// Copyright © 2019-2023
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#pragma once

#include <vector>
#include <simobject.h>
#include "types.h"
#include "emulator.h"
#include "pipeline.h"
#include "cache_sim.h"
#include "local_mem.h"
#include "ibuffer.h"
#include "scoreboard.h"
#include "operand.h"
#include "dispatcher.h"
#include "func_unit.h"
#include "mem_coalescer.h"
#include "VX_config.h"

namespace vortex {

class Socket;
class Arch;
class DCRS;

using TraceArbiter = Arbiter<instr_trace_t*>;

class Core : public SimObject<Core> {
public:
  struct PerfStats {
    uint64_t cycles;
    uint64_t instrs;
    uint64_t sched_idle;
    uint64_t sched_stalls;
    uint64_t ibuf_stalls;
    uint64_t scrb_stalls;
    uint64_t opds_stalls;
    uint64_t scrb_alu;
    uint64_t scrb_fpu;
    uint64_t scrb_lsu;
    uint64_t scrb_sfu;
    uint64_t scrb_csrs;
    uint64_t scrb_wctl;
    uint64_t ifetches;
    uint64_t loads;
    uint64_t stores;
    uint64_t ifetch_latency;
    uint64_t load_latency;

    PerfStats()
      : cycles(0)
      , instrs(0)
      , sched_idle(0)
      , sched_stalls(0)
      , ibuf_stalls(0)
      , scrb_stalls(0)
      , opds_stalls(0)
      , scrb_alu(0)
      , scrb_fpu(0)
      , scrb_lsu(0)
      , scrb_sfu(0)
      , scrb_csrs(0)
      , scrb_wctl(0)
      , ifetches(0)
      , loads(0)
      , stores(0)
      , ifetch_latency(0)
      , load_latency(0)
    {}
  };

  std::vector<SimPort<MemReq>> icache_req_ports;
  std::vector<SimPort<MemRsp>> icache_rsp_ports;

  std::vector<SimPort<MemReq>> dcache_req_ports;
  std::vector<SimPort<MemRsp>> dcache_rsp_ports;

  Core(const SimContext& ctx,
       uint32_t core_id,
       Socket* socket,
       const Arch &arch,
       const DCRS &dcrs);

  ~Core();

  void reset();

  void tick();

  void attach_ram(RAM* ram);
#ifdef VM_ENABLE
  void set_satp(uint64_t satp);
#endif

  bool running() const;

  void resume(uint32_t wid);

  bool barrier(uint32_t bar_id, uint32_t count, uint32_t wid);

  bool wspawn(uint32_t num_warps, Word nextPC);

  uint32_t id() const {
    return core_id_;
  }

  const Arch& arch() const {
    return arch_;
  }

  Socket* socket() const {
    return socket_;
  }

  const LocalMem::Ptr& local_mem() const {
    return local_mem_;
  }

  const MemCoalescer::Ptr& mem_coalescer(uint32_t idx) const {
    return mem_coalescers_.at(idx);
  }

  const PerfStats& perf_stats() const {
    return perf_stats_;
  }

  int get_exitcode() const;

private:

  void schedule();
  void fetch();
  void decode();
  void issue();
  void execute();
  void commit();

  uint32_t core_id_;
  Socket* socket_;
  const Arch& arch_;

  Emulator emulator_;

  std::vector<IBuffer> ibuffers_;
  Scoreboard scoreboard_;
  std::vector<Operand::Ptr> operands_;
  std::vector<Dispatcher::Ptr> dispatchers_;
  std::vector<FuncUnit::Ptr> func_units_;
  LocalMem::Ptr local_mem_;
  std::vector<LocalMemSwitch::Ptr> lmem_switch_;
  std::vector<MemCoalescer::Ptr> mem_coalescers_;

  PipelineLatch fetch_latch_;
  PipelineLatch decode_latch_;

  HashTable<instr_trace_t*> pending_icache_;
  uint64_t pending_instrs_;

  uint64_t pending_ifetches_;

  PerfStats perf_stats_;

  std::vector<TraceArbiter::Ptr> commit_arbs_;

  uint32_t commit_exe_;
  uint32_t ibuffer_idx_;

  friend class LsuUnit;
  friend class AluUnit;
  friend class FpuUnit;
  friend class SfuUnit;
  friend class TcuUnit;
};

} // namespace vortex