/**
 * Copyright (c) 2005-2013 by Appcelerator, Inc. All Rights Reserved.
 * Licensed under the terms of the Eclipse Public License (EPL).
 * Please see the license.txt included with this distribution for details.
 * Any modifications to this file must keep this entire header intact.
 */
package org.python.pydev.debug.model;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.eclipse.core.runtime.IPath;
import org.python.pydev.core.IInterpreterManager;
import org.python.pydev.core.IPythonNature;
import org.python.pydev.core.IToken;
import org.python.pydev.debug.core.ConfigureExceptionsFileUtils;
import org.python.pydev.debug.core.PydevDebugPlugin;
import org.python.pydev.debug.core.PydevDebugPreferencesInitializer;
import org.python.pydev.shared_core.callbacks.ListenerList;
import org.python.pydev.shared_core.string.StringUtils;
import org.python.pydev.ui.interpreters.ChooseInterpreterManager;

public class PyExceptionBreakPointManager {

    //Static variables
    private static final String EXCEPTION_FILE_NAME = "python_exceptions.prefs";
    private static final String CUSTOM_EXCEPTION_FILE_NAME = "custom_exceptions.prefs";
    private static final String BREAK_ON_CAUGHT_EXCEPTION = "caught_exception_state.prefs";
    private static final String BREAK_ON_UNCAUGHT_EXCEPTION = "uncaught_exception_state.prefs";

    private static PyExceptionBreakPointManager pyExceptionBreakPointManager;
    private static final Object lock = new Object();

    //For instance
    /*default*/ListenerList<IExceptionsBreakpointListener> listeners = new ListenerList<IExceptionsBreakpointListener>(
            IExceptionsBreakpointListener.class);

    public final IgnoreCaughtExceptionsWhenThrownFrom ignoreCaughtExceptionsWhenThrownFrom = new IgnoreCaughtExceptionsWhenThrownFrom(
            this);

    /**
     * Singleton: private constructor.
     */
    private PyExceptionBreakPointManager() {

    }

    public static PyExceptionBreakPointManager getInstance() {
        if (pyExceptionBreakPointManager == null) {
            synchronized (lock) {
                if (pyExceptionBreakPointManager == null) {
                    pyExceptionBreakPointManager = new PyExceptionBreakPointManager();
                }
            }
        }
        return pyExceptionBreakPointManager;
    }

    //Listeners

    public void addListener(IExceptionsBreakpointListener listener) {
        this.listeners.add(listener);
    }

    public void removeListener(IExceptionsBreakpointListener listener) {
        this.listeners.remove(listener);
    }

    //Setters

    /**
     * Sets whether we should break on caught/uncaught exceptions and the array of exceptions to be used.
     */
    public void setBreakOn(boolean breakOnCaught, boolean breakOnUncaught, String[] exceptionArray) {
        ConfigureExceptionsFileUtils.writeToFile(BREAK_ON_CAUGHT_EXCEPTION, Boolean.toString(breakOnCaught), false);

        ConfigureExceptionsFileUtils.writeToFile(BREAK_ON_UNCAUGHT_EXCEPTION, Boolean.toString(breakOnUncaught), false);

        String pyExceptionsStr = StringUtils.join(
                ConfigureExceptionsFileUtils.DELIMITER, exceptionArray);

        ConfigureExceptionsFileUtils.writeToFile(EXCEPTION_FILE_NAME, pyExceptionsStr, false);

        for (IExceptionsBreakpointListener listener : this.listeners.getListeners()) {
            listener.onSetConfiguredExceptions();
        }
    }

    /**
     * Adds a new custom exception the user entered (note that it just adds it to the list
     * of custom exceptions, it doesn't really change the exceptions set). 
     */
    public void addUserConfiguredException(String userConfiguredException) {
        boolean isAppend = false;

        IPath path = ConfigureExceptionsFileUtils.getFilePathFromMetadata(CUSTOM_EXCEPTION_FILE_NAME);
        if (path.toFile().exists()) {
            isAppend = true;
            userConfiguredException = ConfigureExceptionsFileUtils.DELIMITER + userConfiguredException;
        }
        ConfigureExceptionsFileUtils.writeToFile(CUSTOM_EXCEPTION_FILE_NAME, userConfiguredException, isAppend);
    }

    //Getters

    public boolean getBreakOnUncaughtExceptions() {
        String breakOnUncaught = ConfigureExceptionsFileUtils.readFromMetadataFile(BREAK_ON_UNCAUGHT_EXCEPTION);
        if (breakOnUncaught.length() > 0) {
            return Boolean.parseBoolean(breakOnUncaught);
        } else {
            return false;
        }
    }

    public boolean getBreakOnCaughtExceptions() {
        String breakOnCaught = ConfigureExceptionsFileUtils.readFromMetadataFile(BREAK_ON_CAUGHT_EXCEPTION);
        if (breakOnCaught.length() > 0) {
            return Boolean.parseBoolean(breakOnCaught);
        } else {
            return false;
        }
    }

    public String getExceptionsString() {
        return ConfigureExceptionsFileUtils.readFromMetadataFile(EXCEPTION_FILE_NAME);
    }

    public List<String> getExceptionsList() {
        return ConfigureExceptionsFileUtils.getConfiguredExceptions(EXCEPTION_FILE_NAME);
    }

    /**
     * @return only the exceptions configured by the user (i.e.: not builtin exceptions)
     */
    public List<String> getUserConfiguredExceptions() {
        List<String> configuredExceptions = ConfigureExceptionsFileUtils
                .getConfiguredExceptions(CUSTOM_EXCEPTION_FILE_NAME);
        Collections.sort(configuredExceptions);

        return configuredExceptions;
    }

    /**
     * @return a list the default 'builtin' exceptions to be presented to the user (i.e.:
     * AssertionError, RuntimeError, etc)
     */
    public List<String> getBuiltinExceptions() {
        ArrayList<String> list = new ArrayList<String>();
        IInterpreterManager useManager = ChooseInterpreterManager.chooseInterpreterManager();
        if (useManager != null) {
            IToken[] pythonTokens = useManager.getBuiltinMod(IPythonNature.DEFAULT_INTERPRETER).getGlobalTokens();
            for (IToken token : pythonTokens) {
                String pyToken = token.getRepresentation();
                String lower = pyToken.toLowerCase();
                if (lower.contains("error") || lower.contains("exception") || lower.contains("warning")) {
                    list.add(pyToken.trim());
                }
            }
            Collections.sort(list);
        }
        return list;
    }

    public boolean getSkipCaughtExceptionsInSameFunction() {
        return PydevDebugPlugin.getDefault().getPreferenceStore()
                .getBoolean(PydevDebugPreferencesInitializer.SKIP_CAUGHT_EXCEPTIONS_IN_SAME_FUNCTION);
    }

    public void setSkipCaughtExceptionsInSameFunction(boolean b) {
        PydevDebugPlugin.getDefault().getPreferenceStore()
                .setValue(PydevDebugPreferencesInitializer.SKIP_CAUGHT_EXCEPTIONS_IN_SAME_FUNCTION, b);
    }

    public boolean getIgnoreExceptionsThrownInLinesWithIgnoreException() {
        return PydevDebugPlugin.getDefault().getPreferenceStore()
                .getBoolean(PydevDebugPreferencesInitializer.IGNORE_EXCEPTIONS_THROWN_IN_LINES_WITH_IGNORE_EXCEPTION);
    }

    public void setIgnoreExceptionsThrownInLinesWithIgnoreException(
            boolean b) {
        PydevDebugPlugin.getDefault().getPreferenceStore()
                .setValue(PydevDebugPreferencesInitializer.IGNORE_EXCEPTIONS_THROWN_IN_LINES_WITH_IGNORE_EXCEPTION, b);
    }

}