//-----------------------------------------------------------------------------
// Copyright (c) 2013 GarageGames, LLC
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//-----------------------------------------------------------------------------

#include "consoleNamespace.h"

#include "platform/platform.h"
#include "console/console.h"

#include "console/ast.h"
#include "collection/findIterator.h"
#include "io/resource/resourceManager.h"

#include "string/findMatch.h"
#include "console/consoleInternal.h"
#include "io/fileStream.h"
#include "console/compiler.h"

#include "consoleNamespace_ScriptBinding.h"

U32 Namespace::mCacheSequence = 0;
DataChunker Namespace::mCacheAllocator;
DataChunker Namespace::mAllocator;
Namespace *Namespace::mNamespaceList = NULL;
Namespace *Namespace::mGlobalNamespace = NULL;



Namespace::Entry::Entry()
{
   mCode = NULL;
   mType = InvalidFunctionType;
}

void Namespace::Entry::clear()
{
   if(mCode)
   {
      mCode->decRefCount();
      mCode = NULL;
   }

   // Clean up usage strings generated for script functions.
   if( ( mType == Namespace::Entry::ScriptFunctionType ) && mUsage )
   {
      delete mUsage;
      mUsage = NULL;
   }
}

Namespace::Namespace()
{
   mPackage = NULL;
   mUsage = NULL;
   mCleanUpUsage = false;
   mName = NULL;
   mParent = NULL;
   mNext = NULL;
   mEntryList = NULL;
   mHashSize = 0;
   mHashTable = 0;
   mHashSequence = 0;
   mRefCountToParent = 0;
   mClassRep = 0;
}

Namespace::~Namespace()
{
   if( mUsage && mCleanUpUsage )
   {
      dFree (const_cast <char *> (mUsage));
      mUsage = NULL;
      mCleanUpUsage = false;
   }
}

void Namespace::clearEntries()
{
   for(Entry *walk = mEntryList; walk; walk = walk->mNext)
      walk->clear();
}

Namespace *Namespace::find(StringTableEntry name, StringTableEntry package)
{
   for(Namespace *walk = mNamespaceList; walk; walk = walk->mNext)
      if(walk->mName == name && walk->mPackage == package)
         return walk;

   Namespace *ret = (Namespace *) mAllocator.alloc(sizeof(Namespace));
   constructInPlace(ret);
   ret->mPackage = package;
   ret->mName = name;
   ret->mNext = mNamespaceList;
   mNamespaceList = ret;
   return ret;
}

bool Namespace::canTabComplete(const char *prevText, const char *bestMatch, const char *newText, S32 baseLen, bool fForward)
{
   // test if it matches the first baseLen chars:
   if(dStrnicmp(newText, prevText, baseLen))
      return false;

   if (fForward)
   {
      if(!bestMatch)
         return dStricmp(newText, prevText) > 0;
      else
         return (dStricmp(newText, prevText) > 0) &&
                (dStricmp(newText, bestMatch) < 0);
   }
   else
   {
      if (dStrlen(prevText) == (U32) baseLen)
      {
         // look for the 'worst match'
         if(!bestMatch)
            return dStricmp(newText, prevText) > 0;
         else
            return dStricmp(newText, bestMatch) > 0;
      }
      else
      {
         if (!bestMatch)
            return (dStricmp(newText, prevText)  < 0);
         else
            return (dStricmp(newText, prevText)  < 0) &&
                   (dStricmp(newText, bestMatch) > 0);
      }
   }
}

bool Namespace::unlinkClass(Namespace* parent)
{
   Namespace* walk = this;

   while(walk->mParent && walk->mParent->mName == mName)
      walk = walk->mParent;

   // Make sure "parent" is the direct parent namespace.
   if(walk->mParent && walk->mParent != parent)
   {
      Con::errorf(ConsoleLogEntry::General, "Namespace::unlinkClass - cannot unlink namespace parent linkage for %s for %s.",
         walk->mName, walk->mParent->mName);
      return false;
   }

   // Decrease the reference count. Note that we do this on the bottom-most namespace.
   AssertWarn(mRefCountToParent > 0, "Namespace::unlinkClass - reference count to parent is already at 0");
   mRefCountToParent--;

   // Unlink if the count dropped to zero.
   if(mRefCountToParent == 0)
   {
      walk->mParent = NULL;
      trashCache();
   }

   return true;
}


bool Namespace::classLinkTo(Namespace* parent)
{
   Namespace* walk = this;

   while(walk->mParent && walk->mParent->mName == mName)
      walk = walk->mParent;

   // Make sure there is no existing parent namespace.
   if(walk->mParent && walk->mParent != parent)
   {
      Con::errorf(ConsoleLogEntry::General, "Namespace::classLinkTo - cannot change namespace parent linkage of %s from %s to %s.",
         walk->mName, walk->mParent->mName, parent->mName);
      return false;
   }

   // Increase the reference count and add the parent namespace.
   mRefCountToParent++;
   walk->mParent = parent;

   trashCache();

   return true;
}

void Namespace::buildHashTable()
{
   if(mHashSequence == mCacheSequence)
      return;

   if(!mEntryList && mParent)
   {
      mParent->buildHashTable();
      mHashTable = mParent->mHashTable;
      mHashSize = mParent->mHashSize;
      mHashSequence = mCacheSequence;
      return;
   }

   U32 entryCount = 0;
   Namespace * ns;
   for(ns = this; ns; ns = ns->mParent)
      for(Entry *walk = ns->mEntryList; walk; walk = walk->mNext)
         if(lookupRecursive(walk->mFunctionName) == walk)
            entryCount++;

   mHashSize = entryCount + (entryCount >> 1) + 1;

   if(!(mHashSize & 1))
      mHashSize++;

   mHashTable = (Entry **) mCacheAllocator.alloc(sizeof(Entry *) * mHashSize);
   for(U32 i = 0; i < mHashSize; i++)
      mHashTable[i] = NULL;

   for(ns = this; ns; ns = ns->mParent)
   {
      for(Entry *walk = ns->mEntryList; walk; walk = walk->mNext)
      {
         U32 index = HashPointer(walk->mFunctionName) % mHashSize;
         while(mHashTable[index] && mHashTable[index]->mFunctionName != walk->mFunctionName)
         {
            index++;
            if(index >= mHashSize)
               index = 0;
         }

         if(!mHashTable[index])
            mHashTable[index] = walk;
      }
   }

   mHashSequence = mCacheSequence;
}

void Namespace::init()
{
   // create the global namespace
   mGlobalNamespace = find(NULL);
}

Namespace *Namespace::global()
{
   return mGlobalNamespace;
}

void Namespace::shutdown()
{
   for(Namespace *walk = mNamespaceList; walk; walk = walk->mNext)
      walk->clearEntries();
}

void Namespace::trashCache()
{
   mCacheSequence++;
   mCacheAllocator.freeBlocks();
}

const char *Namespace::tabComplete(const char *prevText, S32 baseLen, bool fForward)
{
   if(mHashSequence != mCacheSequence)
      buildHashTable();

   const char *bestMatch = NULL;
   for(U32 i = 0; i < mHashSize; i++)
      if(mHashTable[i] && canTabComplete(prevText, bestMatch, mHashTable[i]->mFunctionName, baseLen, fForward))
         bestMatch = mHashTable[i]->mFunctionName;
   return bestMatch;
}

Namespace::Entry *Namespace::lookupRecursive(StringTableEntry name)
{
   for(Namespace *ns = this; ns; ns = ns->mParent)
      for(Entry *walk = ns->mEntryList; walk; walk = walk->mNext)
         if(walk->mFunctionName == name)
            return walk;

   return NULL;
}

Namespace::Entry *Namespace::lookup(StringTableEntry name)
{
   if(mHashSequence != mCacheSequence)
      buildHashTable();

   U32 index = HashPointer(name) % mHashSize;
   while(mHashTable[index] && mHashTable[index]->mFunctionName != name)
   {
      index++;
      if(index >= mHashSize)
         index = 0;
   }
   return mHashTable[index];
}

static S32 QSORT_CALLBACK compareEntries(const void* a,const void* b)
{
   const Namespace::Entry* fa = *((Namespace::Entry**)a);
   const Namespace::Entry* fb = *((Namespace::Entry**)b);

   return dStricmp(fa->mFunctionName, fb->mFunctionName);
}

void Namespace::getEntryList(Vector<Entry *> *vec)
{
   if(mHashSequence != mCacheSequence)
      buildHashTable();

   for(U32 i = 0; i < mHashSize; i++)
      if(mHashTable[i])
         vec->push_back(mHashTable[i]);

   dQsort(vec->address(),vec->size(),sizeof(Namespace::Entry *),compareEntries);
}

Namespace::Entry *Namespace::createLocalEntry(StringTableEntry name)
{
   for(Entry *walk = mEntryList; walk; walk = walk->mNext)
   {
      if(walk->mFunctionName == name)
      {
         walk->clear();
         return walk;
      }
   }

   Entry *ent = (Entry *) mAllocator.alloc(sizeof(Entry));
   constructInPlace(ent);

   ent->mNamespace = this;
   ent->mFunctionName = name;
   ent->mNext = mEntryList;
   ent->mPackage = mPackage;
   mEntryList = ent;
   return ent;
}

void Namespace::addFunction(StringTableEntry name, CodeBlock *cb, U32 functionOffset, const char* usage)
{
   Entry *ent = createLocalEntry(name);
   trashCache();

   ent->mUsage = usage;
   ent->mCode = cb;
   ent->mFunctionOffset = functionOffset;
   ent->mCode->incRefCount();
   ent->mType = Entry::ScriptFunctionType;
}

void Namespace::addCommand(StringTableEntry name,StringCallback cb, const char *usage, S32 minArgs, S32 maxArgs)
{
   Entry *ent = createLocalEntry(name);
   trashCache();

   ent->mUsage = usage;
   ent->mMinArgs = minArgs;
   ent->mMaxArgs = maxArgs;

   ent->mType = Entry::StringCallbackType;
   ent->cb.mStringCallbackFunc = cb;
}

void Namespace::addCommand(StringTableEntry name,IntCallback cb, const char *usage, S32 minArgs, S32 maxArgs)
{
   Entry *ent = createLocalEntry(name);
   trashCache();

   ent->mUsage = usage;
   ent->mMinArgs = minArgs;
   ent->mMaxArgs = maxArgs;

   ent->mType = Entry::IntCallbackType;
   ent->cb.mIntCallbackFunc = cb;
}

void Namespace::addCommand(StringTableEntry name,VoidCallback cb, const char *usage, S32 minArgs, S32 maxArgs)
{
   Entry *ent = createLocalEntry(name);
   trashCache();

   ent->mUsage = usage;
   ent->mMinArgs = minArgs;
   ent->mMaxArgs = maxArgs;

   ent->mType = Entry::VoidCallbackType;
   ent->cb.mVoidCallbackFunc = cb;
}

void Namespace::addCommand(StringTableEntry name,FloatCallback cb, const char *usage, S32 minArgs, S32 maxArgs)
{
   Entry *ent = createLocalEntry(name);
   trashCache();

   ent->mUsage = usage;
   ent->mMinArgs = minArgs;
   ent->mMaxArgs = maxArgs;

   ent->mType = Entry::FloatCallbackType;
   ent->cb.mFloatCallbackFunc = cb;
}

void Namespace::addCommand(StringTableEntry name,BoolCallback cb, const char *usage, S32 minArgs, S32 maxArgs)
{
   Entry *ent = createLocalEntry(name);
   trashCache();

   ent->mUsage = usage;
   ent->mMinArgs = minArgs;
   ent->mMaxArgs = maxArgs;

   ent->mType = Entry::BoolCallbackType;
   ent->cb.mBoolCallbackFunc = cb;
}

void Namespace::addOverload(const char * name, const char *altUsage)
{
   static U32 uid=0;
   char buffer[1024];
   char lilBuffer[32];
   dStrcpy(buffer, name);
   dSprintf(lilBuffer, 32, "_%d", uid++);
   dStrcat(buffer, lilBuffer);

   Entry *ent = createLocalEntry(StringTable->insert( buffer ));
   trashCache();

   ent->mUsage = altUsage;
   ent->mMinArgs = -1;
   ent->mMaxArgs = -2;

   ent->mType = Entry::OverloadMarker;
   ent->cb.mGroupName = name;
}

void Namespace::markGroup(const char* name, const char* usage)
{
   static U32 uid=0;
   char buffer[1024];
   char lilBuffer[32];
   dStrcpy(buffer, name);
   dSprintf(lilBuffer, 32, "_%d", uid++);
   dStrcat(buffer, lilBuffer);

   Entry *ent = createLocalEntry(StringTable->insert( buffer ));
   trashCache();

   if(usage != NULL)
      lastUsage = (char*)(ent->mUsage = usage);
   else
      ent->mUsage = lastUsage;

   ent->mMinArgs = -1; // Make sure it explodes if somehow we run this entry.
   ent->mMaxArgs = -2;

   ent->mType = Entry::GroupMarker;
   ent->cb.mGroupName = name;
}

extern S32 executeBlock(StmtNode *block, ExprEvalState *state);

const char *Namespace::Entry::execute(S32 argc, const char **argv, ExprEvalState *state)
{
   if(mType == ScriptFunctionType)
   {
      if(mFunctionOffset)
         return mCode->exec(mFunctionOffset, argv[0], mNamespace, argc, argv, false, mPackage);
      else
         return "";
   }

   if((mMinArgs && argc < mMinArgs) || (mMaxArgs && argc > mMaxArgs))
   {
      Con::warnf(ConsoleLogEntry::Script, "%s::%s - wrong number of arguments.", mNamespace->mName, mFunctionName);
      Con::warnf(ConsoleLogEntry::Script, "usage: %s", mUsage);
      return "";
   }

   static char returnBuffer[32];
   switch(mType)
   {
      case StringCallbackType:
         return cb.mStringCallbackFunc(state->thisObject, argc, argv);
      case IntCallbackType:
         dSprintf(returnBuffer, sizeof(returnBuffer), "%d",
            cb.mIntCallbackFunc(state->thisObject, argc, argv));
         return returnBuffer;
      case FloatCallbackType:
         dSprintf(returnBuffer, sizeof(returnBuffer), "%.9g",
            cb.mFloatCallbackFunc(state->thisObject, argc, argv));
         return returnBuffer;
      case VoidCallbackType:
         cb.mVoidCallbackFunc(state->thisObject, argc, argv);
         return "";
      case BoolCallbackType:
         dSprintf(returnBuffer, sizeof(returnBuffer), "%d",
            (U32)cb.mBoolCallbackFunc(state->thisObject, argc, argv));
         return returnBuffer;
   }

   return "";
}

StringTableEntry Namespace::mActivePackages[Namespace::MaxActivePackages];
U32 Namespace::mNumActivePackages = 0;
U32 Namespace::mOldNumActivePackages = 0;

bool Namespace::isPackage(StringTableEntry name)
{
   for(Namespace *walk = mNamespaceList; walk; walk = walk->mNext)
      if(walk->mPackage == name)
         return true;
   return false;
}

void Namespace::activatePackage(StringTableEntry name)
{
   if(mNumActivePackages == MaxActivePackages)
   {
      Con::printf("ActivatePackage(%s) failed - Max package limit reached: %d", name, MaxActivePackages);
      return;
   }
   if(!name)
      return;

   // see if this one's already active
   for(U32 i = 0; i < mNumActivePackages; i++)
      if(mActivePackages[i] == name)
         return;

   // kill the cache
   trashCache();

   // find all the package namespaces...
   for(Namespace *walk = mNamespaceList; walk; walk = walk->mNext)
   {
      if(walk->mPackage == name)
      {
         Namespace *parent = Namespace::find(walk->mName);
         // hook the parent
         walk->mParent = parent->mParent;
         parent->mParent = walk;

         // now swap the entries:
         Entry *ew;
         for(ew = parent->mEntryList; ew; ew = ew->mNext)
            ew->mNamespace = walk;

         for(ew = walk->mEntryList; ew; ew = ew->mNext)
            ew->mNamespace = parent;

         ew = walk->mEntryList;
         walk->mEntryList = parent->mEntryList;
         parent->mEntryList = ew;
      }
   }
   mActivePackages[mNumActivePackages++] = name;
}

void Namespace::deactivatePackage(StringTableEntry name)
{
   S32 i, j;
   for(i = 0; i < (S32)mNumActivePackages; i++)
      if(mActivePackages[i] == name)
         break;
   if(i == mNumActivePackages)
      return;

   trashCache();

   for(j = mNumActivePackages - 1; j >= i; j--)
   {
      // gotta unlink em in reverse order...
      for(Namespace *walk = mNamespaceList; walk; walk = walk->mNext)
      {
         if(walk->mPackage == mActivePackages[j])
         {
            Namespace *parent = Namespace::find(walk->mName);
            // hook the parent
            parent->mParent = walk->mParent;
            walk->mParent = NULL;

            // now swap the entries:
            Entry *ew;
            for(ew = parent->mEntryList; ew; ew = ew->mNext)
               ew->mNamespace = walk;

            for(ew = walk->mEntryList; ew; ew = ew->mNext)
               ew->mNamespace = parent;

            ew = walk->mEntryList;
            walk->mEntryList = parent->mEntryList;
            parent->mEntryList = ew;
         }
      }
   }
   mNumActivePackages = i;
}

void Namespace::unlinkPackages()
{
   mOldNumActivePackages = mNumActivePackages;
   if(!mNumActivePackages)
      return;
   deactivatePackage(mActivePackages[0]);
}

void Namespace::relinkPackages()
{
   if(!mOldNumActivePackages)
      return;
   for(U32 i = 0; i < mOldNumActivePackages; i++)
      activatePackage(mActivePackages[i]);
}