#!/usr/bin/env python3
"""
高响应比优先调度算法 (HRRN)
Highest Response Ratio Next
"""

from typing import List, Dict

from base import (
    Process,
    ProcessScheduler,
    generate_random_processes,
    print_processes
)


class HRRNScheduler(ProcessScheduler):
    """
    高响应比优先调度 (Highest Response Ratio Next)
    
    响应比 = (等待时间 + 服务时间) / 服务时间
           = 1 + 等待时间 / 服务时间
    
    特点：
        - 非抢占式
        - 综合考虑了等待时间和服务时间
        - 避免长作业饥饿问题
    """
    
    def calculate_response_ratio(self, p: Process, current_time: int) -> float:
        """计算响应比"""
        waiting_time = current_time - p.arrival_time
        return 1 + (waiting_time / p.burst_time) if p.burst_time > 0 else float('inf')
    
    def schedule(self) -> Dict:
        """HRRN 调度算法"""
        processes = sorted(self.processes, key=lambda p: p.arrival_time)
        ready_queue: List[Process] = []
        current_time = 0
        completed = 0
        
        while completed < len(processes):
            # 添加所有到达的进程
            for p in processes:
                if p.arrival_time <= current_time and p not in ready_queue and p not in self.results:
                    ready_queue.append(p)
            
            if ready_queue:
                # 计算每个进程的响应比，选择最高的
                ready_queue.sort(
                    key=lambda p: self.calculate_response_ratio(p, current_time),
                    reverse=True  # 响应比高优先
                )
                p = ready_queue.pop(0)
                
                p.start_time = current_time
                current_time += p.burst_time
                self.calculate_metrics(p, current_time)
                self.results.append(p)
                completed += 1
            else:
                current_time += 1
        
        return self.print_results("HRRN (高响应比优先)")


if __name__ == "__main__":
    processes = generate_random_processes(n=5, seed=42)
    print_processes(processes, "测试数据")
    
    scheduler = HRRNScheduler(processes)
    scheduler.schedule()