//
// Created by erki on 16.02.21.
//

#include "OperationFinder.hpp"

#include <iostream>

#include "ASTHelpers.hpp"

using namespace clang;
using namespace clang::ast_matchers;

namespace
{

std::string ResolveTypeName(const QualType& t)
{
  if (t->isTypedefNameType())
  {
    const TypedefType* tdt = cast<TypedefType>(t);
    assert(tdt);
    llvm::outs() << "Typedef type: " << t.getAsString()
                 << ", underlying: " << tdt->desugar().getAsString()
                 << ".";

    return tdt->desugar().getAsString();
  }
  else if (t->isBuiltinType())
  {
    llvm::outs() << "Builtin type: " << t.getAsString() << ".";
    return t.getAsString();
  }
  else
  {
    llvm::outs() << "Other type: " << t.getAsString() << ".";
    return t.getAsString();
  }
};

}

OperationFinder::OperationFinder(IOperationOutput* storage)
  : _storage(storage)
{
  assert(storage);
}

void OperationFinder::processArithmetic(const clang::BinaryOperator* op, const clang::SourceManager& source_manager)
{
  const auto [file_name, line_number, column_number] = resolveLocations(op, source_manager);

  llvm::outs()  << file_name << ":"
                << line_number << ":"
                << column_number << ":"
                << "Binary arithmetic: Type: " << getOpcode(op) << " LHS: ";

  OperationLog log;
  log.line = line_number;
  log.entry_type = OperationLog::BasicOperation::TYPE_NAME;
  log.entry = _createBasicOperationLogEntry(op, op->getLHS(), op->getRHS());
  log.current_for_loops = _for_loop_stack;
  log.is_fallthrough = _in_fallthrough;

  _storage->pushOperation(file_name, std::move(log));

  llvm::outs() << "\n";
}

void OperationFinder::processUnaryArithmetic(const clang::UnaryOperator* op, const clang::SourceManager& source_manager)
{
  const Expr* lhs = op->getExprStmt();

  assert(op);
  assert(lhs);

  const auto [file_name, line_number, column_number] = resolveLocations(op, source_manager);

  llvm::outs()  << file_name << ":"
                << line_number << ":"
                << column_number << ":"
                << "Unary arithmetic: Type: " << getOpcode(op) << " LHS: ";

  OperationLog log;
  log.line = line_number;
  log.entry_type = OperationLog::BasicOperation::TYPE_NAME;
  log.entry = _createBasicOperationLogEntry(op, lhs, nullptr);
  log.current_for_loops = _for_loop_stack;
  log.is_fallthrough = _in_fallthrough;

  _storage->pushOperation(file_name, std::move(log));

  llvm::outs() << "\n";
}

void OperationFinder::processFunctionCall(const clang::CallExpr* call, const SourceManager& source_manager)
{
  const FunctionDecl* func = call->getDirectCallee();

  assert(func);

  const auto [file_name, line_number, column_number] = resolveLocations(call, source_manager);

  const std::string res_type = ResolveTypeName(func->getType());
  const std::string func_name = func->getNameAsString();

  llvm::outs()  << file_name << ":"
                << line_number << ":"
                << column_number << ":"
                << "Function call: name: " << func_name << " Restype: "
                << res_type << "\n";

  auto func_call = std::make_unique<OperationLog::FunctionCall>();
  func_call->function_name = func_name;
  func_call->call_result_type = res_type;

  OperationLog log;
  log.line = line_number;
  log.entry_type = OperationLog::FunctionCall::TYPE_NAME;
  log.entry = std::move(func_call);
  log.current_for_loops = _for_loop_stack;
  log.is_fallthrough = _in_fallthrough;

  _storage->pushOperation(file_name, std::move(log));
}

void OperationFinder::fallthroughBranchEntered()
{
  _in_fallthrough = true;
}

void OperationFinder::fallthroughBranchExited()
{
  _in_fallthrough = false;
}

void OperationFinder::forLoopEntered()
{
  _for_loop_stack.push_back(_next_for_loop_id);

  _next_for_loop_id++;
}

void OperationFinder::forLoopExited()
{
  _for_loop_stack.pop_back();
}

std::unique_ptr<OperationLog::BasicOperation>
        OperationFinder::_createBasicOperationLogEntry(const Expr* source, const Expr* op1, const Expr* op2)
{
  auto log = std::make_unique<OperationLog::BasicOperation>();

  llvm::outs() << "Expression types:\n\tExpression eval type: ";
  log->type_result = ResolveTypeName(source->getType());

  if (op1)
  {
    llvm::outs() << "\n\tLHS eval type: ";
    log->type_lhs = ResolveTypeName(op1->getType());
  }
  if (op2)
  {
    llvm::outs() << "\n\tRHS eval type: ";
    log->type_rhs = ResolveTypeName(op2->getType());
  }

  return log;
}