// vim: set sts=2 ts=8 sw=2 tw=99 et:
// 
// Copyright (C) 2006-2015 AlliedModders LLC
// 
// This file is part of SourcePawn. SourcePawn is free software: you can
// redistribute it and/or modify it under the terms of the GNU General Public
// License as published by the Free Software Foundation, either version 3 of
// the License, or (at your option) any later version.
//
// You should have received a copy of the GNU General Public License along with
// SourcePawn. If not, see http://www.gnu.org/licenses/.
//
#ifndef _INCLUDE_SOURCEPAWN_BASECONTEXT_H_
#define _INCLUDE_SOURCEPAWN_BASECONTEXT_H_

#include "sp_vm_api.h"
#include "scripted-invoker.h"
#include "plugin-runtime.h"
#include "jit_shared.h"

struct HeapTracker
{
  HeapTracker()
   : size(0),
     pBase(nullptr),
     pCur(nullptr)
  {}
  size_t size; 
  ucell_t *pBase; 
  ucell_t *pCur;
};

class PluginContext : public IPluginContext
{
 public:
  PluginContext(PluginRuntime *pRuntime);
  ~PluginContext();

 public: //IPluginContext
  IVirtualMachine *GetVirtualMachine();
  sp_context_t *GetContext();
  sp_context_t *GetCtx();
  bool IsDebugging();
  int SetDebugBreak(void *newpfn, void *oldpfn);
  IPluginDebugInfo *GetDebugInfo();
  int HeapAlloc(unsigned int cells, cell_t *local_addr, cell_t **phys_addr);
  int HeapPop(cell_t local_addr);
  int HeapRelease(cell_t local_addr);
  int FindNativeByName(const char *name, uint32_t *index);
  int GetNativeByIndex(uint32_t index, sp_native_t **native);
  uint32_t GetNativesNum();
  int FindPublicByName(const char *name, uint32_t *index);
  int GetPublicByIndex(uint32_t index, sp_public_t **publicptr);
  uint32_t GetPublicsNum();
  int GetPubvarByIndex(uint32_t index, sp_pubvar_t **pubvar);
  int FindPubvarByName(const char *name, uint32_t *index);
  int GetPubvarAddrs(uint32_t index, cell_t *local_addr, cell_t **phys_addr);
  uint32_t GetPubVarsNum();
  int LocalToPhysAddr(cell_t local_addr, cell_t **phys_addr);
  int LocalToString(cell_t local_addr, char **addr);
  int StringToLocal(cell_t local_addr, size_t chars, const char *source);
  int StringToLocalUTF8(cell_t local_addr, size_t maxbytes, const char *source, size_t *wrtnbytes);
  int PushCell(cell_t value);
  int PushCellArray(cell_t *local_addr, cell_t **phys_addr, cell_t array[], unsigned int numcells);
  int PushString(cell_t *local_addr, char **phys_addr, const char *string);
  int PushCellsFromArray(cell_t array[], unsigned int numcells);
  int BindNatives(const sp_nativeinfo_t *natives, unsigned int num, int overwrite);
  int BindNative(const sp_nativeinfo_t *native);
  int BindNativeToAny(SPVM_NATIVE_FUNC native);
  int Execute(uint32_t code_addr, cell_t *result);
  cell_t ThrowNativeErrorEx(int error, const char *msg, ...);
  cell_t ThrowNativeError(const char *msg, ...);
  IPluginFunction *GetFunctionByName(const char *public_name);
  IPluginFunction *GetFunctionById(funcid_t func_id);
  SourceMod::IdentityToken_t *GetIdentity();
  cell_t *GetNullRef(SP_NULL_TYPE type);
  int LocalToStringNULL(cell_t local_addr, char **addr);
  int BindNativeToIndex(uint32_t index, SPVM_NATIVE_FUNC native);
  int Execute2(IPluginFunction *function, const cell_t *params, unsigned int num_params, cell_t *result);
  IPluginRuntime *GetRuntime();
  int GetLastNativeError();
  cell_t *GetLocalParams();
  void SetKey(int k, void *value);
  bool GetKey(int k, void **value);
  void Refresh();
  void ClearLastNativeError();

 public:
  bool IsInExec();

  static inline size_t offsetOfRp() {
    return offsetof(PluginContext, rp_);
  }
  static inline size_t offsetOfRstkCips() {
    return offsetof(PluginContext, rstk_cips_);
  }
  static inline size_t offsetOfTracker() {
    return offsetof(PluginContext, tracker_);
  }
  static inline size_t offsetOfLastNative() {
    return offsetof(PluginContext, last_native_);
  }
  static inline size_t offsetOfNativeError() {
    return offsetof(PluginContext, native_error_);
  }

  // Return stack logic.
  bool pushReturnCip(cell_t cip) {
    if (rp_ >= SP_MAX_RETURN_STACK)
      return false;
    rstk_cips_[rp_++] = cip;
    return true;
  }
  void popReturnCip() {
    assert(rp_ > 0);
    rp_--;
  }
  cell_t rp() const {
    return rp_;
  }
  cell_t getReturnStackCip(int index) {
    assert(index >= 0 && index < SP_MAX_RETURN_STACK);
    return rstk_cips_[index];
  }

  int popTrackerAndSetHeap();
  int pushTracker(uint32_t amount);

  cell_t invokeNative(ucell_t native_idx, cell_t *params);
  cell_t invokeBoundNative(SPVM_NATIVE_FUNC pfn, cell_t *params);
  int lastNative() const {
    return last_native_;
  }

 private:
  void SetErrorMessage(const char *msg, va_list ap);
  void _SetErrorMessage(const char *msg, ...);

 private:
  cell_t *m_pNullVec;
  cell_t *m_pNullString;
  char m_MsgCache[1024];
  bool m_CustomMsg;
  bool m_InExec;
  PluginRuntime *m_pRuntime;
  sp_context_t m_ctx;
  void *m_keys[4];
  bool m_keys_set[4];

  // Tracker for local HEA growth.
  HeapTracker tracker_;

  // Return stack.
  cell_t rp_;
  cell_t rstk_cips_[SP_MAX_RETURN_STACK];

  // Track the currently executing native index, and any error it throws.
  int32_t last_native_;
  int native_error_;
};

#endif //_INCLUDE_SOURCEPAWN_BASECONTEXT_H_