#!/usr/bin/env python3
"""
速度测试脚本 - 对比 PyTorch vs TensorRT 推理性能
测试 DeCLIP (csa模式) 和 CLIP (vanilla模式) 的延迟和吞吐量

Usage:
    python benchmark_speed.py --pytorch-model <path> --trt-engine <path>
    python benchmark_speed.py --all  # 运行所有配置的测试
"""

import os
import sys
import argparse
import time
import json
from pathlib import Path
from dataclasses import dataclass, asdict
from typing import Optional, List, Dict, Any
from datetime import datetime

import torch
import torch.cuda
import numpy as np

# 添加项目根目录到路径
SCRIPT_DIR = Path(__file__).parent
DECLIP_ROOT = SCRIPT_DIR.parent
sys.path.insert(0, str(DECLIP_ROOT))
sys.path.insert(0, str(DECLIP_ROOT / 'src'))


@dataclass
class BenchmarkResult:
    """Benchmark 结果"""
    model_name: str
    mode: str  # vanilla or csa
    backend: str  # pytorch, onnx, tensorrt
    precision: str  # fp32, fp16, int8
    image_size: tuple
    batch_size: int
    warmup_rounds: int
    test_rounds: int
    latency_mean_ms: float
    latency_std_ms: float
    latency_min_ms: float
    latency_max_ms: float
    throughput_fps: float
    memory_mb: float
    timestamp: str


class PyTorchBenchmark:
    """PyTorch 模型 benchmark"""
    
    def __init__(self, model, device='cuda:0', mode='csa'):
        self.model = model
        self.device = torch.device(device)
        self.mode = mode
        self.model.to(self.device)
        self.model.eval()
    
    @torch.no_grad()
    def run(self, input_tensor: torch.Tensor) -> torch.Tensor:
        """运行单次推理"""
        if hasattr(self.model, 'visual'):
            return self.model.visual.encode_dense(
                input_tensor, keep_shape=True, mode=self.mode
            )
        else:
            return self.model.encode_dense(
                input_tensor, keep_shape=True, mode=self.mode
            )
    
    def benchmark(
        self, 
        image_size: tuple = (560, 560),
        batch_size: int = 1,
        warmup: int = 10,
        iterations: int = 100,
        fp16: bool = False
    ) -> BenchmarkResult:
        """运行 benchmark"""
        H, W = image_size
        dtype = torch.float16 if fp16 else torch.float32
        
        # 创建输入
        input_tensor = torch.randn(
            batch_size, 3, H, W,
            device=self.device,
            dtype=dtype
        )
        
        if fp16:
            self.model.half()
        
        # Warmup
        for _ in range(warmup):
            _ = self.run(input_tensor)
            torch.cuda.synchronize()
        
        # 测试
        latencies = []
        torch.cuda.reset_peak_memory_stats()
        
        for _ in range(iterations):
            torch.cuda.synchronize()
            start = time.perf_counter()
            
            _ = self.run(input_tensor)
            
            torch.cuda.synchronize()
            end = time.perf_counter()
            
            latencies.append((end - start) * 1000)  # ms
        
        memory_mb = torch.cuda.max_memory_allocated() / (1024 * 1024)
        
        latencies = np.array(latencies)
        
        return BenchmarkResult(
            model_name=type(self.model).__name__,
            mode=self.mode,
            backend='pytorch',
            precision='fp16' if fp16 else 'fp32',
            image_size=image_size,
            batch_size=batch_size,
            warmup_rounds=warmup,
            test_rounds=iterations,
            latency_mean_ms=float(latencies.mean()),
            latency_std_ms=float(latencies.std()),
            latency_min_ms=float(latencies.min()),
            latency_max_ms=float(latencies.max()),
            throughput_fps=float(batch_size * 1000 / latencies.mean()),
            memory_mb=float(memory_mb),
            timestamp=datetime.now().isoformat()
        )


class TensorRTBenchmark:
    """TensorRT 引擎 benchmark"""
    
    def __init__(self, engine_path: str, device='cuda:0'):
        self.engine_path = engine_path
        self.device = device
        self.engine = None
        self.context = None
        self.stream = None
        
        self._load_engine()
    
    def _load_engine(self):
        """加载 TRT 引擎"""
        try:
            import tensorrt as trt
            import pycuda.driver as cuda
            import pycuda.autoinit
            
            self.cuda = cuda
            self.trt = trt
            
            logger = trt.Logger(trt.Logger.WARNING)
            runtime = trt.Runtime(logger)
            
            with open(self.engine_path, 'rb') as f:
                self.engine = runtime.deserialize_cuda_engine(f.read())
            
            self.context = self.engine.create_execution_context()
            self.stream = cuda.Stream()
            
            # 获取输入输出信息
            self.input_name = self.engine.get_tensor_name(0)
            self.output_name = self.engine.get_tensor_name(1)
            
        except ImportError as e:
            raise ImportError(f"TensorRT/PyCUDA not installed: {e}")
    
    def run(self, input_np: np.ndarray) -> np.ndarray:
        """运行单次推理"""
        cuda = self.cuda
        
        # 设置输入形状
        self.context.set_input_shape(self.input_name, input_np.shape)
        
        # 获取输出形状
        output_shape = self.context.get_tensor_shape(self.output_name)
        output_np = np.empty(output_shape, dtype=np.float32)
        
        # 分配 GPU 内存
        d_input = cuda.mem_alloc(input_np.nbytes)
        d_output = cuda.mem_alloc(output_np.nbytes)
        
        # 复制输入
        cuda.memcpy_htod_async(d_input, input_np.astype(np.float32), self.stream)
        
        # 设置绑定
        self.context.set_tensor_address(self.input_name, int(d_input))
        self.context.set_tensor_address(self.output_name, int(d_output))
        
        # 推理
        self.context.execute_async_v3(self.stream.handle)
        
        # 复制输出
        cuda.memcpy_dtoh_async(output_np, d_output, self.stream)
        self.stream.synchronize()
        
        return output_np
    
    def benchmark(
        self,
        image_size: tuple = (560, 560),
        batch_size: int = 1,
        warmup: int = 10,
        iterations: int = 100
    ) -> BenchmarkResult:
        """运行 benchmark"""
        cuda = self.cuda
        H, W = image_size
        
        # 创建输入
        input_np = np.random.randn(batch_size, 3, H, W).astype(np.float32)
        
        # 设置输入形状
        self.context.set_input_shape(self.input_name, input_np.shape)
        output_shape = self.context.get_tensor_shape(self.output_name)
        output_np = np.empty(output_shape, dtype=np.float32)
        
        # 预分配 GPU 内存
        d_input = cuda.mem_alloc(input_np.nbytes)
        d_output = cuda.mem_alloc(output_np.nbytes)
        
        # Warmup
        for _ in range(warmup):
            cuda.memcpy_htod(d_input, input_np)
            self.context.set_tensor_address(self.input_name, int(d_input))
            self.context.set_tensor_address(self.output_name, int(d_output))
            self.context.execute_async_v3(self.stream.handle)
            self.stream.synchronize()
        
        # 测试
        latencies = []
        
        for _ in range(iterations):
            cuda.memcpy_htod(d_input, input_np)
            
            start = time.perf_counter()
            
            self.context.set_tensor_address(self.input_name, int(d_input))
            self.context.set_tensor_address(self.output_name, int(d_output))
            self.context.execute_async_v3(self.stream.handle)
            self.stream.synchronize()
            
            end = time.perf_counter()
            
            latencies.append((end - start) * 1000)  # ms
        
        latencies = np.array(latencies)
        
        # 从引擎路径解析精度
        precision = 'fp16' if 'fp16' in self.engine_path else 'fp32'
        if 'int8' in self.engine_path:
            precision = 'int8'
        
        return BenchmarkResult(
            model_name=Path(self.engine_path).stem,
            mode='unknown',  # 从文件名解析
            backend='tensorrt',
            precision=precision,
            image_size=image_size,
            batch_size=batch_size,
            warmup_rounds=warmup,
            test_rounds=iterations,
            latency_mean_ms=float(latencies.mean()),
            latency_std_ms=float(latencies.std()),
            latency_min_ms=float(latencies.min()),
            latency_max_ms=float(latencies.max()),
            throughput_fps=float(batch_size * 1000 / latencies.mean()),
            memory_mb=0.0,  # TRT 内存统计需要额外处理
            timestamp=datetime.now().isoformat()
        )


class ONNXBenchmark:
    """ONNX Runtime benchmark"""
    
    def __init__(self, onnx_path: str, device='cuda'):
        self.onnx_path = onnx_path
        self.device = device
        
        import onnxruntime as ort
        
        providers = ['CUDAExecutionProvider'] if device == 'cuda' else ['CPUExecutionProvider']
        self.session = ort.InferenceSession(onnx_path, providers=providers)
        self.input_name = self.session.get_inputs()[0].name
    
    def run(self, input_np: np.ndarray) -> np.ndarray:
        """运行单次推理"""
        return self.session.run(None, {self.input_name: input_np})[0]
    
    def benchmark(
        self,
        image_size: tuple = (560, 560),
        batch_size: int = 1,
        warmup: int = 10,
        iterations: int = 100
    ) -> BenchmarkResult:
        """运行 benchmark"""
        H, W = image_size
        input_np = np.random.randn(batch_size, 3, H, W).astype(np.float32)
        
        # Warmup
        for _ in range(warmup):
            _ = self.run(input_np)
        
        # 测试
        latencies = []
        
        for _ in range(iterations):
            start = time.perf_counter()
            _ = self.run(input_np)
            end = time.perf_counter()
            latencies.append((end - start) * 1000)
        
        latencies = np.array(latencies)
        
        return BenchmarkResult(
            model_name=Path(self.onnx_path).stem,
            mode='unknown',
            backend='onnxruntime',
            precision='fp32',
            image_size=image_size,
            batch_size=batch_size,
            warmup_rounds=warmup,
            test_rounds=iterations,
            latency_mean_ms=float(latencies.mean()),
            latency_std_ms=float(latencies.std()),
            latency_min_ms=float(latencies.min()),
            latency_max_ms=float(latencies.max()),
            throughput_fps=float(batch_size * 1000 / latencies.mean()),
            memory_mb=0.0,
            timestamp=datetime.now().isoformat()
        )


def print_result(result: BenchmarkResult):
    """打印 benchmark 结果"""
    print(f"\n{'='*60}")
    print(f"Benchmark Results: {result.model_name}")
    print(f"{'='*60}")
    print(f"Backend:        {result.backend}")
    print(f"Mode:           {result.mode}")
    print(f"Precision:      {result.precision}")
    print(f"Image Size:     {result.image_size}")
    print(f"Batch Size:     {result.batch_size}")
    print(f"Warmup:         {result.warmup_rounds} rounds")
    print(f"Test:           {result.test_rounds} rounds")
    print(f"-" * 40)
    print(f"Latency Mean:   {result.latency_mean_ms:.2f} ms")
    print(f"Latency Std:    {result.latency_std_ms:.2f} ms")
    print(f"Latency Min:    {result.latency_min_ms:.2f} ms")
    print(f"Latency Max:    {result.latency_max_ms:.2f} ms")
    print(f"Throughput:     {result.throughput_fps:.1f} FPS")
    if result.memory_mb > 0:
        print(f"GPU Memory:     {result.memory_mb:.1f} MB")
    print(f"{'='*60}")


def compare_results(results: List[BenchmarkResult]):
    """对比多个结果"""
    if len(results) < 2:
        return
    
    print(f"\n{'='*60}")
    print("Comparison Summary")
    print(f"{'='*60}")
    
    # 按 backend 排序
    results = sorted(results, key=lambda x: (x.mode, x.backend))
    
    # 打印表格头
    headers = ["Model", "Mode", "Backend", "Precision", "Latency (ms)", "FPS", "Speedup"]
    row_format = "{:<20} {:<8} {:<12} {:<10} {:>12} {:>8} {:>8}"
    print(row_format.format(*headers))
    print("-" * 80)
    
    # 基准 (第一个 PyTorch 结果)
    baseline = next((r for r in results if r.backend == 'pytorch'), results[0])
    
    for result in results:
        speedup = baseline.latency_mean_ms / result.latency_mean_ms
        speedup_str = f"{speedup:.2f}x" if speedup != 1.0 else "-"
        
        print(row_format.format(
            result.model_name[:20],
            result.mode,
            result.backend,
            result.precision,
            f"{result.latency_mean_ms:.2f}",
            f"{result.throughput_fps:.1f}",
            speedup_str
        ))


def save_results(results: List[BenchmarkResult], output_path: str):
    """保存结果到 JSON"""
    data = [asdict(r) for r in results]
    
    with open(output_path, 'w') as f:
        json.dump(data, f, indent=2)
    
    print(f"\nResults saved to: {output_path}")


def parse_args():
    parser = argparse.ArgumentParser(description='速度测试')
    
    parser.add_argument('--pytorch-model', type=str,
                        help='PyTorch 模型检查点路径')
    parser.add_argument('--trt-engine', type=str,
                        help='TensorRT 引擎路径')
    parser.add_argument('--onnx-model', type=str,
                        help='ONNX 模型路径')
    
    parser.add_argument('--model-name', type=str, default='EVA02-CLIP-B-16',
                        help='模型名称')
    parser.add_argument('--mode', type=str, default='csa',
                        choices=['vanilla', 'csa'],
                        help='特征模式')
    
    parser.add_argument('--image-size', type=int, nargs=2, default=[560, 560],
                        help='图像尺寸 [H, W]')
    parser.add_argument('--batch-size', type=int, default=1,
                        help='批处理大小')
    parser.add_argument('--warmup', type=int, default=10,
                        help='预热轮数')
    parser.add_argument('--iterations', type=int, default=100,
                        help='测试轮数')
    
    parser.add_argument('--fp16', action='store_true',
                        help='使用 FP16 (仅 PyTorch)')
    
    parser.add_argument('--all', action='store_true',
                        help='运行所有配置的测试')
    parser.add_argument('--output', type=str, default='results/benchmark_results.json',
                        help='输出文件路径')
    
    parser.add_argument('--device', type=str, default='cuda:0',
                        help='设备')
    
    return parser.parse_args()


def run_all_benchmarks(args):
    """运行所有配置的测试"""
    from configs.fvit_tensorrt_fp16 import model_paths, benchmark_config
    
    results = []
    
    # 测试配置
    modes = ['vanilla', 'csa']
    image_sizes = benchmark_config['input_sizes']
    batch_sizes = benchmark_config['batch_sizes']
    
    # 检查引擎目录
    engine_dir = SCRIPT_DIR / 'engines'
    
    for mode in modes:
        model_type = 'clip' if mode == 'vanilla' else 'declip'
        
        # 查找对应的引擎
        engine_pattern = f"{model_type}_{mode}_*_fp16.engine"
        engines = list(engine_dir.glob(engine_pattern))
        
        if not engines:
            print(f"Warning: No TRT engine found for {model_type} {mode}")
            continue
        
        engine_path = engines[0]
        
        for image_size in image_sizes:
            for batch_size in batch_sizes:
                # TensorRT benchmark
                try:
                    benchmark = TensorRTBenchmark(str(engine_path), args.device)
                    result = benchmark.benchmark(
                        image_size=image_size,
                        batch_size=batch_size,
                        warmup=args.warmup,
                        iterations=args.iterations
                    )
                    result.mode = mode
                    results.append(result)
                    print_result(result)
                except Exception as e:
                    print(f"Error benchmarking TRT {mode}: {e}")
    
    return results


def main():
    args = parse_args()
    
    results = []
    
    print(f"\n{'='*60}")
    print("DeCLIP/CLIP Speed Benchmark")
    print(f"{'='*60}")
    print(f"Device: {args.device}")
    print(f"Image Size: {args.image_size}")
    print(f"Batch Size: {args.batch_size}")
    print(f"Warmup: {args.warmup}")
    print(f"Iterations: {args.iterations}")
    
    if args.all:
        results = run_all_benchmarks(args)
    else:
        image_size = tuple(args.image_size)
        
        # PyTorch benchmark
        if args.pytorch_model:
            from open_clip import create_model
            
            print(f"\nLoading PyTorch model: {args.pytorch_model}")
            model = create_model(
                args.model_name,
                pretrained='eva',
                device=args.device,
                precision='fp32',
                output_dict=True,
                cache_dir=args.pytorch_model
            )
            
            benchmark = PyTorchBenchmark(model, args.device, args.mode)
            result = benchmark.benchmark(
                image_size=image_size,
                batch_size=args.batch_size,
                warmup=args.warmup,
                iterations=args.iterations,
                fp16=args.fp16
            )
            results.append(result)
            print_result(result)
        
        # ONNX benchmark
        if args.onnx_model:
            print(f"\nLoading ONNX model: {args.onnx_model}")
            benchmark = ONNXBenchmark(args.onnx_model, 'cuda')
            result = benchmark.benchmark(
                image_size=image_size,
                batch_size=args.batch_size,
                warmup=args.warmup,
                iterations=args.iterations
            )
            result.mode = args.mode
            results.append(result)
            print_result(result)
        
        # TensorRT benchmark
        if args.trt_engine:
            print(f"\nLoading TensorRT engine: {args.trt_engine}")
            benchmark = TensorRTBenchmark(args.trt_engine, args.device)
            result = benchmark.benchmark(
                image_size=image_size,
                batch_size=args.batch_size,
                warmup=args.warmup,
                iterations=args.iterations
            )
            result.mode = args.mode
            results.append(result)
            print_result(result)
    
    # 对比结果
    if len(results) > 1:
        compare_results(results)
    
    # 保存结果
    if results:
        output_path = Path(args.output)
        output_path.parent.mkdir(parents=True, exist_ok=True)
        save_results(results, str(output_path))


if __name__ == '__main__':
    main()