Split slides first before rendering them

- add some more config options
- cleanup code
- remove state machine

api/views.go

@@ -1,13 +1,9 @@
 package api
 
 import (
-	"hash/fnv"
 	"io"
 
 	"github.com/gofiber/fiber/v2"
-	"github.com/gomarkdown/markdown"
-	"github.com/gomarkdown/markdown/html"
-	"github.com/gomarkdown/markdown/parser"
 	"go.uber.org/multierr"
 
 	"github.com/baez90/goveal/config"
@@ -15,13 +11,6 @@ import (
 	"github.com/baez90/goveal/rendering"
 )
 
-const (
-	parserExtensions = parser.NoIntraEmphasis | parser.Tables | parser.FencedCode |
-		parser.Autolink | parser.Strikethrough | parser.SpaceHeadings | parser.HeadingIDs |
-		parser.BackslashLineBreak | parser.DefinitionLists | parser.MathJax | parser.Titleblock |
-		parser.OrderedListStart | parser.Attributes
-)
-
 type Views struct {
 	cfg        *config.Components
 	wdfs       fs.FS
@@ -54,20 +43,14 @@ func (p *Views) RenderedMarkdown(ctx *fiber.Ctx) (err error) {
 		return err
 	}
 
-	mdParser := parser.NewWithExtensions(parserExtensions)
-	rr := &rendering.RevealRenderer{
-		StateMachine: rendering.NewStateMachine("***", "---"),
-		Hash:         fnv.New32a(),
-	}
-	renderer := html.NewRenderer(html.RendererOptions{
-		Flags:          html.CommonFlags | html.HrefTargetBlank,
-		RenderNodeHook: rr.RenderHook,
-	})
-
-	ctx.Append(fiber.HeaderContentType, fiber.MIMETextHTML)
-	if _, err = ctx.Write(markdown.ToHTML(data, mdParser, renderer)); err != nil {
+	var rendered []byte
+	if rendered, err = rendering.ToHTML(string(data), p.cfg.Rendering); err != nil {
+		return err
+	} else if _, err = ctx.Write(rendered); err != nil {
 		return err
 	}
 
+	ctx.Append(fiber.HeaderContentType, fiber.MIMETextHTML)
+
 	return err
 }

config/components.go

@@ -13,6 +13,10 @@ var defaults = map[string]interface{}{
 	"slideNumber":                         true,
 	"menu.numbers":                        true,
 	"menu.useTextContentForMissingTitles": true,
+	"menu.transitions":                    true,
+	"menu.hideMissingTitles":              true,
+	"menu.markers":                        true,
+	"menu.openButton":                     true,
 }
 
 const (
@@ -51,7 +55,10 @@ type (
 		Menu           struct {
 			Numbers                        bool `json:"numbers"`
 			UseTextContentForMissingTitles bool `json:"useTextContentForMissingTitles"`
-			Transitions                    bool
+			Transitions                    bool `json:"transitions"`
+			HideMissingTitles              bool `json:"hideMissingTitles"`
+			Markers                        bool `json:"markers"`
+			OpenButton                     bool `json:"openButton"`
 		} `json:"menu"`
 	}
 	Components struct {

examples/goveal.yaml

@@ -1,7 +1,7 @@
 theme: night
 codeTheme: monokai
-horizontalSeparator: ===
-verticalSeparator: ---
+horizontalSeparator: ---
+verticalSeparator: '\*\*\*'
 transition: convex
 controlsLayout: edges
 controls: true
@@ -12,6 +12,10 @@ slideNumber: true
 menu:
   numbers: false
   useTextContentForMissingTitles: true
+  transitions: true
+  hideMissingTitles: false
+  markers: true
+  openButton: true
 mermaid:
   theme: forest
 stylesheets:

examples/slides.md

@@ -91,6 +91,7 @@ for (var j = 0; j < i; j++) {
 ### Mermaid
 
 ```mermaid
+%%{init: {'theme': 'dark'}}%%
 flowchart LR
    a --> b & c--> d
 ```
@@ -102,7 +103,7 @@ flowchart LR
 {line-numbers="1-2|3|4"}
 
 ```js
-    let a = 1;
+let a = 1;
 let b = 2;
 let c = x => 1 + 2 + x;
 c(3);

rendering/html.go

@@ -0,0 +1,90 @@
+package rendering
+
+import (
+	"bytes"
+	"fmt"
+	"html/template"
+	"regexp"
+
+	"github.com/gomarkdown/markdown/parser"
+
+	"github.com/baez90/goveal/config"
+)
+
+const (
+	parserExtensions = parser.NoIntraEmphasis | parser.Tables | parser.FencedCode |
+		parser.Autolink | parser.Strikethrough | parser.SpaceHeadings | parser.HeadingIDs |
+		parser.BackslashLineBreak | parser.DefinitionLists | parser.MathJax | parser.Titleblock |
+		parser.OrderedListStart | parser.Attributes
+)
+
+func ToHTML(markdown string, renderCfg config.Rendering) (rendered []byte, err error) {
+	var slides []rawSlide
+	if slides, err = splitIntoRawSlides(markdown, renderCfg); err != nil {
+		return nil, err
+	}
+
+	buf := templateRenderBufferPool.Get().(*bytes.Buffer)
+	defer func() {
+		buf.Reset()
+		templateRenderBufferPool.Put(buf)
+	}()
+
+	for idx := range slides {
+		if rendered, err := slides[idx].ToHTML(); err != nil {
+			return nil, err
+		} else {
+			buf.WriteString(string(rendered))
+		}
+	}
+
+	return buf.Bytes(), nil
+}
+
+type rawSlide struct {
+	Content  string
+	Children []rawSlide
+}
+
+func (s rawSlide) HasNotes() bool {
+	return notesLineRegexp.MatchString(s.Content)
+}
+
+func (s rawSlide) ToHTML() (template.HTML, error) {
+	if rendered, err := renderTemplate("slide.gohtml", s); err != nil {
+		return "", err
+	} else {
+		//nolint:gosec // should not be sanitized
+		return template.HTML(rendered), nil
+	}
+}
+
+func splitIntoRawSlides(markdown string, renderCfg config.Rendering) ([]rawSlide, error) {
+	var (
+		verticalSplit, horizontalSplit *regexp.Regexp
+		err                            error
+	)
+	if verticalSplit, err = regexp.Compile(fmt.Sprintf(splitFormat, renderCfg.VerticalSeparator)); err != nil {
+		return nil, err
+	}
+
+	if horizontalSplit, err = regexp.Compile(fmt.Sprintf(splitFormat, renderCfg.HorizontalSeparator)); err != nil {
+		return nil, err
+	}
+
+	horizontalSlides := horizontalSplit.Split(markdown, -1)
+	slides := make([]rawSlide, 0, len(horizontalSlides))
+	for _, hs := range horizontalSlides {
+		s := rawSlide{
+			Content: hs,
+		}
+		verticalSlides := verticalSplit.Split(hs, -1)
+		s.Children = make([]rawSlide, 0, len(verticalSlides))
+		for _, vs := range verticalSlides {
+			s.Children = append(s.Children, rawSlide{Content: vs})
+		}
+		slides = append(slides, s)
+	}
+
+	return slides, nil
+}

rendering/patterns.go

@@ -0,0 +1,19 @@
+package rendering
+
+import (
+	"fmt"
+	"regexp"
+)
+
+const (
+	// language=regexp
+	notesRegex = `(?i)notes?:`
+	// language=regexp
+	splitFormat = `\r?\n%s\r?\n`
+)
+
+var (
+	htmlElementAttributesRegexp = regexp.MustCompile(`(?P<key>[a-z]+(-[a-z]+)*)="(?P<value>.+)"`)
+	notesRegexp                 = regexp.MustCompile(fmt.Sprintf(`^%s`, notesRegex))
+	notesLineRegexp             = regexp.MustCompile(fmt.Sprintf(`\r?\n%s\r?\n`, notesRegex))
+)

rendering/render_to_reveal.go

@@ -2,65 +2,26 @@ package rendering
 
 import (
 	"bytes"
-	"embed"
 	"encoding/hex"
 	"hash"
 	"html"
 	"html/template"
 	"io"
 	"path"
-	"regexp"
-	"sync"
 
-	"github.com/Masterminds/sprig/v3"
 	"github.com/gomarkdown/markdown/ast"
 )
 
-var (
-	//go:embed templates/*.gohtml
-	templatesFS              embed.FS
-	templates                *template.Template
-	templateRenderBufferPool = &sync.Pool{
-		New: func() interface{} {
-			return new(bytes.Buffer)
-		},
-	}
-	htmlElementAttributesRegexp = regexp.MustCompile(`(?P<key>[a-z]+(-[a-z]+)*)="(?P<value>.+)"`)
-	notesRegexp                 = regexp.MustCompile(`^(?i)notes?`)
-)
-
 const (
 	mermaidCodeBlock = "mermaid"
 )
 
-func init() {
-	var err error
-	templates = template.New("rendering").Funcs(sprig.FuncMap())
-	if templates, err = templates.ParseFS(templatesFS, "templates/*.gohtml"); err != nil {
-		panic(err)
-	}
-}
-
 type RevealRenderer struct {
-	StateMachine *StateMachine
-	Hash         hash.Hash
-	hasNotes     bool
+	Hash hash.Hash
 }
 
-//nolint:gocyclo // under construction
 func (r *RevealRenderer) RenderHook(w io.Writer, node ast.Node, entering bool) (ast.WalkStatus, bool) {
 	switch b := node.(type) {
-	case *ast.Document:
-		if entering {
-			_, _ = w.Write([]byte("<section>\n"))
-			if next := peekNextRuler(b); next != nil && string(next.Literal) == "***" {
-				_, _ = w.Write([]byte("<section>\n"))
-				r.StateMachine.CurrentState = StateTypeNested
-			}
-		} else {
-			_, _ = w.Write([]byte("</section>\n"))
-		}
-		return ast.GoToNext, false
 	case *ast.ListItem:
 		if entering {
 			return r.handleListItem(w, b)
@@ -72,7 +33,6 @@ func (r *RevealRenderer) RenderHook(w io.Writer, node ast.Node, entering bool) (
 		}
 		if notesRegexp.Match(b.Literal) {
 			_, err := w.Write([]byte(`<aside class="notes">`))
-			r.hasNotes = true
 			return ast.SkipChildren, err == nil
 		}
 		return ast.GoToNext, false
@@ -81,18 +41,6 @@ func (r *RevealRenderer) RenderHook(w io.Writer, node ast.Node, entering bool) (
 			return r.handleCodeBlock(w, b)
 		}
 		return ast.GoToNext, false
-	case *ast.HorizontalRule:
-		next := peekNextRuler(b)
-		input := string(b.Literal)
-		if next != nil {
-			input += string(next.Literal)
-		}
-		if r.hasNotes {
-			_, _ = w.Write([]byte(`</aside>`))
-			r.hasNotes = false
-		}
-		_, _ = w.Write(r.StateMachine.Accept(input))
-		return ast.GoToNext, true
 	case *ast.Image:
 		if entering {
 			return r.handleImage(w, b)
@@ -215,17 +163,6 @@ func renderCodeTemplate(templateName string, codeBlock *ast.CodeBlock) (output [
 	return renderTemplate(templateName, data)
 }
 
-func renderTemplate(templateName string, data interface{}) (output []byte, err error) {
-	buffer := templateRenderBufferPool.Get().(*bytes.Buffer)
-	defer func() {
-		buffer.Reset()
-		templateRenderBufferPool.Put(buffer)
-	}()
-
-	err = templates.ExecuteTemplate(buffer, templateName, data)
-	return buffer.Bytes(), err
-}
-
 func lineNumbers(attrs *ast.Attribute) string {
 	if attrs == nil || attrs.Attrs == nil {
 		return ""

rendering/state.go

@@ -1,124 +0,0 @@
-package rendering
-
-import (
-	"fmt"
-
-	"github.com/gomarkdown/markdown/ast"
-)
-
-const (
-	EventTypeHorizontalSplit EventType = iota
-	EventTypeVerticalSplit
-	EventTypeHorizontalEnd
-	EventTypeVerticalSplitEnd
-	EventTypeVerticalDocumentEnd
-	EventTypeVerticalVerticalSplit
-
-	StateTypeRegular StateType = iota
-	StateTypeNested
-)
-
-var EventMapping = map[EventType][]byte{
-	EventTypeHorizontalSplit: []byte(`
-</section>
-<section>`),
-	EventTypeVerticalSplit: []byte(`
-</section>
-<section>
-<section>
-`),
-	EventTypeHorizontalEnd: []byte(`
-</section>
-`),
-	EventTypeVerticalSplitEnd: []byte(`
-</section>
-</section>
-<section>`),
-	EventTypeVerticalDocumentEnd: []byte(`
-</section>
-</section>
-`),
-	EventTypeVerticalVerticalSplit: []byte(`
-</section>
-</section>
-<section>
-<section>`),
-}
-
-func NewStateMachine(verticalSplit, horizontalSplit string) *StateMachine {
-	return &StateMachine{
-		CurrentState: StateTypeRegular,
-		States: map[StateType]State{
-			StateTypeRegular: {
-				Transitions: map[string]TransitionResult{
-					horizontalSplit: {EventTypeHorizontalSplit, StateTypeRegular},
-					fmt.Sprintf("%s%s", horizontalSplit, horizontalSplit): {EventTypeHorizontalSplit, StateTypeRegular},
-					fmt.Sprintf("%s%s", horizontalSplit, verticalSplit):   {EventTypeVerticalSplit, StateTypeNested},
-					fmt.Sprintf("%s%s", verticalSplit, horizontalSplit):   {EventTypeVerticalSplit, StateTypeNested},
-					"": {EventTypeHorizontalEnd, StateTypeRegular},
-				},
-			},
-			StateTypeNested: {
-				Transitions: map[string]TransitionResult{
-					fmt.Sprintf("%s%s", verticalSplit, verticalSplit): {EventTypeHorizontalSplit, StateTypeNested},
-					verticalSplit: {EventTypeHorizontalSplit, StateTypeNested},
-					fmt.Sprintf("%s%s", verticalSplit, horizontalSplit): {EventTypeVerticalSplitEnd, StateTypeNested},
-					horizontalSplit: {EventTypeVerticalSplitEnd, StateTypeRegular},
-					fmt.Sprintf("%s%s", horizontalSplit, verticalSplit):   {EventTypeVerticalVerticalSplit, StateTypeNested},
-					fmt.Sprintf("%s%s", horizontalSplit, horizontalSplit): {EventTypeVerticalSplitEnd, StateTypeRegular},
-					"": {EventTypeVerticalDocumentEnd, StateTypeRegular},
-				},
-			},
-		},
-	}
-}
-
-type (
-	EventType        uint
-	StateType        uint
-	TransitionResult struct {
-		EventType EventType
-		StateType StateType
-	}
-	State struct {
-		Transitions map[string]TransitionResult
-	}
-	StateMachine struct {
-		CurrentState StateType
-		States       map[StateType]State
-	}
-)
-
-func (m *StateMachine) Accept(input string) []byte {
-	if result, ok := m.States[m.CurrentState].Transitions[input]; ok {
-		m.CurrentState = result.StateType
-		return EventMapping[result.EventType]
-	}
-	return nil
-}
-
-func peekNextRuler(node ast.Node) *ast.HorizontalRule {
-	if node.AsContainer() == nil {
-		node = node.GetParent()
-	}
-
-	nodes := node.GetChildren()
-	if nodes == nil {
-		return nil
-	}
-
-	var selfIdx int
-	for idx := range nodes {
-		if nodes[idx] == node {
-			selfIdx = idx
-			break
-		}
-	}
-
-	for idx := selfIdx + 1; idx < len(nodes); idx++ {
-		if hr, ok := nodes[idx].(*ast.HorizontalRule); ok {
-			return hr
-		}
-	}
-	return nil
-}

rendering/templates.go

@@ -0,0 +1,61 @@
+package rendering
+
+import (
+	"bytes"
+	"embed"
+	"hash/fnv"
+	"html/template"
+	"sync"
+
+	"github.com/Masterminds/sprig/v3"
+	"github.com/gomarkdown/markdown"
+	mdhtml "github.com/gomarkdown/markdown/html"
+	"github.com/gomarkdown/markdown/parser"
+)
+
+var (
+	//go:embed templates/*.gohtml
+	templatesFS              embed.FS
+	templates                *template.Template
+	templateRenderBufferPool = &sync.Pool{
+		New: func() interface{} {
+			return new(bytes.Buffer)
+		},
+	}
+)
+
+func init() {
+	templates = template.New("rendering").
+		Funcs(sprig.FuncMap()).
+		Funcs(template.FuncMap{
+			"renderMarkdown": func(md string) template.HTML {
+				rr := &RevealRenderer{
+					Hash: fnv.New32a(),
+				}
+				mdParser := parser.NewWithExtensions(parserExtensions)
+				renderer := mdhtml.NewRenderer(mdhtml.RendererOptions{
+					Flags:          mdhtml.CommonFlags | mdhtml.HrefTargetBlank,
+					RenderNodeHook: rr.RenderHook,
+				})
+
+				renderedHTML := markdown.ToHTML([]byte(md), mdParser, renderer)
+				//nolint:gosec // template should be esacped
+				return template.HTML(renderedHTML)
+			},
+		})
+	var err error
+	if templates, err = templates.ParseFS(templatesFS, "templates/*.gohtml"); err != nil {
+		panic(err)
+	}
+}
+
+func renderTemplate(templateName string, data interface{}) (output []byte, err error) {
+	buffer := templateRenderBufferPool.Get().(*bytes.Buffer)
+	defer func() {
+		buffer.Reset()
+		templateRenderBufferPool.Put(buffer)
+	}()
+
+	err = templates.ExecuteTemplate(buffer, templateName, data)
+	return buffer.Bytes(), err
+}

rendering/templates/slide.gohtml

@@ -0,0 +1,12 @@
+<section>
+    {{ if .Children }}
+        {{ range .Children }}
+            {{ .ToHTML }}
+        {{ end }}
+    {{ else }}
+        {{ renderMarkdown .Content }}
+    {{ end }}
+    {{ if .HasNotes }}
+        </aside>
+    {{ end }}
+</section>

web/js/app.js

@@ -5,7 +5,6 @@ document.addEventListener("DOMContentLoaded", _ => {
         })
         .then(() => {
             subscribeToEvents()
-            console.info("finished initializing")
         })
 
 });
@@ -34,6 +33,7 @@ async function initReveal() {
     let cfg = await getRevealConfig()
     Reveal.initialize({
         controls: cfg.controls,
+        controlsLayout: cfg.controlsLayout,
         progress: cfg.progress,
         history: cfg.history,
         center: cfg.center,
@@ -44,6 +44,10 @@ async function initReveal() {
         menu: {
             numbers: cfg.menu.numbers,
             useTextContentForMissingTitles: cfg.menu.useTextContentForMissingTitles,
+            transitions: cfg.menu.transitions,
+            hideMissingTitles: cfg.hideMissingTitles,
+            markers: cfg.menu.markers,
+            openButton: cfg.menu.openButton,
             custom: [
                 {
                     title: 'Print',
@@ -64,7 +68,6 @@ async function initReveal() {
                 {name: 'Solarized', theme: '/reveal/dist/theme/solarized.css'},
                 {name: 'White', theme: '/reveal/dist/theme/white.css'}
             ],
-            transitions: true,
         },
         plugins: [RevealHighlight, RevealNotes, RevealMenu]
     })
@@ -87,20 +90,19 @@ function subscribeToEvents() {
     let source = new EventSource("/api/v1/events");
 
     source.onopen = (() => {
-        console.log("eventsource connection open");
+        console.debug("eventsource connection open");
     })
 
     source.onerror = (ev => {
         if (ev.target.readyState === 0) {
-            console.log("reconnecting to eventsource");
+            console.debug("reconnecting to eventsource");
         } else {
-            console.log("eventsource error", ev);
+            console.error("eventsource error", ev);
         }
     })
 
     source.onmessage = (ev => {
         let obj = JSON.parse(ev.data);
-        console.log(obj);
         switch (true) {
             case obj.forceReload:
                 window.location.reload()