//===--- stkrc.cpp --- The Stacker Compiler -------------------------------===//
// 
//                     The LLVM Compiler Infrastructure
//
// This file was developed by Reid Spencer and donated to the LLVM research 
// group and is distributed under the University of Illinois Open Source 
// License. See LICENSE.TXT for details.
// 
//===----------------------------------------------------------------------===//
//
//  This is the "main" program for the Stacker Compiler. It is simply a utility
//  that invokes the StackerCompiler::compile method (see StackerCompiler.cpp)
//
//  To get help using this utility, you can invoke it with:
//   stkrc --help         - Output information about command line switches
//
// 
//===------------------------------------------------------------------------===

#include "../../lib/compiler/StackerCompiler.h"
#include "llvm/Assembly/Parser.h"
#include "llvm/Bytecode/Writer.h"
#include "llvm/Analysis/Verifier.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/System/Signals.h"
#include <fstream>
#include <iostream>
#include <memory>

using namespace llvm;

static cl::opt<std::string> 
InputFilename(cl::Positional, cl::desc("<input .st file>"), cl::init("-"));

static cl::opt<std::string>
OutputFilename("o", cl::desc("Override output filename"), 
	cl::value_desc("filename"));

static cl::opt<bool>
Force("f", cl::desc("Overwrite output files"));

static cl::opt<uint32_t>
StackSize("s", cl::desc("Specify program maximum stack size"),
	cl::init(1024), cl::value_desc("stack size"));

static cl::opt<bool>
DumpAsm("d", cl::desc("Print LLVM Assembly as parsed"), cl::Hidden);

#ifdef PARSE_DEBUG 
static cl::opt<bool>
ParseDebug("g", cl::desc("Turn on Bison Debugging"), cl::Hidden);
#endif

#ifdef FLEX_DEBUG
static cl::opt<bool>
FlexDebug("x", cl::desc("Turn on Flex Debugging"), cl::Hidden);
#endif

static cl::opt<bool>
EchoSource("e", cl::desc("Print Stacker Source as parsed"), cl::Hidden);

int main(int argc, char **argv) 
{
  cl::ParseCommandLineOptions(argc, argv, " stacker .st -> .bc compiler\n");

  std::ostream *Out = 0;
  StackerCompiler compiler;
  try 
  {
#ifdef PARSE_DEBUG
    {
	extern int Stackerdebug;
	Stackerdebug = ParseDebug;
    }
#endif
#ifdef FLEX_DEBUG
    {
	extern int Stacker_flex_debug;
	Stacker_flex_debug = FlexDebug;
    }
#endif
    // Parse the file now...
    
    std::auto_ptr<Module> M ( 
	compiler.compile(InputFilename,EchoSource, StackSize) );
    if (M.get() == 0) {
      std::cerr << argv[0] << ": assembly didn't read correctly.\n";
      return 1;
    }

    if (verifyModule(*M.get())) {
      std::cerr << argv[0]
                << ": assembly parsed, but does not verify as correct!\n";
      return 1;
    }
  
    if (DumpAsm) std::cerr << "Here's the assembly:\n" << M.get();

    if (OutputFilename != "") {   // Specified an output filename?
      if (OutputFilename != "-") {  // Not stdout?
        if (!Force && std::ifstream(OutputFilename.c_str())) {
          // If force is not specified, make sure not to overwrite a file!
          std::cerr << argv[0] << ": error opening '" << OutputFilename
                    << "': file exists!\n"
                    << "Use -f command line argument to force output\n";
          return 1;
        }
        Out = new std::ofstream(OutputFilename.c_str());
      } else {                      // Specified stdout
	Out = &std::cout;       
      }
    } else {
      if (InputFilename == "-") {
	OutputFilename = "-";
	Out = &std::cout;
      } else {
	std::string IFN = InputFilename;
	int Len = IFN.length();
	if (IFN[Len-3] == '.' && IFN[Len-2] == 's' && IFN[Len-1] == 't') {
	  // Source ends in .ll
	  OutputFilename = std::string(IFN.begin(), IFN.end()-3);
        } else {
	  OutputFilename = IFN;   // Append a .bc to it
	}
	OutputFilename += ".bc";

        if (!Force && std::ifstream(OutputFilename.c_str())) {
          // If force is not specified, make sure not to overwrite a file!
          std::cerr << argv[0] << ": error opening '" << OutputFilename
                    << "': file exists!\n"
                    << "Use -f command line argument to force output\n";
          return 1;
        }

	Out = new std::ofstream(OutputFilename.c_str());
        // Make sure that the Out file gets unlinked from the disk if we get a
        // SIGINT
        sys::RemoveFileOnSignal(OutputFilename);
      }
    }
  
    if (!Out->good()) {
      std::cerr << argv[0] << ": error opening " << OutputFilename << "!\n";
      return 1;
    }
   
    WriteBytecodeToFile(M.get(), *Out);
  } catch (const ParseException &E) {
    std::cerr << argv[0] << ": " << E.getMessage() << "\n";
    return 1;
  }

  if (Out != &std::cout) delete Out;
  return 0;
}