__all__ = [
    "Benchmark",
    "Benchmarks",
    "benchmark"
]

from typing import Callable, ClassVar, overload, override


BenchmarkAsFunc = Callable[[], float]

class Benchmark:
    def __init__(
        self, 
        func: BenchmarkAsFunc, 
        *,
        name: str, 
        description: str, 
        iterations: int
    ) -> None:
        self.func = func
        self.name = name
        self.description = description
        self.iterations = iterations
        
    def __call__(self) -> float:
        return self.func()
    
    @override
    def __repr__(self) -> str:
        return f'Benchmark<{self.name=}, {self.description=}, {self.iterations=}>'
        
    @override
    def __str__(self) -> str:
        return f'Benchmark({self.name=}, {self.description=}, {self.iterations=})'
    

class Benchmarks:
    _benchmarks: ClassVar[list[Benchmark]] = []

    @overload
    @classmethod
    def register(
        cls,
        call: BenchmarkAsFunc,
        *,
        name: str = "",
        description: str = "",
        iterations: int = 100,
    ) -> BenchmarkAsFunc: ...

    @overload
    @classmethod
    def register(
        cls,
        call: None = None,
        *,
        name: str = "",
        description: str = "",
        iterations: int = 100,
    ) -> Callable[[BenchmarkAsFunc], BenchmarkAsFunc]: ...

    @classmethod
    def register(
        cls,
        call: BenchmarkAsFunc | None = None,
        *,
        name: str = "",
        description: str = "",
        iterations: int = 100,
    ) -> Callable[[BenchmarkAsFunc], BenchmarkAsFunc] | BenchmarkAsFunc:
        def decorator(func: BenchmarkAsFunc) -> BenchmarkAsFunc:
            cls._benchmarks.append(
                Benchmark(
                    func,
                    name = name or func.__name__,
                    description = description or f'description for {name or func.__name__} with {iterations} iterations',
                    iterations = iterations
                )
            )
            return func

        if call is None:
            return decorator
        else:
            return decorator(call)
            
    @classmethod
    def get_benchmarks(cls) -> list[Benchmark]:
        return cls._benchmarks
            
benchmark = Benchmarks.register