTMLEntity(tag string, children []HTMLEntity, block bool) *BaseHTMLEntity {
+	return &BaseHTMLEntity{
+		Tag:      tag,
+		Children: children,
+		Block:    block,
+	}
+}
+
+func (he *BaseHTMLEntity) AdjustStyle(fn AdjustStyleFunc) HTMLEntity {
+	for _, child := range he.Children {
+		child.AdjustStyle(fn)
+	}
+	he.Style = fn(he.Style)
+	return he
+}
+
+func (he *BaseHTMLEntity) IsBlock() bool {
+	return he.Block
+}
+
+func (he *BaseHTMLEntity) GetTag() string {
+	return he.Tag
+}
+
+func (he *BaseHTMLEntity) Height() int {
+	return he.height
+}
+
+func (he *BaseHTMLEntity) getStartX() int {
+	return he.startX
+}
+
+func (he *BaseHTMLEntity) String() string {
+	var buf strings.Builder
+	buf.WriteString("&BaseHTMLEntity{\n")
+	_, _ = fmt.Fprintf(&buf, `    Tag="%s", Style=%d, Block=%t, Indent=%d, startX=%d, height=%d,`,
+		he.Tag, he.Style, he.Block, he.Indent, he.startX, he.height)
+	buf.WriteRune('\n')
+	_, _ = fmt.Fprintf(&buf, `    Buffer=["%s"]`, strings.Join(he.buffer, "\", \""))
+	if len(he.Text) > 0 {
+		buf.WriteString(",\n")
+		_, _ = fmt.Fprintf(&buf, `    Text="%s"`, he.Text)
+	}
+	if len(he.Children) > 0 {
+		buf.WriteString(",\n")
+		buf.WriteString("    Children={")
+		for _, child := range he.Children {
+			buf.WriteString("\n        ")
+			buf.WriteString(strings.Join(strings.Split(strings.TrimRight(child.String(), "\n"), "\n"), "\n        "))
+		}
+		buf.WriteString("\n    },")
+	}
+	buf.WriteString("\n},\n")
+	return buf.String()
+}
+
+func (he *BaseHTMLEntity) PlainText() string {
+	if len(he.Children) == 0 {
+		return he.Text
+	}
+	var buf strings.Builder
+	buf.WriteString(he.Text)
+	newlined := false
+	for _, child := range he.Children {
+		if child.IsBlock() && !newlined {
+			buf.WriteRune('\n')
+		}
+		newlined = false
+		buf.WriteString(child.PlainText())
+		if child.IsBlock() {
+			buf.WriteRune('\n')
+			newlined = true
+		}
+	}
+	return buf.String()
+}
+
+func (he *BaseHTMLEntity) 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 {
+		prevBreak := false
+		proxyScreen := &mauview.ProxyScreen{Parent: screen, OffsetX: he.Indent, Width: width - he.Indent}
+		for i, entity := range he.Children {
+			if i != 0 && entity.getStartX() == 0 {
+				proxyScreen.OffsetY++
+			}
+			proxyScreen.Height = entity.Height()
+			entity.Draw(proxyScreen)
+			proxyScreen.OffsetY += entity.Height() - 1
+			_, isBreak := entity.(*BreakEntity)
+			if prevBreak && isBreak {
+				proxyScreen.OffsetY++
+			}
+			prevBreak = isBreak
+		}
+	}
+}
+
+func (he *BaseHTMLEntity) calculateBuffer(width, startX int, bare bool) int {
+	he.startX = startX
+	if he.Block {
+		he.startX = 0
+	}
+	he.height = 0
+	if len(he.Children) > 0 {
+		childStartX := he.startX
+		prevBreak := false
+		for _, entity := range he.Children {
+			if entity.IsBlock() || childStartX == 0 || he.height == 0 {
+				he.height++
+			}
+			childStartX = entity.calculateBuffer(width-he.Indent, childStartX, bare)
+			he.height += entity.Height() - 1
+			_, isBreak := entity.(*BreakEntity)
+			if prevBreak && isBreak {
+				he.height++
+			}
+			prevBreak = isBreak
+		}
+		if len(he.Text) == 0 && !he.Block {
+			return childStartX
+		}
+	}
+	if len(he.Text) > 0 {
+		he.prevWidth = width
+		if he.buffer == nil {
+			he.buffer = []string{}
+		}
+		bufPtr := 0
+		text := he.Text
+		textStartX := he.startX
+		for {
+			// TODO add option no wrap and character wrap options
+			extract := runewidth.Truncate(text, width-textStartX, "")
+			extract, wordWrapped := trim(extract, text, bare)
+			if !wordWrapped && textStartX > 0 {
+				if bufPtr < len(he.buffer) {
+					he.buffer[bufPtr] = ""
+				} else {
+					he.buffer = append(he.buffer, "")
+				}
+				bufPtr++
+				textStartX = 0
+				continue
+			}
+			if bufPtr < len(he.buffer) {
+				he.buffer[bufPtr] = extract
+			} else {
+				he.buffer = append(he.buffer, extract)
+			}
+			bufPtr++
+			text = text[len(extract):]
+			if len(text) == 0 {
+				he.buffer = he.buffer[:bufPtr]
+				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 textStartX + runewidth.StringWidth(extract)
+			}
+			textStartX = 0
+		}
+	}
+	if len(he.Text) == 0 && len(he.Children) == 0 {
+		he.height = he.DefaultHeight
+	}
+	return he.startX
+}
+
+func trim(extract, full string, bare bool) (string, bool) {
+	if len(extract) == len(full) {
+		return extract, true
+	}
+	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, true
+			}
+		}
+	}
+	return extract, len(extract) > 0 && extract[len(extract)-1] == ' '
+}