package rendering.source;

import com.github.javaparser.Range;

import com.github.javaparser.ast.comments.BlockComment;

import com.github.javaparser.ast.comments.JavadocComment;

import com.github.javaparser.ast.comments.LineComment;

import com.github.javaparser.ast.expr.StringLiteralExpr;

import com.github.javaparser.ast.expr.TextBlockLiteralExpr;

import com.github.javaparser.ast.visitor.VoidVisitorAdapter;

import java.util.Optional;

/**

 * Applies syntax highlighting to the source by recording the changes that are need

 * in the rendering queue.

 */

public class ApplySyntaxHighlightingVisitor  extends VoidVisitorAdapter<Void> {

    private final RenderingQueue renderingQueue;

    public ApplySyntaxHighlightingVisitor(

            RenderingQueue renderingQueue

    ) {

        this.renderingQueue = renderingQueue;

    }

    private void highlightToken(

            Optional<Range> range,

            String cssClass

    ) {

        int startLineNum = range.get().begin.line;

        int startCol = range.get().begin.column;

        int endLineNum = range.get().end.line;

        int endCol = range.get().end.column;

        final String startTag = "<span class='" + cssClass+ "'>";

        final String endTag = "</span>";

        renderingQueue.add(

                startLineNum,

                startCol,

                new ContentRecord(

                        startTag,

                        PositionType.BEFORE

                )

        );

        renderingQueue.add(

                endLineNum,

                endCol,

                new ContentRecord(

                        endTag,

                        PositionType.AFTER

                )

        );

        if (startLineNum != endLineNum) {

            renderingQueue.endOfLine(startLineNum, endTag);

            for (int i = startLineNum + 1; i < endLineNum; i++) {

                renderingQueue.beginningOfLine(i, startTag);

                renderingQueue.endOfLine(i, endTag);

            }

            renderingQueue.endOfLine(endLineNum, endTag);

        }

    }

    @Override

    public void visit(LineComment comment, Void arg) {

        highlightToken(comment.getRange(), "comment");

        super.visit(comment, arg);

    }

    @Override

    public void visit(JavadocComment comment, Void arg) {

        highlightToken(comment.getRange(), "comment");

        super.visit(comment, arg);

    }

    @Override

    public void visit(BlockComment comment, Void arg) {

        highlightToken(comment.getRange(), "comment");

        super.visit(comment, arg);

    }

    @Override

    public void visit(StringLiteralExpr str, Void arg) {

        highlightToken(str.getRange(), "string");

        super.visit(str, arg);

    }

    @Override

    public void visit(TextBlockLiteralExpr str, Void arg) {

        highlightToken(str.getRange(), "string");

        super.visit(str, arg);

    }

}