Add codeblock

src/commands/markdown-commands/codeBlock.tsx

@@ -0,0 +1,57 @@
+import * as React from "react";
+import { Command } from "../command";
+import { textHelpers } from "../../helpers/textHelpers";
+
+export const codeBlock: Command = {
+  execute: async ({ textApi, initialState }) => {
+    // Adjust the selection to encompass the whole word if the caret is inside one
+    const newSelectionRange = textHelpers.selectWord({
+      text: initialState.text,
+      selection: initialState.selection
+    });
+    const state1 = textApi.setSelectionRange(newSelectionRange);
+
+    // when there's no breaking line
+    if (textHelpers.getSelectedText(state1).indexOf("\n") === -1) {
+      textApi.replaceSelection(`\`${textHelpers.getSelectedText(state1)}\``);
+      // Adjust the selection to not contain the **
+
+      const selectionStart = state1.selection.start + 1;
+      const selectionEnd =
+        selectionStart + textHelpers.getSelectedText(state1).length;
+
+      textApi.setSelectionRange({
+        start: selectionStart,
+        end: selectionEnd
+      });
+      return;
+    }
+
+    const breaksBeforeCount = textHelpers.getBreaksNeededForEmptyLineBefore(
+      state1.text,
+      state1.selection.start
+    );
+    const breaksBefore = Array(breaksBeforeCount + 1).join("\n");
+
+    const breaksAfterCount = textHelpers.getBreaksNeededForEmptyLineAfter(
+      state1.text,
+      state1.selection.end
+    );
+    const breaksAfter = Array(breaksAfterCount + 1).join("\n");
+
+    textApi.replaceSelection(
+      `${breaksBefore}\`\`\`\n${textHelpers.getSelectedText(
+        state1
+      )}\n\`\`\`${breaksAfter}`
+    );
+
+    const selectionStart = state1.selection.start + breaksBeforeCount + 4;
+    const selectionEnd =
+      selectionStart + textHelpers.getSelectedText(state1).length;
+
+    textApi.setSelectionRange({
+      start: selectionStart,
+      end: selectionEnd
+    });
+  }
+};