package org.simantics.scl.ui.editor.completion;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.DefaultInformationControl;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IInformationControl;
import org.eclipse.jface.text.IInformationControlCreator;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.contentassist.ICompletionProposal;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension2;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension3;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension4;
import org.eclipse.jface.text.contentassist.ICompletionProposalExtension5;
import org.eclipse.jface.text.contentassist.IContextInformation;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Shell;
import org.simantics.scl.compiler.elaboration.modules.SCLValue;
import org.simantics.scl.ui.Activator;

public class SCLCompletionProposal implements ICompletionProposal, ICompletionProposalExtension, ICompletionProposalExtension2, ICompletionProposalExtension3, ICompletionProposalExtension4, ICompletionProposalExtension5 {
    
    private static final Image PRIVATE = Activator.imageDescriptorFromPlugin("org.simantics.scl.ui", "icons/private_co.gif").createImage(); //$NON-NLS-1$ //$NON-NLS-2$
    private static final Image PUBLIC = Activator.imageDescriptorFromPlugin("org.simantics.scl.ui", "icons/public_co.gif").createImage(); //$NON-NLS-1$ //$NON-NLS-2$
    private static final Image CONST = Activator.imageDescriptorFromPlugin("org.simantics.scl.ui", "icons/container_obj.gif").createImage(); //$NON-NLS-1$ //$NON-NLS-2$
    private static final Image TYPE = Activator.imageDescriptorFromPlugin("org.simantics.scl.ui", "icons/typedef_obj.gif").createImage(); //$NON-NLS-1$ //$NON-NLS-2$
    
    private final String content;
    private final String name;
    private final String module;
    private final String documentation;
    private int replacementOffset;
    private String prefix;
    private final SCLCompletionType completionType;
    
    public SCLCompletionProposal(SCLValue value, int replacementOffset, String prefix) {
        String tempName = value.getName().name;
        String tempModule = value.getName().module;
        int p = tempName.lastIndexOf('.');
        if(p >= 0) {
            tempModule = tempModule + "." + tempName.substring(0, p); //$NON-NLS-1$
            tempName = tempName.substring(p+1);
        }
        this.name = tempName;
        this.module = tempModule;
        this.documentation = value.getDocumentation();
        this.content = name + " :: " + value.getType() + "  (" + module + ")"; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
        this.replacementOffset = replacementOffset;
        this.prefix = prefix;
//        System.out.println(prefix);
        if (value.isPrivate())
            this.completionType = SCLCompletionType.PRIVATE;
        else
            this.completionType = SCLCompletionType.PUBLIC;
    }

    public SCLCompletionProposal(String name, String module, SCLCompletionType completionType, int replacementOffset, String prefix) {
        this.name = name;
        this.module = module;
        this.content = name + " (" + module + ")"; //$NON-NLS-1$ //$NON-NLS-2$
        this.documentation = null;
        this.replacementOffset = replacementOffset;
        this.prefix = prefix;
        this.completionType = completionType;
    }

    @Override
    public void apply(IDocument document) {

    }

    @Override
    public Point getSelection(IDocument document) {
        return new Point(replacementOffset + getName().length(), 0);
    }

    @Override
    public String getAdditionalProposalInfo() {
        return documentation;
    }

    @Override
    public String getDisplayString() {
        return content;
    }

    @Override
    public Image getImage() {
        switch (completionType) {
        case PRIVATE:
            return PRIVATE;
        case PUBLIC:
            return PUBLIC;
        case CONST:
            return CONST;
        case TYPE:
            return TYPE;
        default:
            return null;
        }
    }

    @Override
    public IContextInformation getContextInformation() {
        return null;
    }

    @Override
    public void apply(IDocument document, char trigger, int offset) {
    }

    @Override
    public boolean isValidFor(IDocument document, int offset) {
        return validate(document, offset, null);
    }

    @Override
    public char[] getTriggerCharacters() {
        return null;
    }

    @Override
    public int getContextInformationPosition() {
        return 0;
    }

    @Override
    public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {
        try {
//            String replacement = getName().substring(offset - replacementOffset);
            IDocument doc = viewer.getDocument();
            Point p = viewer.getSelectedRange();
//            System.out.println("selectedRange : " + p);
//            System.out.println("prefix : " + prefix);
//            int start = offset - prefix.length();
//            int end = prefix.length();
//            System.out.println("start : " + start + ", end : " + end);
//            String sadd = doc.get(start, end);
//            System.out.println("toReplace : " + sadd);
            if (p.y > 0) {
                doc.replace(p.x, p.y, ""); //$NON-NLS-1$
                doc.replace(offset, 0, getName());
            } else {
                String currentText = doc.get(offset - prefix.length(), prefix.length());
                if (currentText.equals(getName()))
                    return;
                doc.replace(offset - prefix.length(), prefix.length(), ""); //$NON-NLS-1$
                doc.replace(offset - prefix.length(), 0, getName());
            }
        } catch (BadLocationException x) {
            x.printStackTrace();
        }
    }

    @Override
    public void selected(ITextViewer viewer, boolean smartToggle) {
    }

    @Override
    public void unselected(ITextViewer viewer) {
    }

    @Override
    public boolean validate(IDocument document, int offset, DocumentEvent event) {
        try {
            String n = getName();
            //System.out.println(n + " (" + n.length() + ") " + replacementOffset + " " + offset);
            boolean a = offset >= replacementOffset;
            boolean b = offset <= replacementOffset + n.length();
            String s = document.get(replacementOffset, offset - replacementOffset);
            prefix = s;
            //System.out.println("prefix: " + s + " - " + prefix);
            boolean c = n.toLowerCase().startsWith(s.toLowerCase());
            //System.out.println("matches: " + a + " " + b + " " + c);
            return a && b && c;
        } catch (BadLocationException x) {
            //x.printStackTrace();
            return false;
        }
    }

    @Override
    public IInformationControlCreator getInformationControlCreator() {
        return CREATOR;
    }
    
    private static final IInformationControlCreator CREATOR = new IInformationControlCreator() {
        
        @Override
        public IInformationControl createInformationControl(Shell parent) {
            return new DefaultInformationControl(parent);
        }
    };

    @Override
    public CharSequence getPrefixCompletionText(IDocument document, int completionOffset) {
        return getName();
    }

    @Override
    public int getPrefixCompletionStart(IDocument document, int completionOffset) {
        return replacementOffset - prefix.length();
    }

    @Override
    public boolean isAutoInsertable() {
        return true;
    }

    @Override
    public Object getAdditionalProposalInfo(IProgressMonitor monitor) {
        return documentation;
    }

    public String getName() {
        return name;
    }
    
    public boolean isPrivate() {
        return SCLCompletionType.PRIVATE == completionType;
    }

    public String getModule() {
        return module;
    }
}