hicli: add support for sending markdown and rainbows

format/mdext/rainbow/goldmark.go

@@ -0,0 +1,120 @@
+// Copyright (c) 2024 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package rainbow
+
+import (
+	"fmt"
+	"unicode"
+
+	"github.com/rivo/uniseg"
+	"github.com/yuin/goldmark"
+	"github.com/yuin/goldmark/ast"
+	"github.com/yuin/goldmark/renderer"
+	"github.com/yuin/goldmark/renderer/html"
+	"github.com/yuin/goldmark/util"
+	"go.mau.fi/util/random"
+)
+
+// Extension is a goldmark extension that adds rainbow text coloring to the HTML renderer.
+var Extension = &extRainbow{}
+
+type extRainbow struct{}
+type rainbowRenderer struct {
+	HardWraps bool
+	ColorID   string
+}
+
+var defaultRB = &rainbowRenderer{HardWraps: true, ColorID: random.String(16)}
+
+func (er *extRainbow) Extend(m goldmark.Markdown) {
+	m.Renderer().AddOptions(renderer.WithNodeRenderers(util.Prioritized(defaultRB, 0)))
+}
+
+func (rb *rainbowRenderer) RegisterFuncs(reg renderer.NodeRendererFuncRegisterer) {
+	reg.Register(ast.KindText, rb.renderText)
+	reg.Register(ast.KindString, rb.renderString)
+}
+
+type rainbowBufWriter struct {
+	util.BufWriter
+	ColorID string
+}
+
+func (rbw rainbowBufWriter) WriteString(s string) (int, error) {
+	i := 0
+	graphemes := uniseg.NewGraphemes(s)
+	for graphemes.Next() {
+		runes := graphemes.Runes()
+		if len(runes) == 1 && unicode.IsSpace(runes[0]) {
+			i2, err := rbw.BufWriter.WriteRune(runes[0])
+			i += i2
+			if err != nil {
+				return i, err
+			}
+			continue
+		}
+		i2, err := fmt.Fprintf(rbw.BufWriter, "<font color=\"%s\">%s</font>", rbw.ColorID, graphemes.Str())
+		i += i2
+		if err != nil {
+			return i, err
+		}
+	}
+	return i, nil
+}
+
+func (rbw rainbowBufWriter) Write(data []byte) (int, error) {
+	return rbw.WriteString(string(data))
+}
+
+func (rbw rainbowBufWriter) WriteByte(c byte) error {
+	_, err := rbw.WriteRune(rune(c))
+	return err
+}
+
+func (rbw rainbowBufWriter) WriteRune(r rune) (int, error) {
+	if unicode.IsSpace(r) {
+		return rbw.BufWriter.WriteRune(r)
+	} else {
+		return fmt.Fprintf(rbw.BufWriter, "<font color=\"%s\">%c</font>", rbw.ColorID, r)
+	}
+}
+
+func (rb *rainbowRenderer) renderText(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+	if !entering {
+		return ast.WalkContinue, nil
+	}
+	n := node.(*ast.Text)
+	segment := n.Segment
+	if n.IsRaw() {
+		html.DefaultWriter.RawWrite(rainbowBufWriter{w, rb.ColorID}, segment.Value(source))
+	} else {
+		html.DefaultWriter.Write(rainbowBufWriter{w, rb.ColorID}, segment.Value(source))
+		if n.HardLineBreak() || (n.SoftLineBreak() && rb.HardWraps) {
+			_, _ = w.WriteString("<br>\n")
+		} else if n.SoftLineBreak() {
+			_ = w.WriteByte('\n')
+		}
+	}
+	return ast.WalkContinue, nil
+}
+
+func (rb *rainbowRenderer) renderString(w util.BufWriter, source []byte, node ast.Node, entering bool) (ast.WalkStatus, error) {
+	if !entering {
+		return ast.WalkContinue, nil
+	}
+	n := node.(*ast.String)
+	if n.IsCode() {
+		_, _ = w.Write(n.Value)
+	} else {
+		if n.IsRaw() {
+			html.DefaultWriter.RawWrite(rainbowBufWriter{w, rb.ColorID}, n.Value)
+		} else {
+			html.DefaultWriter.Write(rainbowBufWriter{w, rb.ColorID}, n.Value)
+		}
+	}
+	return ast.WalkContinue, nil
+}

format/mdext/rainbow/gradient.go

@@ -0,0 +1,56 @@
+// Copyright (c) 2024 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package rainbow
+
+import (
+	"regexp"
+	"strings"
+
+	"github.com/lucasb-eyer/go-colorful"
+)
+
+// GradientTable from https://github.com/lucasb-eyer/go-colorful/blob/master/doc/gradientgen/gradientgen.go
+type GradientTable []struct {
+	Col colorful.Color
+	Pos float64
+}
+
+func (gt GradientTable) GetInterpolatedColorFor(t float64) colorful.Color {
+	for i := 0; i < len(gt)-1; i++ {
+		c1 := gt[i]
+		c2 := gt[i+1]
+		if c1.Pos <= t && t <= c2.Pos {
+			t := (t - c1.Pos) / (c2.Pos - c1.Pos)
+			return c1.Col.BlendHcl(c2.Col, t).Clamped()
+		}
+	}
+	return gt[len(gt)-1].Col
+}
+
+var Gradient = GradientTable{
+	{colorful.LinearRgb(1, 0, 0), 0 / 11.0},
+	{colorful.LinearRgb(1, 0.5, 0), 1 / 11.0},
+	{colorful.LinearRgb(1, 1, 0), 2 / 11.0},
+	{colorful.LinearRgb(0.5, 1, 0), 3 / 11.0},
+	{colorful.LinearRgb(0, 1, 0), 4 / 11.0},
+	{colorful.LinearRgb(0, 1, 0.5), 5 / 11.0},
+	{colorful.LinearRgb(0, 1, 1), 6 / 11.0},
+	{colorful.LinearRgb(0, 0.5, 1), 7 / 11.0},
+	{colorful.LinearRgb(0, 0, 1), 8 / 11.0},
+	{colorful.LinearRgb(0.5, 0, 1), 9 / 11.0},
+	{colorful.LinearRgb(1, 0, 1), 10 / 11.0},
+	{colorful.LinearRgb(1, 0, 0.5), 11 / 11.0},
+}
+
+func ApplyColor(htmlBody string) string {
+	count := strings.Count(htmlBody, defaultRB.ColorID)
+	i := -1
+	return regexp.MustCompile(defaultRB.ColorID).ReplaceAllStringFunc(htmlBody, func(match string) string {
+		i++
+		return Gradient.GetInterpolatedColorFor(float64(i) / float64(count)).Hex()
+	})
+}

go.mod

@@ -10,7 +10,9 @@ require (
 	github.com/gorilla/mux v1.8.0
 	github.com/gorilla/websocket v1.5.0
 	github.com/lib/pq v1.10.9
+	github.com/lucasb-eyer/go-colorful v1.2.0
 	github.com/mattn/go-sqlite3 v1.14.23
+	github.com/rivo/uniseg v0.4.7
 	github.com/rs/xid v1.6.0
 	github.com/rs/zerolog v1.33.0
 	github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e

go.sum

@@ -19,6 +19,8 @@ github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWm
 github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
 github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
+github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
+github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
@@ -31,6 +33,8 @@ github.com/petermattis/goid v0.0.0-20240813172612-4fcff4a6cae7/go.mod h1:pxMtw7c
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
+github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
 github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
 github.com/rs/xid v1.6.0 h1:fV591PaemRlL6JfRxGDEPl69wICngIQ3shQtzfy2gxU=
 github.com/rs/xid v1.6.0/go.mod h1:7XoLgs4eV+QndskICGsho+ADou8ySMSjJKDIan90Nz0=

hicli/json-commands.go

@@ -38,7 +38,11 @@ func (h *HiClient) handleJSONCommand(ctx context.Context, req *JSONCommand) (any
 			return true, nil
 		})
 	case "send_message":
-		return unmarshalAndCall(req.Data, func(params *sendParams) (*database.Event, error) {
+		return unmarshalAndCall(req.Data, func(params *sendMessageParams) (*database.Event, error) {
+			return h.SendMessage(ctx, params.RoomID, params.Text, params.MediaPath)
+		})
+	case "send_event":
+		return unmarshalAndCall(req.Data, func(params *sendEventParams) (*database.Event, error) {
 			return h.Send(ctx, params.RoomID, params.EventType, params.Content)
 		})
 	case "get_event":
@@ -100,7 +104,13 @@ type cancelRequestParams struct {
 	Reason    string `json:"reason"`
 }
 
-type sendParams struct {
+type sendMessageParams struct {
+	RoomID    id.RoomID `json:"room_id"`
+	Text      string    `json:"text"`
+	MediaPath string    `json:"media_path"`
+}
+
+type sendEventParams struct {
 	RoomID    id.RoomID       `json:"room_id"`
 	EventType event.Type      `json:"type"`
 	Content   json.RawMessage `json:"content"`

hicli/send.go

@@ -11,17 +11,43 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"strings"
 	"time"
 
 	"github.com/rs/zerolog"
+	"github.com/yuin/goldmark"
 
 	"maunium.net/go/mautrix"
 	"maunium.net/go/mautrix/crypto"
 	"maunium.net/go/mautrix/event"
+	"maunium.net/go/mautrix/format"
+	"maunium.net/go/mautrix/format/mdext/rainbow"
 	"maunium.net/go/mautrix/hicli/database"
 	"maunium.net/go/mautrix/id"
 )
 
+var (
+	rainbowWithHTML = goldmark.New(format.Extensions, format.HTMLOptions, goldmark.WithExtensions(rainbow.Extension))
+)
+
+func (h *HiClient) SendMessage(ctx context.Context, roomID id.RoomID, text, mediaPath string) (*database.Event, error) {
+	var content event.MessageEventContent
+	if strings.HasPrefix(text, "/rainbow ") {
+		text = strings.TrimPrefix(text, "/rainbow ")
+		content = format.RenderMarkdownCustom(text, rainbowWithHTML)
+		content.FormattedBody = rainbow.ApplyColor(content.FormattedBody)
+	} else if strings.HasPrefix(text, "/plain ") {
+		text = strings.TrimPrefix(text, "/plain ")
+		content = format.RenderMarkdown(text, false, false)
+	} else if strings.HasPrefix(text, "/html ") {
+		text = strings.TrimPrefix(text, "/html ")
+		content = format.RenderMarkdown(text, false, true)
+	} else {
+		content = format.RenderMarkdown(text, true, false)
+	}
+	return h.Send(ctx, roomID, event.EventMessage, &content)
+}
+
 func (h *HiClient) Send(ctx context.Context, roomID id.RoomID, evtType event.Type, content any) (*database.Event, error) {
 	roomMeta, err := h.DB.Room.Get(ctx, roomID)
 	if err != nil {