/***** BEGIN LICENSE BLOCK *****
 * Version: EPL 2.0/GPL 2.0/LGPL 2.1
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 * The contents of this file are subject to the Eclipse Public
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 * except in compliance with the License. You may obtain a copy of
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 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
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 * Copyright (C) 2001 Alan Moore <alan_moore@gmx.net>
 * Copyright (C) 2001-2004 Jan Arne Petersen <jpetersen@uni-bonn.de>
 * Copyright (C) 2002 Benoit Cerrina <b.cerrina@wanadoo.fr>
 * Copyright (C) 2002-2004 Anders Bengtsson <ndrsbngtssn@yahoo.se>
 * Copyright (C) 2004 Thomas E Enebo <enebo@acm.org>
 * Copyright (C) 2004 Joey Gibson <joey@joeygibson.com>
 * Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
 * Copyright (C) 2005 Charles O Nutter <headius@headius.com>
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package org.jruby.exceptions;

import java.io.PrintWriter;
import java.io.StringWriter;

import java.lang.reflect.Member;
import org.jruby.NativeException;
import org.jruby.Ruby;
import org.jruby.RubyClass;
import org.jruby.RubyException;
import org.jruby.RubyInstanceConfig;
import org.jruby.RubyString;
import org.jruby.runtime.Helpers;
import org.jruby.runtime.RubyEvent;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.backtrace.RubyStackTraceElement;
import org.jruby.runtime.backtrace.TraceType;
import org.jruby.runtime.builtin.IRubyObject;

public class RaiseException extends JumpException {
    public static final boolean DEBUG = false;
    private static final long serialVersionUID = -7612079169559973951L;

    private RubyException exception;
    private String providedMessage;
    private boolean nativeException;

    /**
     * Construct a new RaiseException to wrap the given Ruby exception for Java-land
     * throwing purposes.
     *
     * This constructor will generate a backtrace using the Java
     * stack trace and the interpreted Ruby frames for the current thread.
     *
     * @param actException The Ruby exception to wrap
     */
    public RaiseException(RubyException actException) {
        this(actException, false);
    }

    /**
     * Construct a new RaiseException to wrap the given Ruby exception for Java-land
     * throwing purposes.
     *
     * This constructor will not generate a backtrace and will instead use the
     * one specified by the
     *
     * @param exception The Ruby exception to wrap
     * @param backtrace
     */
    public RaiseException(RubyException exception, IRubyObject backtrace) {
        super(exception.getMessageAsJavaString());
        if (DEBUG) {
            Thread.dumpStack();
        }
        setException(exception, false);
        preRaise(exception.getRuntime().getCurrentContext(), backtrace);
    }

    public RaiseException(Ruby runtime, RubyClass excptnClass, String msg, boolean nativeException) {
        super(msg);
        if (msg == null) {
            msg = "No message available";
        }
        providedMessage = '(' + excptnClass.getName() + ") " + msg;
        this.nativeException = nativeException;
        if (DEBUG) {
            Thread.dumpStack();
        }
        final ThreadContext context = runtime.getCurrentContext();
        setException((RubyException) Helpers.invoke(
                context,
                excptnClass,
                "new",
                RubyString.newUnicodeString(runtime, msg)),
                nativeException);
        preRaise(context);
    }

    public RaiseException(Ruby runtime, RubyClass excptnClass, String msg, IRubyObject backtrace, boolean nativeException) {
        super(msg);
        if (msg == null) {
            msg = "No message available";
        }
        providedMessage = '(' + excptnClass.getName() + ") " + msg;
        this.nativeException = nativeException;
        if (DEBUG) {
            Thread.dumpStack();
        }
        final ThreadContext context = runtime.getCurrentContext();
        setException((RubyException) Helpers.invoke(
                context,
                excptnClass,
                "new",
                RubyString.newUnicodeString(runtime, msg)),
                nativeException);
        preRaise(context, backtrace);
    }

    public RaiseException(RubyException exception, boolean nativeException) {
        super(exception.getMessageAsJavaString());
        if (DEBUG) {
            Thread.dumpStack();
        }
        this.nativeException = nativeException;
        setException(exception, nativeException);
        preRaise(exception.getRuntime().getCurrentContext());
    }

    public RaiseException(Throwable cause, NativeException nativeException) {
        super(nativeException.getMessageAsJavaString(), cause);
        providedMessage = super.getMessage(); // cause.getClass().getName() + ": " + message
        setException(nativeException, true);
        preRaise(nativeException.getRuntime().getCurrentContext(), nativeException.getCause().getStackTrace());
        setStackTrace(RaiseException.javaTraceFromRubyTrace(exception.getBacktraceElements()));
    }

    @Deprecated
    public static RaiseException createNativeRaiseException(Ruby runtime, Throwable cause) {
        return createNativeRaiseException(runtime, cause, null);
    }

    @Deprecated
    public static RaiseException createNativeRaiseException(Ruby runtime, Throwable cause, Member target) {
        NativeException nativeException = new NativeException(runtime, runtime.getNativeException(), cause);

        // FIXME: someday, add back filtering of reflection/handle methods between JRuby and target

        return new RaiseException(cause, nativeException);
    }

    @Override
    public String getMessage() {
        if (providedMessage == null) {
            providedMessage = '(' + exception.getMetaClass().getBaseName() + ") " + exception.message(exception.getRuntime().getCurrentContext()).asJavaString();
        }
        return providedMessage;
    }

    /**
     * Gets the exception
     * @return Returns a RubyException
     */
    public final RubyException getException() {
        return exception;
    }

    private void preRaise(ThreadContext context) {
        preRaise(context, (IRubyObject) null);
    }

    private void preRaise(ThreadContext context, StackTraceElement[] javaTrace) {
        context.runtime.incrementExceptionCount();
        doSetLastError(context);
        doCallEventHook(context);

        if (RubyInstanceConfig.LOG_EXCEPTIONS) TraceType.logException(exception);

        if (requiresBacktrace(context)) {
            exception.prepareIntegratedBacktrace(context, javaTrace);
        }
    }

    private boolean requiresBacktrace(ThreadContext context) {
        IRubyObject debugMode;
        // We can only omit backtraces of descendents of Standard error for 'foo rescue nil'
        return context.exceptionRequiresBacktrace ||
                ((debugMode = context.runtime.getGlobalVariables().get("$DEBUG")) != null && debugMode.isTrue()) ||
                ! context.runtime.getStandardError().isInstance(exception);
    }

    private void preRaise(ThreadContext context, IRubyObject backtrace) {
        context.runtime.incrementExceptionCount();
        doSetLastError(context);
        doCallEventHook(context);

        if (RubyInstanceConfig.LOG_EXCEPTIONS) TraceType.logException(exception);

        // We can only omit backtraces of descendents of Standard error for 'foo rescue nil'
        if (requiresBacktrace(context)) {
            if (backtrace == null) {
                exception.prepareBacktrace(context, nativeException);
            } else {
                exception.forceBacktrace(backtrace);
                if ( backtrace.isNil() ) return;
            }

            // call Throwable.setStackTrace so that when RaiseException appears nested inside another exception,
            // Ruby stack trace gets displayed
            // JRUBY-2673: if wrapping a NativeException, use the actual Java exception's trace as our Java trace
            if (exception instanceof NativeException) {
                setStackTrace(((NativeException) exception).getCause().getStackTrace());
            } else {
                setStackTrace(RaiseException.javaTraceFromRubyTrace(exception.getBacktraceElements()));
            }
        }
    }

    private static void doCallEventHook(final ThreadContext context) {
        if (context.runtime.hasEventHooks()) {
            context.runtime.callEventHooks(context, RubyEvent.RAISE, context.getFile(), context.getLine(), context.getFrameName(), context.getFrameKlazz());
        }
    }

    private void doSetLastError(final ThreadContext context) {
        context.runtime.getGlobalVariables().set("$!", exception);
    }

    /**
     * Sets the exception
     * @param newException The exception to set
     */
    protected final void setException(RubyException newException, boolean nativeException) {
        this.exception = newException;
        this.nativeException = nativeException;
    }

    public static StackTraceElement[] javaTraceFromRubyTrace(RubyStackTraceElement[] trace) {
        StackTraceElement[] newTrace = new StackTraceElement[trace.length];
        for (int i = 0; i < newTrace.length; i++) {
            newTrace[i] = trace[i].asStackTraceElement();
        }
        return newTrace;
    }
}
