#!/usr/bin/env python3
"""算法测量结果契约 1.0 的零第三方依赖校验器。"""

from __future__ import annotations

import json
import math
import re
import sys
from pathlib import Path
from typing import Any


METRIC_CODE_RE = re.compile(r"^[a-z0-9]+(?:[._-][a-z0-9]+)*$")
TASK_NO_RE = re.compile(r"^[A-Za-z0-9][A-Za-z0-9._-]*$")
TASK_NAME_PREFIX_RE = re.compile(r"^任务\s*\d+")
FINAL_STATUSES = {"pass", "warning", "fail"}


def is_number(value: Any) -> bool:
    return isinstance(value, (int, float)) and not isinstance(value, bool) and math.isfinite(value)


def validate(payload: Any) -> list[str]:
    errors: list[str] = []
    if not isinstance(payload, dict):
        return ["根节点必须是 JSON 对象"]

    if not isinstance(payload.get("schemaVersion"), int) or payload["schemaVersion"] < 1:
        errors.append("schemaVersion 必须是大于等于 1 的整数")
    if payload.get("measurementContractVersion") != "1.0":
        errors.append('measurementContractVersion 必须为 "1.0"')
    if payload.get("status") not in {"completed", "error"}:
        errors.append("status 必须为 completed 或 error")

    measurements = payload.get("measurements")
    if payload.get("status") == "completed" and not isinstance(measurements, list):
        errors.append("completed 结果必须包含 measurements 数组")
        measurements = []
    elif measurements is None:
        measurements = []
    elif not isinstance(measurements, list):
        errors.append("measurements 必须是数组")
        measurements = []

    unique_keys: set[tuple[str, str, str]] = set()
    for index, item in enumerate(measurements):
        path = f"measurements[{index}]"
        if not isinstance(item, dict):
            errors.append(f"{path} 必须是对象")
            continue

        task_no = item.get("taskNo")
        metric_code = item.get("metricCode")
        name = item.get("name")
        position = item.get("position", "")
        value = item.get("value", ...)
        status = item.get("status")

        if not isinstance(task_no, str) or not TASK_NO_RE.fullmatch(task_no):
            errors.append(f"{path}.taskNo 必须是非空规范字符串，数字任务号也要加引号")
        if not isinstance(metric_code, str) or not METRIC_CODE_RE.fullmatch(metric_code):
            errors.append(f"{path}.metricCode 格式无效")
        if not isinstance(name, str) or not name.strip():
            errors.append(f"{path}.name 必须是非空字符串")
        elif TASK_NAME_PREFIX_RE.search(name):
            errors.append(f"{path}.name 不得包含任务号前缀，请使用 taskNo 字段")
        if position and not isinstance(position, str):
            errors.append(f"{path}.position 必须是字符串")
        if value is ... or (value is not None and not is_number(value)):
            errors.append(f"{path}.value 必须是有限数值或 null")
        if status not in FINAL_STATUSES:
            errors.append(f"{path}.status 必须为 pass、warning 或 fail，正式结果不得使用 info")
        if value is None and status == "pass":
            errors.append(f"{path} 的 value 为 null 时不能判定为 pass")
        if "baseline" in item and (not is_number(item["baseline"]) or item["baseline"] <= 0):
            errors.append(f"{path}.baseline 必须是正数")
        if "tolerance" in item and (not is_number(item["tolerance"]) or item["tolerance"] < 0):
            errors.append(f"{path}.tolerance 必须是非负有限数值")

        if isinstance(task_no, str) and isinstance(metric_code, str) and isinstance(position, str):
            key = (task_no, metric_code, position)
            if key in unique_keys:
                errors.append(f"{path} 与其他正式测量项重复：taskNo + metricCode + position 必须唯一")
            unique_keys.add(key)

    extra = payload.get("extra", {})
    if extra is not None and not isinstance(extra, dict):
        errors.append("extra 必须是对象")
        extra = {}
    intermediate = extra.get("intermediateMetrics", []) if isinstance(extra, dict) else []
    if not isinstance(intermediate, list):
        errors.append("extra.intermediateMetrics 必须是数组")
        intermediate = []
    for index, item in enumerate(intermediate):
        path = f"extra.intermediateMetrics[{index}]"
        if not isinstance(item, dict):
            errors.append(f"{path} 必须是对象")
            continue
        if any(field in item for field in ("taskNo", "status", "tolerance")):
            errors.append(f"{path} 不得包含 taskNo、status 或 tolerance")
        code = item.get("metricCode")
        if not isinstance(code, str) or not METRIC_CODE_RE.fullmatch(code):
            errors.append(f"{path}.metricCode 格式无效")
        if not isinstance(item.get("name"), str) or not item["name"].strip():
            errors.append(f"{path}.name 必须是非空字符串")
        value = item.get("value", ...)
        if value is ... or (value is not None and not is_number(value)):
            errors.append(f"{path}.value 必须是有限数值或 null")

    return errors


def main() -> int:
    if len(sys.argv) != 2:
        print(f"用法: {Path(sys.argv[0]).name} /path/to/result.json", file=sys.stderr)
        return 2
    path = Path(sys.argv[1])
    try:
        payload = json.loads(path.read_text(encoding="utf-8"), parse_constant=lambda value: (_ for _ in ()).throw(ValueError(f"非法数值 {value}")))
    except (OSError, json.JSONDecodeError, ValueError) as exc:
        print(f"校验失败: 无法读取标准 JSON：{exc}", file=sys.stderr)
        return 1

    errors = validate(payload)
    if errors:
        print(f"校验失败，共 {len(errors)} 个问题：", file=sys.stderr)
        for error in errors:
            print(f"- {error}", file=sys.stderr)
        return 1
    print(f"校验通过：{path}")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())