wysiwyg: add minimal editor based on MarkdownEdit library

app/src/main/java/com/keylesspalace/tusky/components/compose/ComposeActivity.kt

@@ -524,6 +524,8 @@ class ComposeActivity : BaseActivity(),
         
         @ColorInt val color = ThemeUtils.getColor(this, if(enable) R.attr.colorPrimary else android.R.attr.textColorTertiary);
         composeFormattingSyntax.drawable.colorFilter = PorterDuffColorFilter(color, PorterDuff.Mode.SRC_IN);
+        
+        enableMarkdownWYSIWYGButtons(enable);
     }
     
     private fun setIconForSyntax(syntax: String, enable: Boolean) {
@@ -644,23 +646,43 @@ class ComposeActivity : BaseActivity(),
     }
     
     private fun codeButtonClicked() {
-        MarkdownEdit.addCode(composeEditField);
+        when(viewModel.formattingSyntax) {
+            "text/markdown" -> MarkdownEdit.addCode(composeEditField)
+            "text/bbcode" -> BBCodeEdit.addCode(composeEditField)
+            "text/html" -> HTMLEdit.addCode(composeEditField)
+        }
     }
     
     private fun linkButtonClicked() {
-        MarkdownEdit.addLink(composeEditField);
+        when(viewModel.formattingSyntax) {
+            "text/markdown" -> MarkdownEdit.addLink(composeEditField)
+            "text/bbcode" -> BBCodeEdit.addLink(composeEditField)
+            "text/html" -> HTMLEdit.addLink(composeEditField)
+        }
     }
     
     private fun strikethroughButtonClicked() {
-        MarkdownEdit.addStrikeThrough(composeEditField);
+        when(viewModel.formattingSyntax) {
+            "text/markdown" -> MarkdownEdit.addStrikeThrough(composeEditField)
+            "text/bbcode" -> BBCodeEdit.addStrikeThrough(composeEditField)
+            "text/html" -> HTMLEdit.addStrikeThrough(composeEditField)
+        }
     }
     
     private fun italicButtonClicked() {
-        MarkdownEdit.addItalic(composeEditField);
+        when(viewModel.formattingSyntax) {
+            "text/markdown" -> MarkdownEdit.addItalic(composeEditField)
+            "text/bbcode" -> BBCodeEdit.addItalic(composeEditField)
+            "text/html" -> HTMLEdit.addItalic(composeEditField)
+        }
     }
     
     private fun boldButtonClicked() {
-        MarkdownEdit.addBold(composeEditField);
+        when(viewModel.formattingSyntax) {
+            "text/markdown" -> MarkdownEdit.addBold(composeEditField)
+            "text/bbcode" -> BBCodeEdit.addBold(composeEditField)
+            "text/html" -> HTMLEdit.addBold(composeEditField)
+        }
     }
 
     override fun onSaveInstanceState(outState: Bundle) {

app/src/main/java/com/keylesspalace/tusky/util/BBCodeEdit.java

@@ -0,0 +1,83 @@
+package com.keylesspalace.tusky.util;
+
+import androidx.annotation.IntDef;
+import androidx.annotation.IntRange;
+import androidx.annotation.NonNull;
+import androidx.annotation.VisibleForTesting;
+import android.text.Editable;
+import android.text.Selection;
+import android.text.Spannable;
+import android.widget.EditText;
+import me.thanel.markdownedit.SelectionUtils;
+
+public class BBCodeEdit {
+    private BBCodeEdit() { /* cannot be instantiated */ }
+
+    public static void addBold(@NonNull Editable text) {
+        HTMLEdit.surroundSelectionWith(text, "[b]", "[/b]");
+    }
+
+    public static void addBold(@NonNull EditText editText) {
+        addBold(editText.getText());
+    }
+
+    public static void addItalic(@NonNull Editable text) {
+        HTMLEdit.surroundSelectionWith(text, "[i]", "[/i]");
+    }
+
+    public static void addItalic(@NonNull EditText editText) {
+        addItalic(editText.getText());
+    }
+
+    public static void addStrikeThrough(@NonNull Editable text) {
+        HTMLEdit.surroundSelectionWith(text, "[s]", "[/s]");
+    }
+
+    public static void addStrikeThrough(@NonNull EditText editText) {
+        addStrikeThrough(editText.getText());
+    }
+
+    public static void addLink(@NonNull Editable text) {
+        if (!SelectionUtils.hasSelection(text)) {
+            SelectionUtils.selectWordAroundCursor(text);
+        }
+        String selectedText = SelectionUtils.getSelectedText(text).toString().trim();
+
+        int selectionStart = SelectionUtils.getSelectionStart(text);
+
+        String begin = "[url=url]";
+        String end = "[/url]";
+        String result = begin + selectedText + end;
+        SelectionUtils.replaceSelectedText(text, result);
+
+        if (selectedText.length() == 0) {
+            Selection.setSelection(text, selectionStart + begin.length());
+        } else {
+            selectionStart = selectionStart + 5; // [url=".length()
+            Selection.setSelection(text, selectionStart, selectionStart + 3);
+        }
+    }
+
+    public static void addLink(@NonNull EditText editText) {
+        addLink(editText.getText());
+    }
+    
+    /**
+     * Inserts a markdown code block to the specified EditText at the currently selected position.
+     *
+     * @param text The {@link Editable} view to which to add markdown code block.
+     */
+    public static void addCode(@NonNull Editable text) {
+        HTMLEdit.surroundSelectionWith(text, "[code]", "[/code]");
+    }
+
+    /**
+     * Inserts a markdown code block to the specified EditText at the currently selected position.
+     *
+     * @param editText The {@link EditText} view to which to add markdown code block.
+     */
+    public static void addCode(@NonNull EditText editText) {
+        addCode(editText.getText());
+    }
+}
+ 

app/src/main/java/com/keylesspalace/tusky/util/HTMLEdit.java

@@ -0,0 +1,104 @@
+package com.keylesspalace.tusky.util;
+
+import androidx.annotation.IntDef;
+import androidx.annotation.IntRange;
+import androidx.annotation.NonNull;
+import androidx.annotation.VisibleForTesting;
+import android.text.Editable;
+import android.text.Selection;
+import android.text.Spannable;
+import android.widget.EditText;
+import me.thanel.markdownedit.SelectionUtils;
+
+public class HTMLEdit {
+    private HTMLEdit() { /* cannot be instantiated */ }
+
+    public static void addBold(@NonNull Editable text) {
+        surroundSelectionWith(text, "<b>", "</b>");
+    }
+
+    public static void addBold(@NonNull EditText editText) {
+        addBold(editText.getText());
+    }
+
+    public static void addItalic(@NonNull Editable text) {
+        surroundSelectionWith(text, "<i>", "</i>");
+    }
+
+    public static void addItalic(@NonNull EditText editText) {
+        addItalic(editText.getText());
+    }
+
+    public static void addStrikeThrough(@NonNull Editable text) {
+        surroundSelectionWith(text, "<del>", "</del>");
+    }
+
+    public static void addStrikeThrough(@NonNull EditText editText) {
+        addStrikeThrough(editText.getText());
+    }
+
+    public static void addLink(@NonNull Editable text) {
+        if (!SelectionUtils.hasSelection(text)) {
+            SelectionUtils.selectWordAroundCursor(text);
+        }
+        String selectedText = SelectionUtils.getSelectedText(text).toString().trim();
+
+        int selectionStart = SelectionUtils.getSelectionStart(text);
+
+        String begin = "<a href=\"url\">";
+        String end = "</a>";
+        String result = begin + selectedText + end;
+        SelectionUtils.replaceSelectedText(text, result);
+
+        if (selectedText.length() == 0) {
+            Selection.setSelection(text, selectionStart + begin.length());
+        } else {
+            selectionStart = selectionStart + 9; // <a href=".length()
+            Selection.setSelection(text, selectionStart, selectionStart + 3);
+        }
+    }
+
+    public static void addLink(@NonNull EditText editText) {
+        addLink(editText.getText());
+    }
+    
+    /**
+     * Inserts a markdown code block to the specified EditText at the currently selected position.
+     *
+     * @param text The {@link Editable} view to which to add markdown code block.
+     */
+    public static void addCode(@NonNull Editable text) {
+        surroundSelectionWith(text, "<code>", "</code>");
+    }
+
+    /**
+     * Inserts a markdown code block to the specified EditText at the currently selected position.
+     *
+     * @param editText The {@link EditText} view to which to add markdown code block.
+     */
+    public static void addCode(@NonNull EditText editText) {
+        addCode(editText.getText());
+    }
+
+    public static void surroundSelectionWith(@NonNull Editable text, @NonNull String surroundText, @NonNull String surroundText2) {
+        if (!SelectionUtils.hasSelection(text)) {
+            SelectionUtils.selectWordAroundCursor(text);
+        }
+        CharSequence selectedText = SelectionUtils.getSelectedText(text);
+        int selectionStart = SelectionUtils.getSelectionStart(text);
+
+        selectedText = selectedText.toString().trim();
+
+        StringBuilder result = new StringBuilder();
+        result.append(surroundText).append(selectedText).append(surroundText2);
+        
+        int charactersToGoBack = 0;
+        if (selectedText.length() == 0) {
+            charactersToGoBack = surroundText2.length();
+        }
+
+        SelectionUtils.replaceSelectedText(text, result);
+        Selection.setSelection(text, selectionStart + result.length() - charactersToGoBack);
+    }
+
+}