"""确定性评分器。"""
from __future__ import annotations

import io
import re
import zipfile

from .models import AssertionResult, AssertionSpec, RunObservation


SUPPORTED_ASSERTIONS = {
    "run_succeeded",
    "response_nonempty",
    "response_contains",
    "response_not_contains",
    "response_regex",
    "artifact_exists",
    "artifact_min_bytes",
    "artifact_zip_valid",
    "artifact_text_contains",
    "max_cost_cny",
    "max_duration_s",
}


def validate_assertion(spec: AssertionSpec) -> None:
    if spec.type not in SUPPORTED_ASSERTIONS:
        raise ValueError(f"不支持的 assertion.type: {spec.type!r}")
    if spec.type.startswith("artifact_") and not spec.path:
        raise ValueError(f"{spec.type} 需要 path")
    if spec.type in {
        "response_contains",
        "response_not_contains",
        "response_regex",
        "artifact_text_contains",
    } and not isinstance(spec.value, str):
        raise ValueError(f"{spec.type} 需要字符串 value")
    if spec.type in {"max_cost_cny", "max_duration_s"} and spec.max_value is None:
        raise ValueError(f"{spec.type} 需要 max_value")


def _description(spec: AssertionSpec) -> str:
    if spec.description:
        return spec.description
    if spec.path:
        return f"{spec.type}: {spec.path}"
    if spec.value is not None:
        return f"{spec.type}: {spec.value}"
    if spec.max_value is not None:
        return f"{spec.type}: <= {spec.max_value}"
    return spec.type


def evaluate_assertion(
    spec: AssertionSpec, observation: RunObservation
) -> AssertionResult:
    validate_assertion(spec)
    passed = False
    detail = ""
    try:
        if spec.type == "run_succeeded":
            passed = observation.run_status == "idle" and not observation.run_error
            detail = observation.run_error or observation.run_status
        elif spec.type == "response_nonempty":
            passed = bool(observation.response.strip())
            detail = f"{len(observation.response)} chars"
        elif spec.type == "response_contains":
            passed = spec.value in observation.response
        elif spec.type == "response_not_contains":
            passed = spec.value not in observation.response
        elif spec.type == "response_regex":
            passed = re.search(spec.value, observation.response, re.MULTILINE) is not None
        elif spec.type == "artifact_exists":
            observation.artifact(spec.path)
            passed = True
        elif spec.type == "artifact_min_bytes":
            data = observation.artifact(spec.path)
            passed = len(data) >= spec.min_bytes
            detail = f"{len(data)} bytes; required >= {spec.min_bytes}"
        elif spec.type == "artifact_zip_valid":
            data = observation.artifact(spec.path)
            with zipfile.ZipFile(io.BytesIO(data)) as archive:
                bad = archive.testzip()
                passed = bad is None and bool(archive.namelist())
                detail = f"first bad member: {bad}" if bad else f"{len(archive.namelist())} members"
        elif spec.type == "artifact_text_contains":
            text = observation.artifact(spec.path).decode("utf-8")
            passed = spec.value in text
        elif spec.type == "max_cost_cny":
            assert spec.max_value is not None
            passed = observation.cost_cny <= float(spec.max_value)
            detail = f"{observation.cost_cny:.6f} CNY"
        elif spec.type == "max_duration_s":
            assert spec.max_value is not None
            passed = observation.duration_s <= float(spec.max_value)
            detail = f"{observation.duration_s:.3f}s"
    except (FileNotFoundError, UnicodeDecodeError, zipfile.BadZipFile, OSError) as exc:
        detail = f"{type(exc).__name__}: {exc}"
        passed = False
    return AssertionResult(
        type=spec.type,
        passed=passed,
        weight=spec.weight,
        description=_description(spec),
        detail=detail,
    )


def score_observation(
    specs: tuple[AssertionSpec, ...], observation: RunObservation
) -> tuple[float, list[AssertionResult]]:
    results = [evaluate_assertion(spec, observation) for spec in specs]
    denominator = sum(result.weight for result in results)
    numerator = sum(result.weight for result in results if result.passed)
    return (numerator / denominator if denominator else 0.0), results