#include "senior_generator.h"

#include <sstream>
#include <string>
#include <vector>

std::vector<std::string> SeniorGenerator::GenerateQuestions(int count,
                                                          const std::string& username) {
  current_user_ = username;
  std::vector<std::string> questions;
  questions.reserve(count);
  
  for (int i = 0; i < count; ++i) {
    questions.push_back(GenerateSingleQuestion());
  }
  
  return questions;
}

std::string SeniorGenerator::GenerateSingleQuestion() {
  static const std::vector<char> kOperators = {'+', '-', '*', '/'};
  static const std::vector<std::string> kTrigFunctions = {"sin", "cos", "tan"};
  const int operand_count = GetRandomNumber(kMinOperands, kMaxOperands);
  
  std::stringstream ss;
  bool has_trig_function = false;
  
  // 第一个操作数可以是普通数字或三角函数
  if (operand_count == 1 || GetRandomNumber(0, 1)) {
    // 单操作数情况或第一个操作数是三角函数
    const int trig_index = GetRandomNumber(0, kTrigFunctions.size() - 1);
    ss << kTrigFunctions[trig_index] << "(" 
       << GetRandomNumber(kMinNumber, kMaxAngle) << "°)";
    has_trig_function = true;
  } else {
    // 第一个操作数是普通数字
    ss << GetRandomNumber(kMinNumber, kMaxNumber);
  }
  
  // 添加后续操作数
  for (int i = 1; i < operand_count; ++i) {
    const char op = GetRandomOperator(kOperators);
    
    // 随机决定是添加普通数字还是三角函数
    if (!has_trig_function || GetRandomNumber(0, 1)) {
      const int trig_index = GetRandomNumber(0, kTrigFunctions.size() - 1);
      ss << " " << op << " " << kTrigFunctions[trig_index] << "(" 
         << GetRandomNumber(kMinNumber, kMaxAngle) << "°)";
      has_trig_function = true;
    } else {
      ss << " " << op << " " << GetRandomNumber(kMinNumber, kMaxNumber);
    }
  }
  
  // 确保至少有一个三角函数
  if (!has_trig_function) {
    const char op = GetRandomOperator(kOperators);
    const int trig_index = GetRandomNumber(0, kTrigFunctions.size() - 1);
    ss << " " << op << " " << kTrigFunctions[trig_index] << "(" 
       << GetRandomNumber(kMinNumber, kMaxAngle) << "°)";
  }
  
  ss << " = ?";
  return ss.str();
}

bool SeniorGenerator::MeetsDifficultyRequirements(const std::string& question) {
  // 高中题目至少包含一个三角函数
  return question.find("sin") != std::string::npos ||
         question.find("cos") != std::string::npos ||
         question.find("tan") != std::string::npos;
}