//-----------------------------------------------------------------------------
// Copyright (c) 2012 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 "platform/platform.h"
#include "console/console.h"
#include "console/telnetDebugger.h"

#include "console/ast.h"
#include "core/tAlgorithm.h"

#include "core/strings/findMatch.h"
#include "console/consoleInternal.h"
#include "core/stream/fileStream.h"
#include "console/compiler.h"

#include "console/simBase.h"

extern FuncVars gEvalFuncVars;
extern FuncVars gGlobalScopeFuncVars;
extern FuncVars *gFuncVars;

namespace Con
{
extern bool scriptWarningsAsAsserts;
};

namespace Compiler
{

   F64 consoleStringToNumber(const char *str, StringTableEntry file, U32 line)
   {
      F64 val = dAtof(str);
      if (val != 0)
         return val;
      else if (!dStricmp(str, "true"))
         return 1;
      else if (!dStricmp(str, "false"))
         return 0;
      else if (file)
      {
         Con::warnf(ConsoleLogEntry::General, "%s (%d): string always evaluates to 0.", file, line);
         return 0;
      }
      return 0;
   }

   //------------------------------------------------------------

   CompilerStringTable *gCurrentStringTable, gGlobalStringTable, gFunctionStringTable;
   CompilerFloatTable  *gCurrentFloatTable, gGlobalFloatTable, gFunctionFloatTable;
   DataChunker          gConsoleAllocator;
   CompilerIdentTable   gIdentTable;
   CompilerLocalVariableToRegisterMappingTable gFunctionVariableMappingTable;

   //------------------------------------------------------------

   void evalSTEtoCode(StringTableEntry ste, U32 ip, U32 *ptr)
   {
#if defined(TORQUE_CPU_X64) || defined(TORQUE_CPU_ARM64)
      *(U64*)(ptr) = (U64)ste;
#else
      *ptr = (U32)ste;
#endif
   }

   void compileSTEtoCode(StringTableEntry ste, U32 ip, U32 *ptr)
   {
      if (ste)
         getIdentTable().add(ste, ip);
      *ptr = 0;
      *(ptr + 1) = 0;
   }

   void(*STEtoCode)(StringTableEntry ste, U32 ip, U32 *ptr) = evalSTEtoCode;

   //------------------------------------------------------------

   bool gSyntaxError = false;
   bool gIsEvalCompile = false;

   //------------------------------------------------------------

   CompilerStringTable *getCurrentStringTable() { return gCurrentStringTable; }
   CompilerStringTable &getGlobalStringTable() { return gGlobalStringTable; }
   CompilerStringTable &getFunctionStringTable() { return gFunctionStringTable; }

   CompilerLocalVariableToRegisterMappingTable& getFunctionVariableMappingTable() { return gFunctionVariableMappingTable; }

   void setCurrentStringTable(CompilerStringTable* cst) { gCurrentStringTable = cst; }

   CompilerFloatTable *getCurrentFloatTable() { return gCurrentFloatTable; }
   CompilerFloatTable &getGlobalFloatTable() { return gGlobalFloatTable; }
   CompilerFloatTable &getFunctionFloatTable() { return gFunctionFloatTable; }

   void setCurrentFloatTable(CompilerFloatTable* cst) { gCurrentFloatTable = cst; }

   CompilerIdentTable &getIdentTable() { return gIdentTable; }

   void precompileIdent(StringTableEntry ident)
   {
      if (ident)
         gGlobalStringTable.add(ident);
   }

   void resetTables()
   {
      setCurrentStringTable(&gGlobalStringTable);
      setCurrentFloatTable(&gGlobalFloatTable);
      getGlobalFloatTable().reset();
      getGlobalStringTable().reset();
      getFunctionFloatTable().reset();
      getFunctionStringTable().reset();
      getIdentTable().reset();
      getFunctionVariableMappingTable().reset();
      gGlobalScopeFuncVars.clear();
      gFuncVars = gIsEvalCompile ? &gEvalFuncVars : &gGlobalScopeFuncVars;
   }

   void *consoleAlloc(U32 size) { return gConsoleAllocator.alloc(size); }
   void consoleAllocReset() { gConsoleAllocator.freeBlocks(); }

   void scriptErrorHandler(const char* str)
   {
      if (Con::scriptWarningsAsAsserts)
      {
         AssertISV(false, str);
      }
      else
      {
         Con::warnf(ConsoleLogEntry::Type::Script, "%s", str);
      }
   }
}

//-------------------------------------------------------------------------

using namespace Compiler;

S32 FuncVars::assign(StringTableEntry var, TypeReq currentType, S32 lineNumber, bool isConstant)
{
   std::unordered_map<StringTableEntry, Var>::iterator found = vars.find(var);
   if (found != vars.end())
   {
      if (found->second.isConstant)
      {
         const char* str = avar("Script Warning: Reassigning variable %s when it is a constant. File: %s Line : %d", var, CodeBlock::smCurrentParser->getCurrentFile(), lineNumber);
         scriptErrorHandler(str);
      }
      return found->second.reg;
   }

   S32 id = counter++;
   vars[var] = { id, currentType, var, isConstant };
   variableNameMap[id] = var;

   return id;
}

S32 FuncVars::lookup(StringTableEntry var, S32 lineNumber)
{
   std::unordered_map<StringTableEntry, Var>::iterator found = vars.find(var);
   
   if (found == vars.end())
   {
      const char* str = avar("Script Warning: Variable %s referenced before used when compiling script. File: %s Line: %d", var, CodeBlock::smCurrentParser->getCurrentFile(), lineNumber);
      scriptErrorHandler(str);
      
      return assign(var, TypeReqString, lineNumber, false);
   }
   
   return found->second.reg;
}

TypeReq FuncVars::lookupType(StringTableEntry var, S32 lineNumber)
{
   std::unordered_map<StringTableEntry, Var>::iterator found = vars.find(var);

   if (found == vars.end())
   {
      const char* str = avar("Script Warning: Variable %s referenced before used when compiling script. File: %s Line: %d", var, CodeBlock::smCurrentParser->getCurrentFile(), lineNumber);
      scriptErrorHandler(str);
      
      assign(var, TypeReqString, lineNumber, false);
      return vars.find(var)->second.currentType;
   }
   
   return found->second.currentType;
}

void FuncVars::clear()
{
   vars.clear();
   variableNameMap.clear();
   counter = 0;
}

//-------------------------------------------------------------------------


U32 CompilerStringTable::add(const char *str, bool caseSens, bool tag)
{
   // Is it already in?
   Entry **walk;
   for (walk = &list; *walk; walk = &((*walk)->next))
   {
      if ((*walk)->tag != tag)
         continue;

      if (caseSens)
      {
         if (!String::compare((*walk)->string, str))
            return (*walk)->start;
      }
      else
      {
         if (!dStricmp((*walk)->string, str))
            return (*walk)->start;
      }
   }

   // Write it out.
   Entry *newStr = (Entry *)consoleAlloc(sizeof(Entry));
   *walk = newStr;
   newStr->next = NULL;
   newStr->start = totalLen;
   U32 len = dStrlen(str) + 1;
   if (tag && len < 7) // alloc space for the numeric tag 1 for tag, 5 for # and 1 for nul
      len = 7;
   totalLen += len;
   newStr->string = (char *)consoleAlloc(len);
   newStr->len = len;
   newStr->tag = tag;
   dStrcpy(newStr->string, str, len);

   // Put into the hash table.
   hashTable[str] = newStr;

   return newStr->start;
}

U32 CompilerStringTable::addIntString(U32 value)
{
   dSprintf(buf, sizeof(buf), "%d", value);
   return add(buf);
}

U32 CompilerStringTable::addFloatString(F64 value)
{
   dSprintf(buf, sizeof(buf), "%g", value);
   return add(buf);
}

void CompilerStringTable::reset()
{
   list = NULL;
   totalLen = 0;
}

char *CompilerStringTable::build()
{
   char *ret = new char[totalLen];
   dMemset(ret, 0, totalLen);
   for (Entry *walk = list; walk; walk = walk->next)
      dStrcpy(ret + walk->start, walk->string, totalLen - walk->start);
   return ret;
}

void CompilerStringTable::write(Stream &st)
{
   st.write(totalLen);
   for (Entry *walk = list; walk; walk = walk->next)
      st.write(walk->len, walk->string);
}

//------------------------------------------------------------

void CompilerLocalVariableToRegisterMappingTable::add(StringTableEntry functionName, StringTableEntry namespaceName, StringTableEntry varName)
{
   StringTableEntry funcLookupTableName = StringTable->insert(avar("%s::%s", namespaceName, functionName));

   localVarToRegister[funcLookupTableName].varList.push_back(varName);;
}

S32 CompilerLocalVariableToRegisterMappingTable::lookup(StringTableEntry namespaceName, StringTableEntry functionName, StringTableEntry varName)
{
   StringTableEntry funcLookupTableName = StringTable->insert(avar("%s::%s", namespaceName, functionName));

   auto functionPosition = localVarToRegister.find(funcLookupTableName);
   if (functionPosition != localVarToRegister.end())
   {
      const auto& table = localVarToRegister[funcLookupTableName].varList;
      auto varPosition = std::find(table.begin(), table.end(), varName);
      if (varPosition != table.end())
      {
         return std::distance(table.begin(), varPosition);
      }
   }

   Con::errorf("Unable to find local variable %s in function name %s", varName, funcLookupTableName);
   return -1;
}

CompilerLocalVariableToRegisterMappingTable CompilerLocalVariableToRegisterMappingTable::copy()
{
   // Trivilly copyable as its all plain old data and using STL containers... (We want a deep copy though!)
   CompilerLocalVariableToRegisterMappingTable table;
   table.localVarToRegister = localVarToRegister;
   return table;
}

void CompilerLocalVariableToRegisterMappingTable::reset()
{
   localVarToRegister.clear();
}

void CompilerLocalVariableToRegisterMappingTable::write(Stream& stream)
{
   stream.write((U32)localVarToRegister.size());

   for (const auto& pair : localVarToRegister)
   {
      StringTableEntry functionName = pair.first;
      stream.writeString(functionName);

      const auto& localVariableTableForFunction = localVarToRegister[functionName].varList;
      stream.write((U32)localVariableTableForFunction.size());

      for (const StringTableEntry& varName : localVariableTableForFunction)
      {
         stream.writeString(varName);
      }
   }
}

//------------------------------------------------------------

U32 CompilerFloatTable::add(F64 value)
{
   Entry **walk;
   U32 i = 0;
   for (walk = &list; *walk; walk = &((*walk)->next), i++)
      if (value == (*walk)->val)
         return i;
   Entry *newFloat = (Entry *)consoleAlloc(sizeof(Entry));
   newFloat->val = value;
   newFloat->next = NULL;
   count++;
   *walk = newFloat;
   return count - 1;
}
void CompilerFloatTable::reset()
{
   list = NULL;
   count = 0;
}
F64 *CompilerFloatTable::build()
{
   F64 *ret = new F64[count];
   U32 i = 0;
   for (Entry *walk = list; walk; walk = walk->next, i++)
      ret[i] = walk->val;
   return ret;
}

void CompilerFloatTable::write(Stream &st)
{
   st.write(count);
   for (Entry *walk = list; walk; walk = walk->next)
      st.write(walk->val);
}

//------------------------------------------------------------

void CompilerIdentTable::reset()
{
   list = NULL;
}

void CompilerIdentTable::add(StringTableEntry ste, U32 ip)
{
   U32 index = gGlobalStringTable.add(ste, false);
   Entry *newEntry = (Entry *)consoleAlloc(sizeof(Entry));
   newEntry->offset = index;
   newEntry->ip = ip;
   for (Entry *walk = list; walk; walk = walk->next)
   {
      if (walk->offset == index)
      {
         newEntry->nextIdent = walk->nextIdent;
         walk->nextIdent = newEntry;
         return;
      }
   }
   newEntry->next = list;
   list = newEntry;
   newEntry->nextIdent = NULL;
}

void CompilerIdentTable::write(Stream &st)
{
   U32 count = 0;
   Entry * walk;
   for (walk = list; walk; walk = walk->next)
      count++;
   st.write(count);
   for (walk = list; walk; walk = walk->next)
   {
      U32 ec = 0;
      Entry * el;
      for (el = walk; el; el = el->nextIdent)
         ec++;
      st.write(walk->offset);
      st.write(ec);
      for (el = walk; el; el = el->nextIdent)
         st.write(el->ip);
   }
}

//-------------------------------------------------------------------------

U8 *CodeStream::allocCode(U32 sz)
{
   U8 *ptr = NULL;
   if (mCodeHead)
   {
      const U32 bytesLeft = BlockSize - mCodeHead->size;
      if (bytesLeft > sz)
      {
         ptr = mCodeHead->data + mCodeHead->size;
         mCodeHead->size += sz;
         return ptr;
      }
   }

   CodeData *data = new CodeData;
   data->data = (U8*)dMalloc(BlockSize);
   data->size = sz;
   data->next = NULL;

   if (mCodeHead)
      mCodeHead->next = data;
   mCodeHead = data;
   if (mCode == NULL)
      mCode = data;
   return data->data;
}

//-------------------------------------------------------------------------

void CodeStream::fixLoop(U32 loopBlockStart, U32 breakPoint, U32 continuePoint)
{
   AssertFatal(mFixStack.size() > 0, "Fix stack mismatch");

   U32 fixStart = mFixStack[mFixStack.size() - 1];
   for (U32 i = fixStart; i<mFixList.size(); i += 2)
   {
      FixType type = (FixType)mFixList[i + 1];

      U32 fixedIp = 0;
      bool valid = true;

      switch (type)
      {
         case FIXTYPE_LOOPBLOCKSTART:
            fixedIp = loopBlockStart;
            break;
         case FIXTYPE_BREAK:
            fixedIp = breakPoint;
            break;
         case FIXTYPE_CONTINUE:
            fixedIp = continuePoint;
            break;
         default:
            //Con::warnf("Address %u fixed as %u", mFixList[i], mFixList[i+1]);
            valid = false;
            break;
      }

      if (valid)
      {
         patch(mFixList[i], fixedIp);
      }
   }
}

//-------------------------------------------------------------------------

void CodeStream::emitCodeStream(U32 *size, U32 **stream, U32 **lineBreaks)
{
   // Alloc stream
   U32 numLineBreaks = getNumLineBreaks();
   *stream = new U32[mCodePos + (numLineBreaks * 2)];
   dMemset(*stream, '\0', mCodePos + (numLineBreaks * 2));
   *size = mCodePos;

   // Dump chunks & line breaks
   U32 outBytes = mCodePos * sizeof(U32);
   U8 *outPtr = *((U8**)stream);
   for (CodeData *itr = mCode; itr != NULL; itr = itr->next)
   {
      U32 bytesToCopy = itr->size > outBytes ? outBytes : itr->size;
      dMemcpy(outPtr, itr->data, bytesToCopy);
      outPtr += bytesToCopy;
      outBytes -= bytesToCopy;
   }

   *lineBreaks = *stream + mCodePos;
   dMemcpy(*lineBreaks, mBreakLines.address(), sizeof(U32) * mBreakLines.size());

   // Apply patches on top
   for (U32 i = 0; i<mPatchList.size(); i++)
   {
      PatchEntry &e = mPatchList[i];
      (*stream)[e.addr] = e.value;
   }
}

//-------------------------------------------------------------------------

void CodeStream::reset()
{
   mCodePos = 0;
   mFixStack.clear();
   mFixLoopStack.clear();
   mFixList.clear();
   mBreakLines.clear();

   // Pop down to one code block
   CodeData *itr = mCode ? mCode->next : NULL;
   while (itr != NULL)
   {
      CodeData *next = itr->next;
      dFree(itr->data);
      delete(itr);
      itr = next;
   }

   if (mCode)
   {
      mCode->size = 0;
      mCode->next = NULL;
      mCodeHead = mCode;
   }
}