Add sample-latex-math module

sample-latex-math/build.gradle

@@ -0,0 +1,23 @@
+apply plugin: 'com.android.application'
+
+android {
+
+    compileSdkVersion config['compile-sdk']
+    buildToolsVersion config['build-tools']
+
+    defaultConfig {
+
+        applicationId "ru.noties.markwon.sample.jlatexmath"
+
+        minSdkVersion config['min-sdk']
+        targetSdkVersion config['target-sdk']
+        versionCode 1
+        versionName version
+    }
+}
+
+dependencies {
+    implementation project(':markwon')
+    implementation project(':markwon-image-loader')
+    implementation 'ru.noties:jlatexmath-android:0.1.0'
+}

sample-latex-math/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="ru.noties.markwon.sample.jlatexmath">
+
+    <application
+        android:allowBackup="true"
+        android:label="@string/app_name"
+        android:supportsRtl="true"
+        android:theme="@style/AppTheme">
+        <activity android:name=".MainActivity">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>

sample-latex-math/src/main/java/ru/noties/markwon/sample/jlatexmath/JLatexMathBlock.java

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+package ru.noties.markwon.sample.jlatexmath;
+
+import org.commonmark.node.CustomBlock;
+
+public class JLatexMathBlock extends CustomBlock {
+
+    private String latex;
+
+    public String latex() {
+        return latex;
+    }
+
+    public void latex(String latex) {
+        this.latex = latex;
+    }
+}

sample-latex-math/src/main/java/ru/noties/markwon/sample/jlatexmath/JLatexMathBlockParser.java

@@ -0,0 +1,79 @@
+package ru.noties.markwon.sample.jlatexmath;
+
+import org.commonmark.node.Block;
+import org.commonmark.parser.block.AbstractBlockParser;
+import org.commonmark.parser.block.AbstractBlockParserFactory;
+import org.commonmark.parser.block.BlockContinue;
+import org.commonmark.parser.block.BlockStart;
+import org.commonmark.parser.block.MatchedBlockParser;
+import org.commonmark.parser.block.ParserState;
+
+public class JLatexMathBlockParser extends AbstractBlockParser {
+
+    private final JLatexMathBlock block = new JLatexMathBlock();
+
+    private final StringBuilder builder = new StringBuilder();
+
+    private boolean isClosed;
+
+    @Override
+    public Block getBlock() {
+        return block;
+    }
+
+    @Override
+    public BlockContinue tryContinue(ParserState parserState) {
+
+        if (isClosed) {
+            return BlockContinue.finished();
+        }
+
+        return BlockContinue.atIndex(parserState.getIndex());
+    }
+
+    @Override
+    public void addLine(CharSequence line) {
+
+        if (builder.length() > 0) {
+            builder.append('\n');
+        }
+
+        builder.append(line);
+
+        final int length = builder.length();
+        if (length > 1) {
+            isClosed = '$' == builder.charAt(length - 1)
+                    && '$' == builder.charAt(length - 2);
+            if (isClosed) {
+                builder.replace(length - 2, length, "");
+            }
+        }
+    }
+
+    @Override
+    public void closeBlock() {
+        block.latex(builder.toString());
+    }
+
+    public static class Factory extends AbstractBlockParserFactory {
+
+        @Override
+        public BlockStart tryStart(ParserState state, MatchedBlockParser matchedBlockParser) {
+
+            final CharSequence line = state.getLine();
+            final int length = line != null
+                    ? line.length()
+                    : 0;
+
+            if (length > 1) {
+                if ('$' == line.charAt(0)
+                        && '$' == line.charAt(1)) {
+                    return BlockStart.of(new JLatexMathBlockParser())
+                            .atIndex(state.getIndex() + 2);
+                }
+            }
+
+            return BlockStart.none();
+        }
+    }
+}

sample-latex-math/src/main/java/ru/noties/markwon/sample/jlatexmath/JLatexMathMedia.java

@@ -0,0 +1,137 @@
+package ru.noties.markwon.sample.jlatexmath;
+
+import android.graphics.drawable.Drawable;
+import android.net.Uri;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.util.Log;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.io.UnsupportedEncodingException;
+import java.util.Scanner;
+
+import ru.noties.jlatexmath.JLatexMathDrawable;
+import ru.noties.markwon.il.ImageItem;
+import ru.noties.markwon.il.MediaDecoder;
+import ru.noties.markwon.il.SchemeHandler;
+
+public class JLatexMathMedia {
+
+    public static class Config {
+
+        protected final float textSize;
+
+        protected Drawable background;
+
+        @JLatexMathDrawable.Align
+        protected int align = JLatexMathDrawable.ALIGN_CENTER;
+
+        protected boolean fitCanvas = true;
+
+        protected int padding;
+
+        public Config(float textSize) {
+            this.textSize = textSize;
+        }
+    }
+
+    public static final String SCHEME = "jlatexmath";
+
+    @NonNull
+    public static String makeDestination(@NonNull String latex) {
+        return SCHEME + "://" + latex;
+    }
+
+    private static final String CONTENT_TYPE = "text/jlatexmath";
+
+    private final Config config;
+
+    public JLatexMathMedia(@NonNull Config config) {
+        this.config = config;
+    }
+
+    @NonNull
+    public SchemeHandler schemeHandler() {
+        return new SchemeHandlerImpl();
+    }
+
+    @NonNull
+    public MediaDecoder mediaDecoder() {
+        return new MediaDecoderImpl(config);
+    }
+
+    static class SchemeHandlerImpl extends SchemeHandler {
+
+        @Nullable
+        @Override
+        public ImageItem handle(@NonNull String raw, @NonNull Uri uri) {
+
+            Log.e("handle", raw);
+
+            ImageItem item = null;
+
+            try {
+                final byte[] bytes = raw.substring(SCHEME.length()).getBytes("UTF-8");
+                item = new ImageItem(
+                        CONTENT_TYPE,
+                        new ByteArrayInputStream(bytes),
+                        null
+                );
+            } catch (UnsupportedEncodingException e) {
+                e.printStackTrace();
+            }
+
+            return item;
+        }
+
+        @Override
+        public void cancel(@NonNull String raw) {
+            // no op
+        }
+    }
+
+    static class MediaDecoderImpl extends MediaDecoder {
+
+        private final Config config;
+
+        MediaDecoderImpl(@NonNull Config config) {
+            this.config = config;
+        }
+
+        @Override
+        public boolean canDecodeByContentType(@Nullable String contentType) {
+            return CONTENT_TYPE.equals(contentType);
+        }
+
+        @Override
+        public boolean canDecodeByFileName(@NonNull String fileName) {
+            return false;
+        }
+
+        @Nullable
+        @Override
+        public Drawable decode(@NonNull InputStream inputStream) {
+
+            final Scanner scanner = new Scanner(inputStream, "UTF-8").useDelimiter("\\A");
+            final String latex = scanner.hasNext()
+                    ? scanner.next()
+                    : null;
+
+            Log.e("decode", latex);
+
+            if (latex == null) {
+                return null;
+            }
+
+            // todo: change to float
+            return JLatexMathDrawable.builder(latex)
+                    .textSize((int) config.textSize)
+                    .background(config.background)
+                    .align(config.align)
+                    .fitCanvas(config.fitCanvas)
+                    .padding(config.padding)
+                    .build();
+        }
+    }
+}

sample-latex-math/src/main/java/ru/noties/markwon/sample/jlatexmath/MainActivity.java

@@ -0,0 +1,113 @@
+package ru.noties.markwon.sample.jlatexmath;
+
+import android.app.Activity;
+import android.os.Bundle;
+import android.util.Log;
+import android.widget.TextView;
+
+import org.commonmark.node.CustomBlock;
+import org.commonmark.node.Node;
+import org.commonmark.parser.Parser;
+
+import ru.noties.jlatexmath.JLatexMathAndroid;
+import ru.noties.jlatexmath.JLatexMathDrawable;
+import ru.noties.markwon.Markwon;
+import ru.noties.markwon.SpannableBuilder;
+import ru.noties.markwon.SpannableConfiguration;
+import ru.noties.markwon.il.AsyncDrawableLoader;
+import ru.noties.markwon.renderer.ImageSize;
+import ru.noties.markwon.renderer.SpannableMarkdownVisitor;
+
+public class MainActivity extends Activity {
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+
+        // todo: later version has automatic initialization
+        JLatexMathAndroid.init(this);
+
+        final TextView textView = findViewById(R.id.text_view);
+
+        // this one fails due input sanitizing on commonmark-java side
+        String latex = "\\begin{array}{l}";
+        latex += "\\forall\\varepsilon\\in\\mathbb{R}_+^*\\ \\exists\\eta>0\\ |x-x_0|\\leq\\eta\\Longrightarrow|f(x)-f(x_0)|\\leq\\varepsilon\\\\";
+        latex += "\\det\\begin{bmatrix}a_{11}&a_{12}&\\cdots&a_{1n}\\\\a_{21}&\\ddots&&\\vdots\\\\\\vdots&&\\ddots&\\vdots\\\\a_{n1}&\\cdots&\\cdots&a_{nn}\\end{bmatrix}\\overset{\\mathrm{def}}{=}\\sum_{\\sigma\\in\\mathfrak{S}_n}\\varepsilon(\\sigma)\\prod_{k=1}^n a_{k\\sigma(k)}\\\\";
+        latex += "\\sideset{_\\alpha^\\beta}{_\\gamma^\\delta}{\\begin{pmatrix}a&b\\\\c&d\\end{pmatrix}}\\\\";
+        latex += "\\int_0^\\infty{x^{2n} e^{-a x^2}\\,dx} = \\frac{2n-1}{2a} \\int_0^\\infty{x^{2(n-1)} e^{-a x^2}\\,dx} = \\frac{(2n-1)!!}{2^{n+1}} \\sqrt{\\frac{\\pi}{a^{2n+1}}}\\\\";
+        latex += "\\int_a^b{f(x)\\,dx} = (b - a) \\sum\\limits_{n = 1}^\\infty  {\\sum\\limits_{m = 1}^{2^n  - 1} {\\left( { - 1} \\right)^{m + 1} } } 2^{ - n} f(a + m\\left( {b - a} \\right)2^{-n} )\\\\";
+        latex += "\\int_{-\\pi}^{\\pi} \\sin(\\alpha x) \\sin^n(\\beta x) dx = \\textstyle{\\left \\{ \\begin{array}{cc} (-1)^{(n+1)/2} (-1)^m \\frac{2 \\pi}{2^n} \\binom{n}{m} & n \\mbox{ odd},\\ \\alpha = \\beta (2m-n) \\\\ 0 & \\mbox{otherwise} \\\\ \\end{array} \\right .}\\\\";
+        latex += "L = \\int_a^b \\sqrt{ \\left|\\sum_{i,j=1}^ng_{ij}(\\gamma(t))\\left(\\frac{d}{dt}x^i\\circ\\gamma(t)\\right)\\left(\\frac{d}{dt}x^j\\circ\\gamma(t)\\right)\\right|}\\,dt\\\\";
+        latex += "\\begin{array}{rl} s &= \\int_a^b\\left\\|\\frac{d}{dt}\\vec{r}\\,(u(t),v(t))\\right\\|\\,dt \\\\ &= \\int_a^b \\sqrt{u'(t)^2\\,\\vec{r}_u\\cdot\\vec{r}_u + 2u'(t)v'(t)\\, \\vec{r}_u\\cdot\\vec{r}_v+ v'(t)^2\\,\\vec{r}_v\\cdot\\vec{r}_v}\\,\\,\\, dt. \\end{array}\\\\";
+        latex += "\\end{array}";
+
+//        String latex = "\\text{A long division \\longdiv{12345}{13}";
+//                String latex = "{a \\bangle b} {c \\brace d} {e \\brack f} {g \\choose h}";
+
+//        String latex = "\\begin{array}{cc}";
+//        latex += "\\fbox{\\text{A framed box with \\textdbend}}&\\shadowbox{\\text{A shadowed box}}\\cr";
+//        latex += "\\doublebox{\\text{A double framed box}}&\\ovalbox{\\text{An oval framed box}}\\cr";
+//        latex += "\\end{array}";
+
+        // mention another way of doing this: through async drawable to process formulas in background
+
+
+        final JLatexMathMedia.Config config = new JLatexMathMedia.Config(textView.getTextSize()) {{
+//            align = JLatexMathDrawable.ALIGN_RIGHT;
+        }};
+        final JLatexMathMedia jLatexMathMedia = new JLatexMathMedia(config);
+
+        final AsyncDrawableLoader asyncDrawableLoader = AsyncDrawableLoader.builder()
+                .schemeHandler(JLatexMathMedia.SCHEME, jLatexMathMedia.schemeHandler())
+                .mediaDecoders(jLatexMathMedia.mediaDecoder())
+                .build();
+
+        final SpannableConfiguration configuration = SpannableConfiguration.builder(this)
+                .asyncDrawableLoader(asyncDrawableLoader)
+                .build();
+
+        final String markdown = "# Example of LaTeX\n\n$$"
+                + latex + "$$\n\n something like **this**";
+
+        final Parser parser = new Parser.Builder()
+                .customBlockParserFactory(new JLatexMathBlockParser.Factory())
+                .build();
+
+        final Node node = parser.parse(markdown);
+        final SpannableBuilder builder = new SpannableBuilder();
+        final SpannableMarkdownVisitor visitor = new SpannableMarkdownVisitor(SpannableConfiguration.create(this), builder) {
+
+            @Override
+            public void visit(CustomBlock customBlock) {
+
+                if (!(customBlock instanceof JLatexMathBlock)) {
+                    super.visit(customBlock);
+                    return;
+                }
+
+                final String latex = ((JLatexMathBlock) customBlock).latex();
+
+                final int length = builder.length();
+                builder.append(latex);
+
+                SpannableBuilder.setSpans(
+                        builder,
+                        configuration.factory().image(
+                                configuration.theme(),
+                                JLatexMathMedia.makeDestination(latex),
+                                configuration.asyncDrawableLoader(),
+                                configuration.imageSizeResolver(),
+                                new ImageSize(new ImageSize.Dimension(100, "%"), null),
+                                false
+                        ),
+                        length,
+                        builder.length()
+                );
+            }
+        };
+        node.accept(visitor);
+
+        Markwon.setText(textView, builder.text());
+    }
+}

sample-latex-math/src/main/res/layout/activity_main.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:clipChildren="false"
+    android:clipToPadding="false">
+
+    <TextView
+        android:id="@+id/text_view"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:padding="16dip" />
+
+</ScrollView>

sample-latex-math/src/main/res/values/strings.xml

@@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">Markwon-JLatexMath</string>
+</resources>

sample-latex-math/src/main/res/values/styles.xml

@@ -0,0 +1,6 @@
+<resources>
+
+    <style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar">
+    </style>
+
+</resources>

settings.gradle

@@ -1,3 +1,3 @@
 rootProject.name = 'MarkwonProject'
-include ':app', ':markwon', ':markwon-image-loader', ':markwon-view', ':sample-custom-extension',
+include ':app', ':markwon', ':markwon-image-loader', ':markwon-view', ':sample-custom-extension', ':sample-latex-math',
         ':markwon-syntax-highlight', ':markwon-html-parser-api', ':markwon-html-parser-impl'