"""
问题队列类定义
管理问题列表，提供各种排序和调度方法
"""

from typing import List, Dict, Any, Optional, Callable, Iterator
from enum import Enum
from question import Question, SamplingRecord
import json
import os

class QueueStrategy(Enum):
    """队列策略枚举"""
    FCFS = "fcfs"           # First Come First Serve
    SJF = "sjf"             # Shortest Job First
    ROUND_ROBIN = "rr"      # Round Robin
    PRIORITY = "priority"   # Priority based
    CUSTOM = "custom"       # Custom sorting

class QuestionQueue:
    """问题队列类"""
    
    def __init__(self, questions: Optional[List[Question]] = None):
        """
        初始化问题队列
        
        Args:
            questions: 问题列表
        """
        self.questions: List[Question] = questions or []
        self.current_index: int = 0
        self.strategy: QueueStrategy = QueueStrategy.FCFS
        self.custom_sort_key: Optional[Callable[[Question], Any]] = None
        
        # 队列统计信息
        self.total_processed: int = 0
        self.total_tokens_used: int = 0
        self.total_correct: int = 0
    
    def add_question(self, question: Question) -> None:
        """添加问题到队列"""
        self.questions.append(question)
    
    def add_questions(self, questions: List[Question]) -> None:
        """批量添加问题"""
        self.questions.extend(questions)
    
    def remove_question(self, question_id: int) -> bool:
        """根据ID移除问题"""
        for i, question in enumerate(self.questions):
            if question.question_id == question_id:
                self.questions.pop(i)
                return True
        return False
    
    def get_question(self, question_id: int) -> Optional[Question]:
        """根据ID获取问题"""
        for question in self.questions:
            if question.question_id == question_id:
                return question
        return None
    
    def set_strategy(self, strategy: QueueStrategy, 
                    custom_sort_key: Optional[Callable[[Question], Any]] = None) -> None:
        """
        设置队列策略
        
        Args:
            strategy: 队列策略
            custom_sort_key: 自定义排序键函数
        """
        self.strategy = strategy
        self.custom_sort_key = custom_sort_key
        self.current_index = 0
    
    def sort_questions(self) -> None:
        """根据当前策略排序问题"""
        if self.strategy == QueueStrategy.FCFS:
            # FCFS: 保持原始顺序
            pass
        elif self.strategy == QueueStrategy.SJF:
            # SJF: 按平均token数量排序
            self.questions.sort(key=lambda q: q.avg_tokens)
        elif self.strategy == QueueStrategy.ROUND_ROBIN:
            # Round Robin: 保持原始顺序
            pass
        elif self.strategy == QueueStrategy.PRIORITY:
            # Priority: 按准确率排序（准确率低的优先）
            self.questions.sort(key=lambda q: q.accuracy)
        elif self.strategy == QueueStrategy.CUSTOM and self.custom_sort_key:
            # Custom: 使用自定义排序键
            self.questions.sort(key=self.custom_sort_key)
        
        self.current_index = 0
    
    def get_next_question(self) -> Optional[Question]:
        """获取下一个要处理的问题"""
        if not self.questions:
            return None
        
        if self.strategy == QueueStrategy.ROUND_ROBIN:
            # Round Robin: 循环访问
            question = self.questions[self.current_index]
            self.current_index = (self.current_index + 1) % len(self.questions)
            return question
        else:
            # 其他策略: 按排序顺序访问
            if self.current_index < len(self.questions):
                question = self.questions[self.current_index]
                self.current_index += 1
                return question
            return None
    
    def reset_iterator(self) -> None:
        """重置迭代器位置"""
        self.current_index = 0
    
    def get_questions_iterator(self) -> Iterator[Question]:
        """获取问题迭代器"""
        if self.strategy == QueueStrategy.ROUND_ROBIN:
            # Round Robin: 无限循环
            while True:
                for question in self.questions:
                    yield question
        else:
            # 其他策略: 单次遍历
            for question in self.questions:
                yield question
    
    def add_sampling_record(self, question_id: int, record: SamplingRecord) -> bool:
        """
        为指定问题添加采样记录
        
        Args:
            question_id: 问题ID
            record: 采样记录
        
        Returns:
            是否成功添加
        """
        question = self.get_question(question_id)
        if question:
            question.add_sampling_record(record)
            return True
        return False
    
    def get_queue_stats(self) -> Dict[str, Any]:
        """获取队列统计信息"""
        if not self.questions:
            return {
                'total_questions': 0,
                'total_processed': 0,
                'total_tokens_used': 0,
                'total_correct': 0,
                'overall_accuracy': 0.0,
                'avg_tokens_per_question': 0.0
            }
        
        total_questions = len(self.questions)
        total_processed = sum(q.total_runs for q in self.questions)
        total_tokens_used = sum(q.total_tokens for q in self.questions)
        total_correct = sum(q.correct_count for q in self.questions)
        
        overall_accuracy = total_correct / total_questions if total_questions > 0 else 0.0
        avg_tokens_per_question = total_tokens_used / total_questions if total_questions > 0 else 0.0
        
        return {
            'total_questions': total_questions,
            'total_processed': total_processed,
            'total_tokens_used': total_tokens_used,
            'total_correct': total_correct,
            'overall_accuracy': overall_accuracy,
            'avg_tokens_per_question': avg_tokens_per_question,
            'strategy': self.strategy.value,
            'current_index': self.current_index
        }
    
    def get_questions_by_criteria(self, 
                                 min_accuracy: Optional[float] = None,
                                 max_accuracy: Optional[float] = None,
                                 min_tokens: Optional[float] = None,
                                 max_tokens: Optional[float] = None,
                                 min_runs: Optional[int] = None,
                                 max_runs: Optional[int] = None) -> List[Question]:
        """
        根据条件筛选问题
        
        Args:
            min_accuracy: 最小准确率
            max_accuracy: 最大准确率
            min_tokens: 最小平均token数
            max_tokens: 最大平均token数
            min_runs: 最小运行次数
            max_runs: 最大运行次数
        
        Returns:
            符合条件的问题列表
        """
        filtered_questions = []
        
        for question in self.questions:
            # 检查准确率
            if min_accuracy is not None and question.accuracy < min_accuracy:
                continue
            if max_accuracy is not None and question.accuracy > max_accuracy:
                continue
            
            # 检查平均token数
            if min_tokens is not None and question.avg_tokens < min_tokens:
                continue
            if max_tokens is not None and question.avg_tokens > max_tokens:
                continue
            
            # 检查运行次数
            if min_runs is not None and question.total_runs < min_runs:
                continue
            if max_runs is not None and question.total_runs > max_runs:
                continue
            
            filtered_questions.append(question)
        
        return filtered_questions
    
    def save_to_file(self, filepath: str) -> None:
        """保存队列到文件"""
        data = {
            'questions': [q.to_dict() for q in self.questions],
            'strategy': self.strategy.value,
            'current_index': self.current_index,
            'stats': self.get_queue_stats()
        }
        
        os.makedirs(os.path.dirname(filepath), exist_ok=True)
        with open(filepath, 'w', encoding='utf-8') as f:
            json.dump(data, f, ensure_ascii=False, indent=2)
    
    @classmethod
    def load_from_file(cls, filepath: str) -> 'QuestionQueue':
        """从文件加载队列"""
        with open(filepath, 'r', encoding='utf-8') as f:
            data = json.load(f)
        
        questions = [Question.from_dict(q_data) for q_data in data['questions']]
        queue = cls(questions)
        queue.strategy = QueueStrategy(data['strategy'])
        queue.current_index = data.get('current_index', 0)
        
        return queue
    
    def to_dict(self) -> Dict[str, Any]:
        """转换为字典格式"""
        return {
            'questions': [q.to_dict() for q in self.questions],
            'strategy': self.strategy.value,
            'current_index': self.current_index,
            'stats': self.get_queue_stats()
        }
    
    def __len__(self) -> int:
        """返回队列长度"""
        return len(self.questions)
    
    def __getitem__(self, index: int) -> Question:
        """索引访问"""
        return self.questions[index]
    
    def __iter__(self) -> Iterator[Question]:
        """迭代器"""
        return iter(self.questions)
    
    def copy(self) -> 'QuestionQueue':
        """创建队列的深拷贝"""
        copied_questions = [q.copy() for q in self.questions]
        copied_queue = QuestionQueue(copied_questions)
        copied_queue.strategy = self.strategy
        copied_queue.current_index = self.current_index
        copied_queue.custom_sort_key = self.custom_sort_key
        return copied_queue