# LegacyIterator.java

    /*
    ** Module   : LegacyIterator.java
    ** Abstract : Implementation of the builtin class.
    **
    ** Copyright (c) 2019-2023, Golden Code Development Corporation.
    **
    ** -#- -I- --Date-- ---------------------------------------Description----------------------------------------
    ** 001 ME  20200514 First version, stubs taken by converting the skeleton using FWD.
    ** 002 ME  20201016 Change it to work with the collection image at the time of instantiation.
    **                  No protection against collection modification initial image is needed,
    **                  accommodate other 4GL oddities.
    ** 003 CA  20210113 Renamed Iiterator.next to Iiterator.next_, to follow NameConverter's rules.
    ** 004 CA  20210221 Fixed 'qualified', 'extent' and 'returns' annotations at the legacy
    **                  signature.
    **     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.
    ** 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.core.collections;

    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.collections.Iiterator;
    import com.goldencode.p2j.oo.lang.*;
    import com.goldencode.p2j.persist.P2JQuery;
    import com.goldencode.p2j.persist.QueryWrapper;
    import com.goldencode.p2j.persist.RecordBuffer;

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

    import java.util.ArrayList;
    import java.util.Collection;
    import java.util.Iterator;

    /**
     * Business logic (converted to Java from the 4GL source code
     * in OpenEdge/Core/Collections/Iterator.cls).
     */
    @LegacyResource(resource = "OpenEdge.Core.Collections.Iterator")
    @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
    public class LegacyIterator extends BaseObject implements Iiterator
    {
       @LegacySignature(type = Type.PROPERTY, name = "OwnerCollection")
       private object<? extends Icollection> ownerCollection = TypeFactory.object(Icollection.class);

       @LegacySignature(type = Type.PROPERTY, name = "QueryHandle")
       private handle queryHandle = TypeFactory.handle();

       @LegacySignature(type = Type.PROPERTY, name = "BufferHandle")
       private handle bufferHandle = TypeFactory.handle();

       @LegacySignature(type = Type.PROPERTY, name = "ObjectFieldHandle")
       private handle objectFieldHandle = TypeFactory.handle();

       private Collection objectsCollection;
       private boolean emptyCollection;

       private Iterator<object<? extends _BaseObject_>> iterator;
       private object<? extends _BaseObject_> next;

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

       @LegacySignature(returns = "OBJECT", qualified = "OpenEdge.Core.Collections.ICollection", type = Type.GETTER, name = "OwnerCollection")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected object<? extends Icollection> getOwnerCollection()
       {
          return function(LegacyIterator.class, this, "OwnerCollection", object.class,
                   new Block((Body) () ->
                   {
                      returnNormal(ownerCollection);
                   }));
       }

       @LegacySignature(type = Type.SETTER, name = "OwnerCollection", parameters = {
                @LegacyParameter(qualified = "OpenEdge.Core.Collections.ICollection", name = "var", type = "OBJECT", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected void setOwnerCollection(final object<? extends Icollection> _var)
       {
          object<? extends Icollection> var = TypeFactory.initInput(_var);

          internalProcedure(LegacyIterator.class, this, "OwnerCollection", new Block((Body) () ->
          {
             ownerCollection.assign(var);
          }));
       }

       @LegacySignature(returns = "HANDLE", type = Type.GETTER, name = "QueryHandle")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected handle getQueryHandle()
       {
          return function(LegacyIterator.class, this, "QueryHandle", handle.class,
                   new Block((Body) () ->
                   {
                      returnNormal(queryHandle);
                   }));
       }

       @LegacySignature(type = Type.SETTER, name = "QueryHandle", parameters = {
                @LegacyParameter(name = "var", type = "HANDLE", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected void setQueryHandle(final handle _var)
       {
          handle var = TypeFactory.initInput(_var);

          internalProcedure(LegacyIterator.class, this, "QueryHandle", new Block((Body) () ->
          {
             queryHandle.assign(var);
          }));
       }

       @LegacySignature(returns = "HANDLE", type = Type.GETTER, name = "BufferHandle")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected handle getBufferHandle()
       {
          return function(LegacyIterator.class, this, "BufferHandle", handle.class,
                   new Block((Body) () ->
                   {
                      returnNormal(bufferHandle);
                   }));
       }

       @LegacySignature(type = Type.SETTER, name = "BufferHandle", parameters = {
                @LegacyParameter(name = "var", type = "HANDLE", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected void setBufferHandle(final handle _var)
       {
          handle var = TypeFactory.initInput(_var);

          internalProcedure(LegacyIterator.class, this, "BufferHandle", new Block((Body) () ->
          {
             bufferHandle.assign(var);
          }));
       }

       @LegacySignature(returns = "HANDLE", type = Type.GETTER, name = "ObjectFieldHandle")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected handle getObjectFieldHandle()
       {
          return function(LegacyIterator.class, this, "ObjectFieldHandle", handle.class,
                   new Block((Body) () ->
                   {
                      returnNormal(objectFieldHandle);
                   }));
       }

       @LegacySignature(type = Type.SETTER, name = "ObjectFieldHandle", parameters = {
                @LegacyParameter(name = "var", type = "HANDLE", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       protected void setObjectFieldHandle(final handle _var)
       {
          handle var = TypeFactory.initInput(_var);

          internalProcedure(LegacyIterator.class, this, "ObjectFieldHandle", new Block((Body) () ->
          {
             objectFieldHandle.assign(var);
          }));
       }

       @LegacySignature(type = Type.CONSTRUCTOR, parameters = {
                @LegacyParameter(name = "p1", type = "OBJECT", qualified = "openedge.core.collections.icollection", mode = "INPUT"),
                @LegacyParameter(name = "p2", type = "HANDLE", mode = "INPUT"),
                @LegacyParameter(name = "p3", type = "CHARACTER", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public void __core_collections_LegacyIterator_constructor__(
                final object<? extends Icollection> _p1, final handle _p2, final character _p3)
       {
          internalProcedure(LegacyIterator.class, this,
                   "__core_collections_LegacyIterator_constructor__", new Block((Body) () ->
                   {
                      __core_collections_LegacyIterator_constructor__(_p1, _p2, _p3,
                               new character(""), new character(""));
                   }));
       }

       @LegacySignature(type = Type.CONSTRUCTOR, parameters = {
                @LegacyParameter(name = "p1", type = "OBJECT", qualified = "openedge.core.collections.icollection", mode = "INPUT"),
                @LegacyParameter(name = "p2", type = "HANDLE", mode = "INPUT"),
                @LegacyParameter(name = "p3", type = "CHARACTER", mode = "INPUT"),
                @LegacyParameter(name = "p4", type = "CHARACTER", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public void __core_collections_LegacyIterator_constructor__(
                final object<? extends Icollection> _p1, final handle _p2, final character _p3,
                final character _p4)
       {
          internalProcedure(LegacyIterator.class, this,
                   "__core_collections_LegacyIterator_constructor__", new Block((Body) () ->
                   {
                      __core_collections_LegacyIterator_constructor__(_p1, _p2, _p3, _p4,
                               new character(""));
                   }));
       }

       @LegacySignature(type = Type.CONSTRUCTOR, parameters = {
                @LegacyParameter(name = "p1", type = "OBJECT", qualified = "openedge.core.collections.icollection", mode = "INPUT"),
                @LegacyParameter(name = "p2", type = "HANDLE", mode = "INPUT"),
                @LegacyParameter(name = "p3", type = "CHARACTER", mode = "INPUT"),
                @LegacyParameter(name = "p4", type = "CHARACTER", mode = "INPUT"),
                @LegacyParameter(name = "p5", type = "CHARACTER", mode = "INPUT") })
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public void __core_collections_LegacyIterator_constructor__(
                final object<? extends Icollection> _p1, final handle _p2, final character _p3,
                final character _p4, final character _p5)
       {
          object<? extends Icollection> oCol = TypeFactory.initInput(_p1);
          handle phTT = TypeFactory.initInput(_p2);
          character valField = TypeFactory.initInput(_p3);
          character sortField = TypeFactory.initInput(_p4);
          character whereString = TypeFactory.initInput(_p5);

          internalProcedure(LegacyIterator.class, this,
                   "__core_collections_LegacyIterator_constructor__", new Block((Body) () ->
                   {
                      __lang_BaseObject_constructor__();
                      ownerCollection.assign(oCol);

                      // default 4GL temp-table implementation
                      if (phTT.isType(LegacyResource.TEMP_TABLE) || phTT.isType(LegacyResource.BUFFER))
                      {
                         RecordBuffer.create(bufferHandle, phTT);

                         objectFieldHandle.assign(bufferHandle.unwrapBuffer().bufferField(valField));
                         QueryWrapper.createQuery(queryHandle);
                         queryHandle.unwrapBufferCollection().setBuffers(bufferHandle);
                         StringBuffer qryString = new StringBuffer();

                         if (!TextOps.isEmpty(whereString.getValue()))
                            qryString.append(" where " + whereString.getValue());

                         if (!TextOps.isEmpty(sortField.getValue()))
                            qryString.append(" by " + sortField.getValue());
                         else
                            queryHandle.unwrapQuery().changeForwardOnly(true);
                         queryHandle.unwrapQuery()
                                  .prepare(String.format("preselect each %s %s no-lock",
                                           bufferHandle.unwrap().name().getValue(), qryString.toString()));

                         queryHandle.unwrapQuery().queryOpen();
                         iterator = null;
                      }
                      else
                      {
                         Object resource = phTT.get();
                         if (resource instanceof Collection) {
                            // keep a reference to the actual objects collections
                            objectsCollection = (Collection) resource;
                            emptyCollection = objectsCollection.isEmpty();
                            // make a copy so the iterator always sees the elements present when created
                            iterator = new ArrayList(objectsCollection).iterator();
                         }
                      }
                   }));
       }

       @LegacySignature(returns = "LOGICAL", type = Type.METHOD, name = "HasNext")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public logical hasNext()
       {
          return function(LegacyIterator.class, this, "HasNext", logical.class, new Block((Body) () ->
          {
             if (iterator != null)
             {
                // 4GL BUG, if collection (temp-table) was empty hasNext returns unknown
                returnNormal(emptyCollection ? new logical() : new logical(iterator.hasNext()));
             }
             else
             {
                P2JQuery qry = queryHandle.unwrapQuery();

                if (qry._isOffEnd())
                {
                   boolean ok = qry.forward(1);
                   if (!qry.forwardOnly().booleanValue())
                      qry.backward(1);
                   returnNormal(ok);
                }
                else if (qry.getNumResults().intValue() == 1 && qry.currentRow().intValue() == 1)
                {
                   returnNormal(!bufferHandle.unwrapBuffer().available().booleanValue());
                }
                else
                {
                   returnNormal(qry.currentRow().intValue() < qry.getNumResults().intValue());
                }
             }
          }));
       }

       @LegacySignature(returns = "OBJECT", type = Type.METHOD, name = "Next", qualified = "progress.lang.object")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public object<? extends com.goldencode.p2j.oo.lang._BaseObject_> next_()
       {
          object<_BaseObject_> ret = TypeFactory.object(_BaseObject_.class);

          return function(LegacyIterator.class, this, "Next", object.class, new Block((Body) () ->
          {
             if (iterator != null)
             {
                while (iterator.hasNext()) {
                   next = iterator.next();

                   // check if object still in original collection, if removed skip
                   if (objectsCollection.contains(next))
                   {
                      returnNormal(next);
                   }
                   else
                   {
                      next = null;
                   }
                }

                returnNormal(new object());
             }
             else
             {
                queryHandle.unwrapQuery().next();

                if (bufferHandle.unwrapBuffer()._available())
                {
                   ret.assign(objectFieldHandle.unwrapBufferField().value());
                }

                returnNormal(ret);
             }
          }));
       }

       @LegacySignature(returns = "LOGICAL", type = Type.METHOD, name = "Remove")
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public logical remove()
       {
          return function(LegacyIterator.class, this, "Remove", logical.class, new Block((Body) () ->
          {
             if (iterator != null)
             {
                if (next == null)
                {
                   returnNormal(false);
                }
                else
                {
                   iterator.remove();
                   // remove the item from parent collection, iterator is working on a copy
                   if (ownerCollection._isValid())
                      ownerCollection.ref().remove(next);
                   next = null;

                   returnNormal(true);
                }
             }
             else
             {
                boolean ok = false;
                if (bufferHandle.unwrapBuffer()._available())
                {
                   ok = ownerCollection.ref()
                            .remove((object<? extends _BaseObject_>) objectFieldHandle
                                     .unwrapBufferField().value())
                            .booleanValue();
                   if (ok)
                   {
                      queryHandle.unwrapQuery().deleteResultListEntry();
                   }
                }

                returnNormal(ok);
             }
          }));
       }

       @LegacySignature(type = Type.DESTRUCTOR)
       @LegacyResourceSupport(supportLvl = CVT_LVL_FULL | RT_LVL_FULL)
       public void __core_collections_LegacyIterator_destructor__()
       {
          internalProcedure(LegacyIterator.class, this,
                   "__core_collections_LegacyIterator_destructor__", new Block((Body) () ->
                   {
                      if (bufferHandle._isValid())
                         HandleOps.delete(bufferHandle);
                      if (queryHandle._isValid())
                         HandleOps.delete(queryHandle);
                   }));
       }
    }