#!/usr/bin/env python3
"""
@file timing_analyzer.py
@brief Timing analyzer for Automotive RTOS
"""

import os
import re
import sys
import argparse
import json
from collections import defaultdict
from pathlib import Path

class TimingAnalyzer:
    """Analyze timing requirements and performance"""

    def __init__(self, project_root):
        self.project_root = Path(project_root)
        self.tasks = {}
        self.timing_data = defaultdict(list)
        self.violations = []

    def analyze_task_configuration(self):
        """Analyze task timing configuration"""
        print("Analyzing task configuration...")

        task_config_file = self.project_root / 'config' / 'task_config.h'
        if not task_config_file.exists():
            print("Task configuration file not found")
            return

        with open(task_config_file, 'r') as f:
            content = f.read()

        # Parse task priorities and periods
        task_pattern = re.compile(
            r'\{"([^"]+)",\s*(\d+),\s*(\d+),\s*(\d+),\s*(\d+),\s*(true|false),\s*(true|false)\}'
        )

        print("\nTask Configuration:")
        print("-" * 80)
        print(f"{'Task Name':25s} {'Priority':>8s} {'Period':>8s} {'Deadline':>8s}")
        print("-" * 80)

        for match in task_pattern.finditer(content):
            task_name = match.group(1)
            priority = int(match.group(2))
            period = int(match.group(3))
            deadline = int(match.group(5))

            self.tasks[task_name] = {
                'priority': priority,
                'period': period,
                'deadline': deadline
            }

            print(f"{task_name:25s} {priority:8d} {period:8d} {deadline:8d}")

        print("-" * 80)

    def analyze_schedulability(self):
        """Analyze task schedulability"""
        print("\nSchedulability Analysis:")
        print("-" * 60)

        # Calculate CPU utilization
        total_utilization = 0
        for task_name, config in self.tasks.items():
            if config['period'] > 0:
                utilization = config['deadline'] / config['period']
                total_utilization += utilization

                print(f"{task_name:25s} {utilization*100:6.2f}%")

        print("-" * 60)
        print(f"Total CPU Utilization: {total_utilization*100:.2f}%")

        # Check schedulability
        if total_utilization < 0.69:  # Liu & Layland bound for RM
            print("✓ System is schedulable (Rate Monotonic)")
        else:
            print("⚠ System may not be schedulable")
            self.violations.append("High CPU utilization")

    def analyze_timing_logs(self, log_file):
        """Analyze timing logs"""
        if not os.path.exists(log_file):
            print(f"Timing log not found: {log_file}")
            return

        print(f"\nAnalyzing timing log: {log_file}")

        with open(log_file, 'r') as f:
            for line in f:
                # Parse timing data
                match = re.match(
                    r'\[(\d+)\]\s+(\w+):\s+start=(\d+)\s+end=(\d+)\s+duration=(\d+)'
                , line)

                if match:
                    timestamp = int(match.group(1))
                    task_name = match.group(2)
                    duration = int(match.group(5))

                    self.timing_data[task_name].append({
                        'timestamp': timestamp,
                        'duration': duration
                    })

        # Calculate statistics
        print("\nTiming Statistics:")
        print("-" * 80)
        print(f"{'Task Name':25s} {'Count':>6s} {'Min':>8s} {'Max':>8s} {'Avg':>8s} {'Jitter':>8s}")
        print("-" * 80)

        for task_name, measurements in self.timing_data.items():
            if measurements:
                durations = [m['duration'] for m in measurements]
                count = len(durations)
                min_duration = min(durations)
                max_duration = max(durations)
                avg_duration = sum(durations) / count
                jitter = max_duration - min_duration

                print(f"{task_name:25s} {count:6d} {min_duration:8d} "
                      f"{max_duration:8d} {avg_duration:8.1f} {jitter:8d}")

                # Check for violations
                if task_name in self.tasks:
                    deadline = self.tasks[task_name]['deadline']
                    if max_duration > deadline:
                        self.violations.append(
                            f"{task_name} exceeds deadline: {max_duration} > {deadline}"
                        )

    def analyze_interrupt_timing(self):
        """Analyze interrupt timing"""
        print("\nInterrupt Timing Analysis:")
        print("-" * 40)

        # Common interrupt latencies
        interrupts = {
            'SysTick': {'priority': 15, 'typical_latency': 1},
            'CAN': {'priority': 5, 'typical_latency': 2},
            'UART': {'priority': 6, 'typical_latency': 1},
            'SPI': {'priority': 7, 'typical_latency': 1},
            'I2C': {'priority': 7, 'typical_latency': 2},
            'ADC': {'priority': 8, 'typical_latency': 3},
            'Timer': {'priority': 8, 'typical_latency': 1},
        }

        for irq_name, config in interrupts.items():
            print(f"{irq_name:15s} Priority: {config['priority']:2d} "
                  f"Latency: {config['typical_latency']}ms")

    def generate_report(self, output_file):
        """Generate timing analysis report"""
        print(f"\nGenerating report: {output_file}")

        with open(output_file, 'w') as f:
            f.write("=" * 80 + "\n")
            f.write("Timing Analysis Report\n")
            f.write("=" * 80 + "\n\n")

            # Task configuration
            f.write("Task Configuration:\n")
            f.write("-" * 40 + "\n")
            for task_name, config in self.tasks.items():
                f.write(f"{task_name}: Priority={config['priority']}, "
                       f"Period={config['period']}ms, Deadline={config['deadline']}ms\n")

            f.write("\n")

            # Violations
            if self.violations:
                f.write("Timing Violations:\n")
                f.write("-" * 40 + "\n")
                for violation in self.violations:
                    f.write(f"✗ {violation}\n")
            else:
                f.write("No timing violations detected.\n")

    def analyze(self, timing_log=None):
        """Run complete analysis"""
        print("=" * 60)
        print("Timing Analyzer")
        print("=" * 60)

        self.analyze_task_configuration()
        self.analyze_schedulability()
        self.analyze_interrupt_timing()

        if timing_log:
            self.analyze_timing_logs(timing_log)

        # Generate report
        report_file = self.project_root / 'build' / 'timing_report.txt'
        report_file.parent.mkdir(parents=True, exist_ok=True)
        self.generate_report(report_file)

        print(f"\nReport saved to: {report_file}")

def main():
    parser = argparse.ArgumentParser(description='Timing analyzer')
    parser.add_argument('--project', default='.', help='Project root directory')
    parser.add_argument('--timing-log', help='Timing log file')

    args = parser.parse_args()

    analyzer = TimingAnalyzer(args.project)
    analyzer.analyze(args.timing_log)

if __name__ == '__main__':
    main()