# WebResponseWriter.java

    /*
    ** Module   : WebResponseWriter.java
    ** Abstract : Implementation of the builtin class.
    **
    ** Copyright (c) 2019-2023, Golden Code Development Corporation.
    **
    ** -#- -I- --Date-- ---------------------------------------Description----------------------------------------
    ** 001 CA  20190526 First version, stubs taken by converting the skeleton using FWD.
    ** 002 CA  20191024 Added method support levels and updated the class support level.
    ** 003 CA  20210221 Fixed 'qualified', 'extent' and 'returns' annotations at the legacy
    **                  signature.
    ** 004 ME  20210413 Implementation as per OE12.2 - webStream property not implemented.
    **     ME  20210916 Added method to check if in 'webspeed' environment.
    **     CA  20220120 Do not used TypeFactory.object when the OO reference must not be tracked or registered.
    **                  Do not use TypeFactory.object for internal usages, use ObjectVar if the reference must
    **                  be tracked.
    **                  All TypeFactory.object variable definitions must be done outside of the top-level block.
    **     TJD 20220331 Suppress warnings in writeStatusLine
    **     CA  20220923 Variable definitions (including associated with parameters) must be done always outside of
    **                  the BlockManager API.
    **     OM  20221220 Replaced array container with FinalParameterContainer.
    ** 005 CA  20231113 The 'execute' method must be annotated with LegacySignature Type.Execute, and also can be
    **                  dropped if is a no-op.
    */

    /*
    ** This program is free software: you can redistribute it and/or modify
    ** it under the terms of the GNU Affero General Public License as
    ** published by the Free Software Foundation, either version 3 of the
    ** License, or (at your option) any later version.
    **
    ** This program is distributed in the hope that it will be useful,
    ** but WITHOUT ANY WARRANTY; without even the implied warranty of
    ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    ** GNU Affero General Public License for more details.
    **
    ** You may find a copy of the GNU Affero GPL version 3 at the following
    ** location: https://www.gnu.org/licenses/agpl-3.0.en.html
    **
    ** Additional terms under GNU Affero GPL version 3 section 7:
    **
    **   Under Section 7 of the GNU Affero GPL version 3, the following additional
    **   terms apply to the works covered under the License.  These additional terms
    **   are non-permissive additional terms allowed under Section 7 of the GNU
    **   Affero GPL version 3 and may not be removed by you.
    **
    **   0. Attribution Requirement.
    **
    **     You must preserve all legal notices or author attributions in the covered
    **     work or Appropriate Legal Notices displayed by works containing the covered
    **     work.  You may not remove from the covered work any author or developer
    **     credit already included within the covered work.
    **
    **   1. No License To Use Trademarks.
    **
    **     This license does not grant any license or rights to use the trademarks
    **     Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
    **     of Golden Code Development Corporation. You are not authorized to use the
    **     name Golden Code, FWD, or the names of any author or contributor, for
    **     publicity purposes without written authorization.
    **
    **   2. No Misrepresentation of Affiliation.
    **
    **     You may not represent yourself as Golden Code Development Corporation or FWD.
    **
    **     You may not represent yourself for publicity purposes as associated with
    **     Golden Code Development Corporation, FWD, or any author or contributor to
    **     the covered work, without written authorization.
    **
    **   3. No Misrepresentation of Source or Origin.
    **
    **     You may not represent the covered work as solely your work.  All modified
    **     versions of the covered work must be marked in a reasonable way to make it
    **     clear that the modified work is not originating from Golden Code Development
    **     Corporation or FWD.  All modified versions must contain the notices of
    **     attribution required in this license.
    */

    package com.goldencode.p2j.oo.web;

    import com.goldencode.p2j.util.*;
    import com.goldencode.p2j.util.BlockManager.Action;
    import com.goldencode.p2j.util.BlockManager.Condition;
    import com.goldencode.p2j.oo.core.*;
    import com.goldencode.p2j.oo.net.http.Cookie;
    import com.goldencode.p2j.oo.net.http.HttpHeader;
    import com.goldencode.p2j.oo.net.http.HttpHeaderBuilder;
    import com.goldencode.p2j.oo.net.http.TransferEncodingEnum;
    import com.goldencode.p2j.oo.net.http.filter.payload.MessageWriter;
    import com.goldencode.p2j.oo.net.http.filter.writer.BodyWriterBuilder;

    import static com.goldencode.p2j.util.BlockManager.*;
    import static com.goldencode.p2j.report.ReportConstants.*;
    import static com.goldencode.p2j.util.InternalEntry.Type;

    import java.util.Arrays;
    import java.util.concurrent.atomic.AtomicReference;

    import javax.servlet.http.*;

    /**
     * Business logic (converted to Java from the 4GL source code
     * in OpenEdge/Web/WebResponseWriter.cls).
     */
    @LegacyResource(resource = "OpenEdge.Web.WebResponseWriter")
    @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_PARTIAL)
    public class WebResponseWriter
    extends com.goldencode.p2j.oo.io.OutputStream
    {
       private object<? extends com.goldencode.p2j.oo.net.http.IhttpResponse> response = TypeFactory.object(com.goldencode.p2j.oo.net.http.IhttpResponse.class);

       private handle webStream = TypeFactory.handle();

       private boolean isOpen;
       private boolean preambleWriten;
       private boolean bodyWriten;

       private HttpServletResponse httpResponse;

       @LegacySignature(type = Type.EXECUTE)
       public void __web_WebResponseWriter_execute__()
       {
          onBlockLevel(Condition.ERROR, Action.THROW);
       }

       @LegacySignature(returns = "OBJECT", qualified = "OpenEdge.Net.HTTP.IHttpMessage", type = Type.GETTER, name = "Message")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public object<? extends com.goldencode.p2j.oo.net.http.IhttpMessage> getMessage()
       {
          return function(this, "Message", object.class, new Block((Body) () ->
          {
             returnNormal(response);
          }));
       }

       @LegacySignature(returns = "OBJECT", qualified = "OpenEdge.Net.HTTP.IHttpResponse", type = Type.GETTER, name = "Response")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public object<? extends com.goldencode.p2j.oo.net.http.IhttpResponse> getResponse()
       {
          return function(this, "Response", object.class, new Block((Body) () ->
          {
             returnNormal(response);
          }));
       }

       @LegacySignature(type = Type.SETTER, name = "Response", parameters = {
                @LegacyParameter(qualified = "OpenEdge.Net.HTTP.IHttpResponse", name = "var", type = "OBJECT", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       protected void setResponse(
                final object<? extends com.goldencode.p2j.oo.net.http.IhttpResponse> _var)
       {
          object<? extends com.goldencode.p2j.oo.net.http.IhttpResponse> var = TypeFactory
                   .initInput(_var);

          internalProcedure(WebResponseWriter.class, this, "Response", new Block((Body) () -> {
             Assert.notNull(var, new character("Http Response"));

             response.assign(var);
             open();
          }));
       }

       @LegacySignature(returns = "HANDLE", type = Type.GETTER, name = "WebStream")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_STUB)
       public handle getWebStream()
       {
          return function(this, "WebStream", handle.class, new Block((Body) () ->
          {
             returnNormal(webStream);
          }));
       }

       @LegacySignature(type = Type.CONSTRUCTOR)
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public void __web_WebResponseWriter_constructor__()
       {
          internalProcedure(this, "__web_WebResponseWriter_constructor__", new Block((Body) () ->
          {
             __io_OutputStream_constructor__();
          }));
       }

       @LegacySignature(type = Type.CONSTRUCTOR, parameters =
       {
          @LegacyParameter(name = "p1", type = "OBJECT", qualified = "openedge.net.http.ihttpresponse", mode = "INPUT")
       })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public void __web_WebResponseWriter_constructor__(final object<? extends com.goldencode.p2j.oo.net.http.IhttpResponse> _p1)
       {
          object<? extends com.goldencode.p2j.oo.net.http.IhttpResponse> p1 = TypeFactory
                   .initInput(_p1);

          internalProcedure(this, "__web_WebResponseWriter_constructor__", new Block((Body) () ->
          {
             __web_WebResponseWriter_constructor__();
             setResponse(p1);
          }));
       }

       @LegacySignature(type = Type.METHOD, name = "Close")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public void close()
       {
          internalProcedure(this, "Close", new Block((Body) () ->
          {
             flush();
             // TODO: close the webStream
             httpResponse = null;
             isOpen = false;
          }));
       }

       @LegacySignature(type = Type.METHOD, name = "Flush")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public void flush()
       {
          internalProcedure(this, "Flush", new Block((Body) () ->
          {
             writeHttpPreamble();
             writeBody();

             try
             {
                httpResponse.getOutputStream().flush();
             }
             catch (Exception e)
             {
             }
          }));
       }

       @LegacySignature(type = Type.METHOD, name = "Open")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public void open()
       {
          internalProcedure(this, "Open", new Block((Body) () ->
          {
             // TODO: set the webStream handle
             httpResponse = WebHandler.getHttpResponse();
             preambleWriten = false;
             bodyWriten = false;
             isOpen = true;
          }));
       }

       @LegacySignature(returns = "INT64", type = Type.METHOD, name = "Write", parameters =
       {
          @LegacyParameter(name = "p1", type = "CHARACTER", mode = "INPUT")
       })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public int64 write(final character _p1)
       {
          character p1 = TypeFactory.initInput(_p1);

          return function(this, "Write", int64.class, new Block((Body) () ->
          {
             bodyWriten = true;
             flush();

             if (isWebStreamSet()) {
                try
                {
                   httpResponse.getOutputStream().print(p1.toStringMessage());
                }
                catch (Exception e)
                {
                   // TODO error handling
                }
             }

             returnNormal(TextOps.length(p1));
          }));
       }

       @LegacySignature(returns = "INT64", type = Type.METHOD, name = "Write", parameters =
       {
          @LegacyParameter(name = "p1", type = "LONGCHAR", mode = "INPUT")
       })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public int64 write(final longchar _p1)
       {
          longchar p1 = TypeFactory.initInput(_p1);

          return function(this, "Write", int64.class, new Block((Body) () ->
          {
             bodyWriten = true;
             flush();

             if (isWebStreamSet()) {
                try
                {
                   httpResponse.getOutputStream().print(p1.toStringMessage());
                }
                catch (Exception e)
                {
                   // TODO error handling
                }
             }

             returnNormal(TextOps.length(p1));
          }));
       }

       @LegacySignature(returns = "INT64", type = Type.METHOD, name = "Write", parameters =
       {
          @LegacyParameter(name = "data", type = "MEMPTR", mode = "INPUT"),
          @LegacyParameter(name = "offset", type = "INT64", mode = "INPUT"),
          @LegacyParameter(name = "len", type = "INT64", mode = "INPUT")
       })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       public int64 write(final memptr _data, final int64 _offset, final int64 _len)
       {
          memptr data = TypeFactory.initInput(_data);
          int64 offset = TypeFactory.initInput(_offset);
          int64 len = TypeFactory.initInput(_len);

          return function(this, "Write", int64.class, new Block((Body) () ->
          {
             bodyWriten = true;
             flush();

             int dataLen = data.length().intValue();
             int from = !offset.isUnknown() && offset.intValue() > 0 ? offset.intValue() - 1: -1;
             int to = from >= 0 && !len.isUnknown() && len.intValue() > 0 ? from + len.intValue() : 0;

             if (dataLen > 0 && from >= 0
                      && to > 0
                      && to <= dataLen) {

                if (isWebStreamSet()) {
                   byte[] bytes = data.getByteArray();
                   try
                   {
                      if (from > 0 || to != dataLen)
                      {
                         httpResponse.getOutputStream().write(Arrays.copyOfRange(bytes, from, to));
                      }
                      else
                      {
                         httpResponse.getOutputStream().write(bytes);
                      }
                   } catch (Exception ex)
                   {
                      // TODO: error handling
                      returnNormal(0);
                   }
                }

                returnNormal(len);
             }

             returnNormal(0);
          }));
       }

       @LegacySignature(type = Type.METHOD, name = "WriteBody")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected void writeBody()
       {
          object<? extends MessageWriter> writer = TypeFactory.object(MessageWriter.class);

          internalProcedure(this, "WriteBody", new Block((Body) () -> {
             if (!bodyWriten && response._isValid() && response.ref().getEntity()._isValid())
             {
                bodyWriten = true;

                writer.assign(BodyWriterBuilder.build_1(response).ref().getWriter());

                if (writer._isValid())
                {
                   writer.ref().open();
                   writer.ref().write(response.ref().getEntity());
                   writer.ref().close();

                   memptr data = ObjectOps.cast(writer.ref().getEntity(), ByteBucket.class).ref()
                            .getBytes().ref().getValue();

                   try {
                      // try to set content-length header before preamble
                      response.ref().setContentLength(new integer(data.length()));
                      writeHttpPreamble();

                      write(data, new int64(1), data.length());
                   } finally {
                      data.setLength(0);
                   }

                }
             }
          }));
       }

       @LegacySignature(type = Type.METHOD, name = "WriteCookies")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected void writeCookies()
       {
          object[][] cookies = { TypeFactory.objectExtent(Cookie.class, false) };
          internalProcedure(this, "WriteCookies", new Block((Body) () -> {
             if (response._isValid() && isWebStreamSet())
             {
                int nh = response.ref()
                         .getCookies(new OutputExtentParameter<object<? extends Cookie>>()
                         {
                            @Override
                            public object<? extends Cookie>[] getVariable()
                            {
                               return cookies[0];
                            }

                            @Override
                            public void setVariable(object<? extends Cookie>[] reference)
                            {
                               cookies[0] = reference;
                            }
                         }).intValue();

                for (int i = 0; i < nh; i++)
                {
                   object<? extends Cookie> cookie = cookies[0][i];
                   javax.servlet.http.Cookie httpCookie = new javax.servlet.http.Cookie(
                            cookie.ref().getName().getValue(), cookie.ref().getValue().getValue());

                   httpCookie.setDomain(cookie.ref().getDomain().getValue());
                   httpCookie.setPath(cookie.ref().getPath().getValue());

                   if (!cookie.ref().getMaxAge().isUnknown())
                      httpCookie.setMaxAge(cookie.ref().getMaxAge().intValue());

                   if (cookie.ref().getSecure().booleanValue())
                      httpCookie.setSecure(true);
                   if (cookie.ref().getHttpOnly().booleanValue())
                      httpCookie.setHttpOnly(true);

                   httpResponse.addCookie(httpCookie);
                }
             }
          }));
       }

       @LegacySignature(type = Type.METHOD, name = "WriteHeaders")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       protected void writeHeaders()
       {
          FinalParameterContainer<object<? extends HttpHeader>[]> headers =
                new FinalParameterContainer<>(TypeFactory.objectExtent(HttpHeader.class, false));

          internalProcedure(this, "WriteHeaders", new Block((Body) () ->
          {
             if (response._isValid() && isWebStreamSet()) {

                int nh = response.ref().getHeaders(
                   new OutputExtentParameter<object<? extends HttpHeader>>()
                   {
                      @Override
                      public object<? extends HttpHeader>[] getVariable()
                      {
                         return headers.getValue();
                      }

                      @Override
                      public void setVariable(object<? extends HttpHeader>[] reference)
                      {
                         headers.setValue(reference);
                      }
                   }).intValue();

                for (int i = 0; i < nh; i++)
                {
                   if (i < headers.getValue().length)
                   {
                      writeHeader(headers.getValue()[i]);
                   }
                   else
                   {
                      System.out.println("Missing header! " + i + " >= " + headers.getValue().length + "!");
                   }
                }
             }
          }));
       }

       private void writeHeader(object<? extends HttpHeader> hdr)
       {
          if (hdr.ref() == null)
          {
             System.out.println("Something went very bad: the header object was DELETED before being used.");
             return;
          }

          if (isWebStreamSet())
          {
             httpResponse.setHeader(hdr.ref().getName().getValue(),
                                    hdr.ref().getBaseValue().getValue() + hdr.ref().getParameterValues().getValue());
          }
       }

       @LegacySignature(type = Type.METHOD, name = "WriteHttpPreamble")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       protected void writeHttpPreamble()
       {
          internalProcedure(this, "WriteHttpPreamble", new Block((Body) () ->
          {
             if (preambleWriten)
                return;

             preambleWriten = true;

             if (!CompareOps._isEqual(response.ref().getTransferEncoding(), character.valueOf(TransferEncodingEnum.none)))
                writeHeader(HttpHeaderBuilder.build(new character("Transfer-Encoding")).ref().value(response.ref().getTransferEncoding()).ref().getHeader());

             writeStatusLine();

             // this should cover content-type, character encoding as well
             writeHeaders();
             writeCookies();

          }));
       }

       @SuppressWarnings("deprecation")
       @LegacySignature(type = Type.METHOD, name = "WriteStatusLine")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL|RT_LVL_FULL)
       protected void writeStatusLine()
       {
          internalProcedure(this, "WriteStatusLine", new Block((Body) () ->
          {
             if (response._isValid() && isWebStreamSet())
             {
                if (response.ref().getStatusReason().isUnknown())
                {
                   httpResponse.setStatus(response.ref().getStatusCode().intValue());
                }
                else
                {
                   httpResponse.setStatus(response.ref().getStatusCode().intValue(),
                            response.ref().getStatusReason().toStringMessage());
                }
             }
          }));
       }

       private boolean isWebStreamSet () {
          // in 4GL trying to write to a closed stream raise error,
          // however the "WEB" stream can be open in a non web environment and no error is thrown
          if (!isOpen) {
             ErrorManager.recordOrThrowError(1387, "Attempt to write to closed stream WebStream.", true, true);
          }

          return httpResponse != null;
       }

    }