#include <exception>
#include <fstream>
#include <iostream>
#include <stdexcept>
#include <sstream>

#include "frontend/AntlrDriver.h"
#include "frontend/SyntaxTreePrinter.h"
#if !COMPILER_PARSE_ONLY
#include "ir/IR.h"
#include "ir/passes/PassManager.h"
#include "irgen/IRGen.h"
#include "mir/MIR.h"
#include "sem/Sema.h"
#endif
#include "utils/CLI.h"
#include "utils/Log.h"

int main(int argc, char** argv) {
  try {
    auto opts = ParseCLI(argc, argv);
    if (opts.show_help) {
      PrintHelp(std::cout);
      return 0;
    }

    auto antlr = ParseFileWithAntlr(opts.input);
    bool need_blank_line = false;
    if (opts.emit_parse_tree) {
      PrintSyntaxTree(antlr.tree, antlr.parser.get(), std::cout);
      need_blank_line = true;
    }

#if !COMPILER_PARSE_ONLY
    auto* comp_unit =
        dynamic_cast<SysYParser::CompUnitContext*>(antlr.tree);
    if (!comp_unit) {
      throw std::runtime_error(
          FormatError("main", "语法树根节点不是 compUnit"));
    }

    auto sema = RunSema(*comp_unit);
    auto module = GenerateIR(*comp_unit, sema);

    // 执行优化（如果启用）
    if (opts.optimize) {
      ir::PassManager pass_manager;
      pass_manager.RunScalarOptimizationPasses(module.get());
    }

    // 汇编输出到文件或标准输出
    if (opts.emit_asm) {
      auto machine_module = mir::LowerModuleToMIR(*module);
      mir::RunRegAlloc(*machine_module);
      mir::RunFrameLowering(*machine_module);
      mir::RunPeephole(*machine_module);

      std::ostringstream asm_ss;
      mir::PrintAsm(*machine_module, asm_ss);

      if (!opts.output.empty()) {
        // 写入指定文件（-o 参数）
        std::ofstream ofs(opts.output);
        if (!ofs) {
          throw std::runtime_error(FormatError("main", std::string("无法打开输出文件: ") + opts.output));
        }
        ofs << asm_ss.str();
        ofs.close();
      } else {
        // 输出到标准输出
        if (need_blank_line) {
          std::cout << "\n";
        }
        std::cout << asm_ss.str();
      }
    }

    if (opts.emit_ir) {
      ir::IRPrinter printer;
      if (need_blank_line) {
        std::cout << "\n";
      }
      printer.Print(*module, std::cout);
      need_blank_line = true;
    }
#else
    if (opts.emit_ir || opts.emit_asm) {
      throw std::runtime_error(
          FormatError("main", "当前为 parse-only 构建；IR/汇编输出已禁用"));
    }
#endif
  } catch (const std::exception& ex) {
    PrintException(std::cerr, ex);
    return 1;
  }

  return 0;
}