/*
 * [The "BSD license"]
 *  Copyright (c) 2011 Terence Parr
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.stringtemplate.v4.gui;

import org.antlr.runtime.CommonToken;
import org.antlr.runtime.tree.CommonTree;
import org.antlr.runtime.tree.CommonTreeAdaptor;
import org.stringtemplate.v4.InstanceScope;
import org.stringtemplate.v4.Interpreter;
import org.stringtemplate.v4.ST;
import org.stringtemplate.v4.STGroup;
import org.stringtemplate.v4.STGroupFile;
import org.stringtemplate.v4.STGroupString;
import org.stringtemplate.v4.debug.EvalExprEvent;
import org.stringtemplate.v4.debug.EvalTemplateEvent;
import org.stringtemplate.v4.debug.InterpEvent;
import org.stringtemplate.v4.misc.ErrorManager;
import org.stringtemplate.v4.misc.Interval;
import org.stringtemplate.v4.misc.Misc;
import org.stringtemplate.v4.misc.STMessage;
import org.stringtemplate.v4.misc.STRuntimeMessage;

import javax.swing.*;
import javax.swing.border.Border;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultHighlighter;
import javax.swing.text.Highlighter;
import javax.swing.text.JTextComponent;
import javax.swing.tree.TreePath;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

public class STViz {
    protected static final String WINDOWS_LINE_ENDINGS = "WINDOWS_LINE_ENDINGS";

    //public ST currentST; // current ST selected in template tree
    public EvalTemplateEvent root;
    public InterpEvent currentEvent;
    public InstanceScope currentScope;
    public List<InterpEvent> allEvents;
    public JTreeSTModel tmodel;
    public ErrorManager errMgr;
    public Interpreter interp;
    public String output;
    public List<String> trace;
    public List<STMessage> errors;

    public STViewFrame viewFrame;

    private final AtomicInteger updateDepth = new AtomicInteger();

    public STViz(ErrorManager errMgr,
                 EvalTemplateEvent root,
                 String output,
                 Interpreter interp,
                 List<String> trace,
                 List<STMessage> errors)
    {
        this.errMgr = errMgr;
        this.currentEvent = root;
        this.currentScope = root.scope;
        this.output = output;
        this.interp = interp;
        this.allEvents = interp.getEvents();
        this.trace = trace;
        this.errors = errors;
    }

    public void open() {
        viewFrame = new STViewFrame();
        updateStack(currentScope, viewFrame);
        updateAttributes(currentScope, viewFrame);

        List<InterpEvent> events = currentScope.events;
        tmodel = new JTreeSTModel(interp, (EvalTemplateEvent)events.get(events.size()-1));
        viewFrame.tree.setModel(tmodel);
        viewFrame.tree.addTreeSelectionListener(
            new TreeSelectionListener() {
                @Override
                public void valueChanged(TreeSelectionEvent treeSelectionEvent) {
                    int depth = updateDepth.incrementAndGet();
                    try {
                        if (depth != 1) {
                            return;
                        }

                        currentEvent = ((JTreeSTModel.Wrapper)viewFrame.tree.getLastSelectedPathComponent()).event;
                        currentScope = currentEvent.scope;
                        updateCurrentST(viewFrame);
                    }
                    finally {
                        updateDepth.decrementAndGet();
                    }
                }
            }
        );

        JTreeASTModel astModel = new JTreeASTModel(new CommonTreeAdaptor(), currentScope.st.impl.ast);
        viewFrame.ast.setModel(astModel);
        viewFrame.ast.addTreeSelectionListener(
            new TreeSelectionListener() {
                @Override
                public void valueChanged(TreeSelectionEvent treeSelectionEvent) {
                    int depth = updateDepth.incrementAndGet();
                    try {
                        if (depth != 1) {
                            return;
                        }

                        TreePath path = treeSelectionEvent.getNewLeadSelectionPath();
                        if ( path==null ) return;
                        CommonTree node = (CommonTree)treeSelectionEvent.getNewLeadSelectionPath().getLastPathComponent();
                        //System.out.println("select AST: "+node);
                        CommonToken a = (CommonToken)currentScope.st.impl.tokens.get(node.getTokenStartIndex());
                        CommonToken b = (CommonToken)currentScope.st.impl.tokens.get(node.getTokenStopIndex());
                        highlight(viewFrame.template, a.getStartIndex(), b.getStopIndex());
                    }
                    finally {
                        updateDepth.decrementAndGet();
                    }
                }
            }
        );

        // Track selection of attr but do nothing for now
//        viewFrame.attributes.addListSelectionListener(
//            new ListSelectionListener() {
//                public void valueChanged(ListSelectionEvent e) {
//                    int minIndex = viewFrame.attributes.getMinSelectionIndex();
//                    int maxIndex = viewFrame.attributes.getMaxSelectionIndex();
//                    for (int i = minIndex; i <= maxIndex; i++) {
//                        if (viewFrame.attributes.isSelectedIndex(i)) {
//                            //System.out.println("index="+i);
//                        }
//                    }
//                }
//            }
//        );

        CaretListener caretListenerLabel = new CaretListener() {
            @Override
            public void caretUpdate(CaretEvent e) {
                int depth = updateDepth.incrementAndGet();
                try {
                    if (depth != 1) {
                        return;
                    }

                    int dot = toEventPosition((JTextComponent)e.getSource(), e.getDot());
                    currentEvent = findEventAtOutputLocation(allEvents, dot);
                    if ( currentEvent==null ) currentScope = tmodel.root.event.scope;
                    else currentScope = currentEvent.scope;

                    // update tree view of template hierarchy
                    // compute path from root to currentST, create TreePath for tree widget
                    List<EvalTemplateEvent> stack = Interpreter.getEvalTemplateEventStack(currentScope, true);
                    //System.out.println("\nselect path="+stack);
                    Object[] path = new Object[stack.size()];
                    int j = 0;
                    for (EvalTemplateEvent s : stack) {
                        path[j++] = new JTreeSTModel.Wrapper(s);
                    }
                    TreePath p = new TreePath(path);
                    viewFrame.tree.setSelectionPath(p);
                    viewFrame.tree.scrollPathToVisible(p);
                    updateCurrentST(viewFrame);
                }
                finally {
                    updateDepth.decrementAndGet();
                }
            }
        };

        viewFrame.output.addCaretListener(caretListenerLabel);

        // ADD ERRORS
        if ( errors==null || errors.size()==0 ) {
            viewFrame.errorScrollPane.setVisible(false); // don't show unless errors
        }
        else {
            final DefaultListModel errorListModel = new DefaultListModel();
            for (STMessage msg : errors) {
                errorListModel.addElement(msg);
            }
            viewFrame.errorList.setModel(errorListModel);
        }

        viewFrame.errorList.addListSelectionListener(
            new ListSelectionListener() {
                @Override
                public void valueChanged(ListSelectionEvent e) {
                    int depth = updateDepth.incrementAndGet();
                    try {
                        if (depth != 1) {
                            return;
                        }

                        int minIndex = viewFrame.errorList.getMinSelectionIndex();
                        int maxIndex = viewFrame.errorList.getMaxSelectionIndex();
                        int i = minIndex;
                        while ( i <= maxIndex ) {
                            if (viewFrame.errorList.isSelectedIndex(i)) break;
                            i++;
                        }
                        ListModel model = viewFrame.errorList.getModel();
                        STMessage msg = (STMessage)model.getElementAt(i);
                        if ( msg instanceof STRuntimeMessage ) {
                            STRuntimeMessage rmsg = (STRuntimeMessage)msg;
                            Interval I = rmsg.self.impl.sourceMap[rmsg.ip];
                            currentEvent = null;
                            currentScope = ((STRuntimeMessage) msg).scope;
                            updateCurrentST(viewFrame);
                            if ( I!=null ) { // highlight template
                                highlight(viewFrame.template, I.a, I.b);
                            }
                        }
                    }
                    finally {
                        updateDepth.decrementAndGet();
                    }
                }
            }
        );

        Border empty = BorderFactory.createEmptyBorder();
        viewFrame.treeContentSplitPane.setBorder(empty);
        viewFrame.outputTemplateSplitPane.setBorder(empty);
        viewFrame.templateBytecodeTraceTabPanel.setBorder(empty);
        viewFrame.treeAttributesSplitPane.setBorder(empty);


        viewFrame.treeContentSplitPane.setOneTouchExpandable(true);
        viewFrame.outputTemplateSplitPane.setOneTouchExpandable(true);
        viewFrame.treeContentSplitPane.setDividerSize(10);
        viewFrame.outputTemplateSplitPane.setDividerSize(8);
        viewFrame.treeContentSplitPane.setContinuousLayout(true);
        viewFrame.treeAttributesSplitPane.setContinuousLayout(true);
        viewFrame.outputTemplateSplitPane.setContinuousLayout(true);

        viewFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        viewFrame.pack();
        viewFrame.setSize(900, 700);

        setText(viewFrame.output, output);
        setText(viewFrame.template, currentScope.st.impl.template);
        setText(viewFrame.bytecode, currentScope.st.impl.disasm());
        setText(viewFrame.trace, Misc.join(trace.iterator(), "\n"));

        viewFrame.setVisible(true);
    }

    public void waitForClose() throws InterruptedException {
        final Object lock = new Object();

        Thread t = new Thread() {
            @Override
            public void run() {
                synchronized (lock) {
                    while (viewFrame.isVisible()) {
                        try {
                            lock.wait();
                        } catch (InterruptedException e) {
                        }
                    }
                }
            }
        };

        t.start();

        viewFrame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent arg0) {
                synchronized (lock) {
                    viewFrame.setVisible(false);
                    lock.notify();
                }
            }
        });

        t.join();
    }

    private void updateCurrentST(STViewFrame m) {
//      System.out.println("updateCurrentST(): currentScope.st="+currentScope.st);
        // update all views according to currentScope.st
        updateStack(currentScope, m);                      // STACK
        updateAttributes(currentScope, m);                 // ATTRIBUTES
        setText(m.bytecode, currentScope.st.impl.disasm()); // BYTECODE DIS.
        setText(m.template, currentScope.st.impl.template); // TEMPLATE SRC
        JTreeASTModel astModel = new JTreeASTModel(new CommonTreeAdaptor(), currentScope.st.impl.ast);
        viewFrame.ast.setModel(astModel);

        // highlight output text and, if {...} subtemplate, region in ST src
        // get last event for currentScope.st; it's the event that captures ST eval
        if (currentEvent instanceof EvalExprEvent) {
            EvalExprEvent exprEvent = (EvalExprEvent)currentEvent;
            highlight(m.output, exprEvent.outputStartChar, exprEvent.outputStopChar);
            highlight(m.template, exprEvent.exprStartChar, exprEvent.exprStopChar);
        }
        else {
            EvalTemplateEvent templateEvent;
            if (currentEvent instanceof EvalTemplateEvent) {
                templateEvent = (EvalTemplateEvent)currentEvent;
            }
            else {
                List<InterpEvent> events = currentScope.events;
                templateEvent = (EvalTemplateEvent)events.get(events.size() - 1);
            }

            if (templateEvent != null) {
                highlight(m.output, templateEvent.outputStartChar, templateEvent.outputStopChar);
            }

            if ( currentScope.st.isAnonSubtemplate() ) {
                Interval r = currentScope.st.impl.getTemplateRange();
                //System.out.println("currentScope.st src range="+r);
                //m.template.moveCaretPosition(r.a);
                highlight(m.template, r.a, r.b);
            }
        }
    }

    protected void setText(JEditorPane component, String text) {
        List<Integer> windowsLineEndingsList = new ArrayList<Integer>();
        for (int i = 0; i < text.length(); i += 2) {
            i = text.indexOf("\r\n", i);
            if (i < 0) {
                break;
            }

            windowsLineEndingsList.add(i);
        }

        int[] windowsLineEndings = new int[windowsLineEndingsList.size()];
        for (int i = 0; i < windowsLineEndingsList.size(); i++) {
            windowsLineEndings[i] = windowsLineEndingsList.get(i);
        }

        component.setText(text);
        component.getDocument().putProperty(WINDOWS_LINE_ENDINGS, windowsLineEndings);
    }

    protected int toComponentPosition(JTextComponent component, int position) {
        int[] windowsLineEndings = (int[])component.getDocument().getProperty(WINDOWS_LINE_ENDINGS);
        if (windowsLineEndings == null || windowsLineEndings.length == 0) {
            return position;
        }

        int index = Arrays.binarySearch(windowsLineEndings, position);
        if (index >= 0) {
            return position - index;
        }

        return position - (-index - 1);
    }

    protected int toEventPosition(JTextComponent component, int position) {
        int result = position;
        while (toComponentPosition(component, result) < position) {
            result++;
        }

        return result;
    }

    protected final void highlight(JTextComponent comp, int i, int j) {
        highlight(comp, i, j, true);
    }

    protected void highlight(JTextComponent comp, int i, int j, boolean scroll) {
        Highlighter highlighter = comp.getHighlighter();
        highlighter.removeAllHighlights();

        try {
            i = toComponentPosition(comp, i);
            j = toComponentPosition(comp, j);
            highlighter.addHighlight(i, j+1, DefaultHighlighter.DefaultPainter);
            if (scroll) {
                if (comp.getCaretPosition() < i || comp.getCaretPosition() > j) {
                    comp.moveCaretPosition(i);
                    comp.scrollRectToVisible(comp.modelToView(i));
                }
            }
        }
        catch (BadLocationException ble) {
            errMgr.internalError(tmodel.root.event.scope.st, "bad highlight location", ble);
        }
    }

    protected void updateAttributes(final InstanceScope scope, final STViewFrame m) {
        //System.out.println("updateAttributes: "+Interpreter.getEnclosingInstanceStackString(scope) );
        m.attributes.setModel( new JTreeScopeStackModel(scope) );
        m.attributes.setRootVisible(false);
        m.attributes.setShowsRootHandles(true);
        //System.out.println("add events="+ st.addAttrEvents);
//      ST st = scope.st;
//      final DefaultListModel attrModel = new DefaultListModel();
//      final Map<String,Object> attrs = st.getAttributes();
//      if ( attrs!=null ) {
//          for (String a : attrs.keySet()) {
//              if ( st.debugState!=null && st.debugState.addAttrEvents!=null ) {
//                  List<AddAttributeEvent> events = st.debugState.addAttrEvents.get(a);
//                  StringBuilder locations = new StringBuilder();
//                  int i = 0;
//                  if ( events!=null ) {
//                      for (AddAttributeEvent ae : events) {
//                          if ( i>0 ) locations.append(", ");
//                          locations.append(ae.getFileName()+":"+ae.getLine());
//                          i++;
//                      }
//                  }
//                  if ( locations.length()>0 ) {
//                      attrModel.addElement(a+" = "+attrs.get(a)+" @ "+locations.toString());
//                  }
//                  else {
//                      attrModel.addElement(a+" = "+attrs.get(a));
//                  }
//              }
//              else {
//                  attrModel.addElement(a+" = "+attrs.get(a));
//              }
//          }
//      }
//      m.attributes.setModel(attrModel);
    }

    protected void updateStack(InstanceScope scope, STViewFrame m) {
        List<ST> stack = Interpreter.getEnclosingInstanceStack(scope, true);
        m.setTitle("STViz - ["+ Misc.join(stack.iterator()," ")+"]");
//        // also do source stack
//        StackTraceElement[] trace = st.newSTEvent.stack.getStackTrace();
//        StringWriter sw = new StringWriter();
//        for (StackTraceElement e : trace) {
//            sw.write(e.toString()+"\n");
//        }
    }

    public InterpEvent findEventAtOutputLocation(List<InterpEvent> events,
                                                 int charIndex)
    {
        for (InterpEvent e : events) {
            if (e.scope.earlyEval) {
                continue;
            }

            if ( charIndex>=e.outputStartChar && charIndex<=e.outputStopChar) return e;
        }
        return null;
    }

    public static void main(String[] args) throws IOException { // test rig
        if ( args.length>0 && args[0].equals("1") ) test1();
        else if ( args.length>0 && args[0].equals("2") ) test2();
        else if ( args.length>0 && args[0].equals("3") ) test3();
        else if ( args.length>0 && args[0].equals("4") ) test4();
    }

    public static void test1() throws IOException { // test rig
        String templates =
            "method(type,name,locals,args,stats) ::= <<\n" +
            "public <type> <name>(<args:{a| int <a>}; separator=\", \">) {\n" +
            "    <if(locals)>int locals[<locals>];<endif>\n"+
            "    <stats;separator=\"\\n\">\n" +
            "}\n" +
            ">>\n"+
            "assign(a,b) ::= \"<a> = <b>;\"\n"+
            "return(x) ::= <<return <x>;>>\n" +
            "paren(x) ::= \"(<x>)\"\n";

        String tmpdir = System.getProperty("java.io.tmpdir");
        writeFile(tmpdir, "t.stg", templates);
        STGroup group = new STGroupFile(tmpdir+"/"+"t.stg");
        ST st = group.getInstanceOf("method");
        st.impl.dump();
        st.add("type", "float");
        st.add("name", "foo");
        st.add("locals", 3);
        st.add("args", new String[] {"x", "y", "z"});
        ST s1 = group.getInstanceOf("assign");
        ST paren = group.getInstanceOf("paren");
        paren.add("x", "x");
        s1.add("a", paren);
        s1.add("b", "y");
        ST s2 = group.getInstanceOf("assign");
        s2.add("a", "y");
        s2.add("b", "z");
        ST s3 = group.getInstanceOf("return");
        s3.add("x", "3.14159");
        st.add("stats", s1);
        st.add("stats", s2);
        st.add("stats", s3);

        STViz viz = st.inspect();
        System.out.println(st.render()); // should not mess up ST event lists
    }

    public static void test2() throws IOException { // test rig
        String templates =
            "t1(q1=\"Some\\nText\") ::= <<\n" +
            "<q1>\n" +
            ">>\n" +
            "\n" +
            "t2(p1) ::= <<\n" +
            "<p1>\n" +
            ">>\n" +
            "\n" +
            "main() ::= <<\n" +
            "START-<t1()>-END\n" +
            "\n" +
            "START-<t2(p1=\"Some\\nText\")>-END\n" +
            ">>\n";

        String tmpdir = System.getProperty("java.io.tmpdir");
        writeFile(tmpdir, "t.stg", templates);
        STGroup group = new STGroupFile(tmpdir+"/"+"t.stg");
        ST st = group.getInstanceOf("main");
        STViz viz = st.inspect();
    }

    public static void test3() throws IOException {
        String templates =
            "main() ::= <<\n" +
            "Foo: <{bar};format=\"lower\">\n" +
            ">>\n";

        String tmpdir = System.getProperty("java.io.tmpdir");
        writeFile(tmpdir, "t.stg", templates);
        STGroup group = new STGroupFile(tmpdir+"/"+"t.stg");
        ST st = group.getInstanceOf("main");
        st.inspect();
    }

    public static void test4() throws IOException {
        String templates =
            "main(t) ::= <<\n" +
            "hi: <t>\n" +
            ">>\n" +
            "foo(x,y={hi}) ::= \"<bar(x,y)>\"\n" +
            "bar(x,y) ::= << <y> >>\n" +
            "ignore(m) ::= \"<m>\"\n";

        STGroup group = new STGroupString(templates);
        ST st = group.getInstanceOf("main");
        ST foo = group.getInstanceOf("foo");
        st.add("t", foo);
        ST ignore = group.getInstanceOf("ignore");
        ignore.add("m", foo); // embed foo twice!
        st.inspect();
        st.render();
    }

    public static void writeFile(String dir, String fileName, String content) {
        try {
            File f = new File(dir, fileName);
            if ( !f.getParentFile().exists() ) f.getParentFile().mkdirs();
            FileWriter w = new FileWriter(f);
            BufferedWriter bw = new BufferedWriter(w);
            bw.write(content);
            bw.close();
            w.close();
        }
        catch (IOException ioe) {
            System.err.println("can't write file");
            ioe.printStackTrace(System.err);
        }
    }
}
