from __future__ import annotations

import re
from typing import Any

_EMAIL_RE = re.compile(r"^[^@\s]+@[^@\s]+\.[^@\s]+$")


def strict_phone(value: str) -> bool:
    return (
        len(value) == 11
        and value.isascii()
        and value.isdigit()
        and value[0] == "1"
        and value[1] in "3456789"
    )


def mask_phone(value: Any) -> str | None:
    if not isinstance(value, str) or len(value) != 11:
        return None
    return f"{value[:3]}****{value[-4:]}"


def valid_month(value: Any) -> bool:
    if not isinstance(value, str) or len(value) != 7 or value[4] != "-":
        return False
    year, month = value.split("-", 1)
    return (
        year.isdigit()
        and month.isdigit()
        and 1900 <= int(year) <= 2100
        and 1 <= int(month) <= 12
    )


def anchor_missing_fields(
    profile: dict[str, Any], required: list[str]
) -> list[str]:
    anchor = profile.get("anchor", {})
    missing = [field for field in required if not _present(anchor.get(field))]
    start = anchor.get("start_date")
    end = anchor.get("end_date_or_present")
    if start and not valid_month(start) and "start_date" not in missing:
        missing.append("start_date")
    if end and end != "present" and not valid_month(end) and "end_date_or_present" not in missing:
        missing.append("end_date_or_present")
    if valid_month(start) and valid_month(end) and end < start and "end_date_or_present" not in missing:
        missing.append("end_date_or_present")
    return missing


def can_create_resume(profile: dict[str, Any], missing: list[str]) -> bool:
    base_ready = bool(
        profile.get("privacy_accepted")
        and strict_phone(str(profile.get("phone") or ""))
        and str(profile.get("name") or "").strip()
        and profile.get("job_type") in {"campus", "social", "internship"}
    )
    return base_ready and not missing
def _present(value: Any) -> bool:
    return bool(value.strip()) if isinstance(value, str) else value is not None


def valid_email(value: Any) -> bool:
    return isinstance(value, str) and bool(_EMAIL_RE.match(value))


def valid_url(value: Any) -> bool:
    if not isinstance(value, str):
        return False
    return value.startswith(("https://", "http://")) and len(value) > 8


def normalize_tags(values: Any, *, max_items: int = 20, max_length: int = 32) -> list[str]:
    """标签规范化：去空白、去空、去重（大小写不敏感保留首个写法）、限长限量。"""
    if not isinstance(values, list):
        return []
    seen: set[str] = set()
    result: list[str] = []
    for value in values:
        if not isinstance(value, str):
            continue
        item = value.strip()
        if not item or len(item) > max_length:
            continue
        key = item.casefold()
        if key in seen:
            continue
        seen.add(key)
        result.append(item)
        if len(result) >= max_items:
            break
    return result


def competition_entry_errors(entry: dict[str, Any]) -> list[str]:
    """竞赛条目核心字段校验，返回问题字段名列表（空 = 合法）。"""
    errors: list[str] = []
    if not str(entry.get("name") or "").strip():
        errors.append("name")
    if not str(entry.get("award") or "").strip():
        errors.append("award")
    if not valid_month(entry.get("date")):
        errors.append("date")
    return errors


def record_entry_errors(entry: dict[str, Any], required: list[str] | tuple[str, ...]) -> list[str]:
    """经历卡片核心字段校验：非空 + YYYY-MM/present + 结束不早于开始。"""
    errors = [field for field in required if not str(entry.get(field) or "").strip()]
    start = str(entry.get("start_date") or "")
    end = str(entry.get("end_date_or_present") or "")
    if start and not valid_month(start) and "start_date" not in errors:
        errors.append("start_date")
    if end and end != "present" and not valid_month(end) and "end_date_or_present" not in errors:
        errors.append("end_date_or_present")
    if valid_month(start) and valid_month(end) and end < start and "end_date_or_present" not in errors:
        errors.append("end_date_or_present")
    return errors