diff --git a/src/components/SourceViewer/SourceViewer.tsx b/src/components/SourceViewer/SourceViewer.tsx
index a05d11a..5be1d70 100644
--- a/src/components/SourceViewer/SourceViewer.tsx
+++ b/src/components/SourceViewer/SourceViewer.tsx
@@ -1,7 +1,147 @@
 import React from "react";
 import Highlight, { defaultProps } from "prism-react-renderer";
 
+import {
+  TgetLineProps,
+  TgetTokenProps,
+  StyleObj,
+  Token,
+} from "../../types/prism-types";
+
 import { sourceMapping } from "../../logic/sourceMapping";
+import {
+  completionMapping,
+  ICompletionDetail,
+} from "../../logic/completionMapping";
+
+function getCompletionFromSourceToken(
+  matcheeToken: Token
+): ICompletionDetail | null {
+  const matchingSourceDetails = sourceMapping.mappingArray.find(
+    ({ token: tmpToken }) => matcheeToken === tmpToken
+  );
+  if (matchingSourceDetails === undefined) {
+    return null;
+  }
+
+  const { start: sourceStart, end: sourceEnd } = matchingSourceDetails;
+
+  let closestCompletion: ICompletionDetail | null = null;
+  let closestMatchScore = -Infinity;
+
+  completionMapping.completionDetails.forEach((tmpCompletionDetails) => {
+    const { start: compStart, end: compEnd } = tmpCompletionDetails;
+    const sourceLen = sourceEnd - sourceStart;
+    const compLen = compEnd - compStart;
+
+    // If not intersecting at all, ignore
+    if (compEnd < sourceStart || compStart > sourceEnd) {
+      return;
+    }
+
+    const intersectionStart = Math.max(sourceStart, compStart);
+    const intersectionEnd = Math.min(sourceEnd, compEnd);
+
+    const intersectionDistance = intersectionEnd - intersectionStart;
+    // Exclusion =  Total Len - (2 * intersection)
+    const exclusionDistance = sourceLen + compLen - intersectionDistance;
+
+    const score = intersectionDistance - exclusionDistance;
+    if (score >= closestMatchScore) {
+      closestCompletion = tmpCompletionDetails;
+      closestMatchScore = score;
+    }
+  });
+
+  return closestCompletion;
+}
+
+interface IPreRendererProps {
+  className: string;
+  style: StyleObj;
+  tokens: Token[][];
+  getLineProps: TgetLineProps;
+  getTokenProps: TgetTokenProps;
+}
+function PreRenderer({
+  className,
+  style,
+  tokens,
+  getLineProps,
+  getTokenProps,
+}: IPreRendererProps) {
+  sourceMapping.reset();
+  return (
+    <pre className={`${className} px-4 py-2 overflow-auto`} style={style}>
+      {tokens.map((line, i) => (
+        <LineRenderer
+          key={i}
+          line={line}
+          getLineProps={getLineProps}
+          getTokenProps={getTokenProps}
+        />
+      ))}
+    </pre>
+  );
+}
+
+interface ILineRendererProps {
+  line: Token[];
+  getLineProps: TgetLineProps;
+  getTokenProps: TgetTokenProps;
+}
+function LineRenderer({
+  line,
+  getLineProps,
+  getTokenProps,
+}: ILineRendererProps) {
+  return (
+    <div {...getLineProps({ line })}>
+      {/* Refactor into TokenRenderer */}
+      {line.map((token, i) => (
+        <TokenRenderer
+          key={i}
+          token={token}
+          isLastTokenInLine={i === line.length - 1}
+          getTokenProps={getTokenProps}
+        />
+      ))}
+    </div>
+  );
+}
+
+interface ITokenRendererProps {
+  token: Token;
+  isLastTokenInLine: boolean;
+  getTokenProps: TgetTokenProps;
+}
+function TokenRenderer({
+  token,
+  isLastTokenInLine,
+  getTokenProps,
+}: ITokenRendererProps) {
+  const refFn = sourceMapping.registerToken(token);
+  if (isLastTokenInLine) {
+    sourceMapping.registerLineEnd();
+  }
+
+  const onClickToken = (tmpToken: Token) => {
+    const matchingCompletion = getCompletionFromSourceToken(tmpToken);
+    if (matchingCompletion !== null) {
+      console.log(
+        `Clicked: ${tmpToken.content} => Completion (${matchingCompletion.completionType},${matchingCompletion.completionValueString})`
+      );
+    }
+  };
+
+  return (
+    <span
+      ref={refFn}
+      {...getTokenProps({ token })}
+      onClick={() => onClickToken(token)}
+    />
+  );
+}
 
 interface ISourceViewerProps {
   code: string;
@@ -10,6 +150,7 @@ interface ISourceViewerProps {
 
 export function SourceViewer(props: ISourceViewerProps) {
   const { code } = props;
+
   return (
     <div>
       {/* Title of code section */}
@@ -17,26 +158,9 @@ export function SourceViewer(props: ISourceViewerProps) {
       {/* Code viewer */}
       <Highlight {...defaultProps} code={code} language="jsx">
         {({ className, style, tokens, getLineProps, getTokenProps }) => (
-          // eslint-disable-next-line no-sequences
-          sourceMapping.reset(),
-          (
-            <pre
-              className={`${className} px-4 py-2 overflow-auto`}
-              style={style}
-            >
-              {tokens.map((line, i) => (
-                <div {...getLineProps({ line, key: i })}>
-                  {line.map(function (token, key) {
-                    const refFn = sourceMapping.registerToken(token);
-                    return (
-                      <span ref={refFn} {...getTokenProps({ token, key })} />
-                    );
-                  })}
-                  {(sourceMapping.registerLineEnd(), null)}
-                </div>
-              ))}
-            </pre>
-          )
+          <PreRenderer
+            {...{ className, style, tokens, getLineProps, getTokenProps }}
+          />
         )}
       </Highlight>
     </div>