// 格式化错误并统一打印异常与帮助信息。

#include "utils/Log.h"

#include <ostream>
#include <string>

namespace {

bool IsCLIError(const std::string_view msg) {
  return HasErrorPrefix(msg, "cli");
}

}  // namespace

void LogInfo(const std::string_view msg, std::ostream& os) {
  os << "[info] " << msg << "\n";
}

void LogError(const std::string_view msg, std::ostream& os) {
  os << "[error] " << msg << "\n";
}

std::string FormatError(const std::string_view stage,
                        const std::string_view msg) {
  return "[" + std::string(stage) + "] " + std::string(msg);
}

std::string FormatErrorAt(const std::string_view stage, const std::size_t line,
                          const std::size_t column,
                          const std::string_view msg) {
  return "[" + std::string(stage) + "] @" + std::to_string(line) + ":" +
         std::to_string(column) + " - " + std::string(msg);
}

bool HasErrorPrefix(const std::string_view msg, const std::string_view stage) {
  const std::string prefix = "[" + std::string(stage) + "]";
  return msg.rfind(prefix, 0) == 0;
}

void PrintException(std::ostream& os, const std::exception& ex) {
  LogError(ex.what(), os);
  if (IsCLIError(ex.what())) {
    os << "\n";
    PrintHelp(os);
  }
}

void PrintHelp(std::ostream& os) {
  os << "SysY Compiler\n"
     << "\n"
     << "用法:\n"
     << "  compiler <input.sy> -IR -o <output.ll> [-O1]    # 输出 IR\n"
     << "  compiler <input.sy> -S  -o <output.s>  [-O1]    # 输出汇编\n"
     << "\n"
     << "选项:\n"
     << "  -IR            输出中间代码（IR 文本）\n"
     << "  -S             输出 AArch64 汇编码\n"
     << "  -o <file>      输出文件（默认 stdout）\n"
     << "  -O1            启用 IR 优化（Mem2Reg + 标量优化）\n"
     << "  -h, --help     打印帮助信息并退出\n"
     << "\n"
     << "兼容格式（仍可使用）:\n"
     << "  --emit-ir      同 -IR\n"
     << "  --emit-asm     同 -S\n"
     << "\n"
     << "示例:\n"
     << "  compiler test.sy -IR -o test.ll -O1     # 生成优化 IR\n"
     << "  compiler test.sy -S  -o test.s  -O1     # 生成优化汇编\n"
     << "  compiler test.sy -IR                    # IR 输出到 stdout\n";
}