"""Utility functions for text processing and searching."""

import re

from jira_client.constants import RegexPatterns


class TextUtils:
    """Utility functions for text processing."""

    @staticmethod
    def clean_text(s: str) -> str:
        """Normalize the raw description string.

          Fixes missing spaces after punctuation, numbers and time‑zones
          Collapses duplicate whitespace
        :param s:
        :return:
        """
        s = s.replace(' ', ' ')
        # fix missing spaces after periods like "Doe.Please"
        s = re.sub(r'([a-z0-9])\.([A-Z])', r'\1. \2', s)
        # fix missing spaces after commas like "Doe,Please"
        s = re.sub(r'([a-z0-9]),([A-Z])', r'\1, \2', s)
        # fix missing spaces after numbers like "703101Title"
        s = re.sub(r'([0-9])([A-Z])', r'\1 \2', s)
        # fix missing spaces before capitalized words like "MarketingEmail"
        # or "user@example.comDepartment"
        s = re.sub(r'([a-z])([A-Z][a-z]+)', r'\1 \2', s)
        # fix missing spaces after timezone abbreviations like "UTCLitigation"
        s = re.sub(r'(UTC|PST|EST|CST|MST)([A-Z][a-z]+)', r'\1 \2', s)
        # normalize whitespace
        s = re.sub(r'\s+', ' ', s).strip()
        return s


class SearchUtils:
    """Utility functions for searching text patterns."""

    @staticmethod
    def find_all_emails(
        text: str,
    ) -> list[str]:
        """Return list of emails for all matches in the text.

        :param text:
        :return:
        """
        return [m.group(0) for m in RegexPatterns.EMAIL_RE.finditer(text)]

    @staticmethod
    def _find_iso_date_after(label: str, text: str) -> str | None:
        """Return the first ``YYYY-MM-DD`` date following *label* in *text*.

        :param label: Regex-safe label preceding the date (e.g. ``r'Last day of Employment:'``).
        :param text: Text to search.
        :return: The ISO date string, or ``None`` if not found.
        """
        match = re.search(
            label + r'\s+([0-9]{4}-[0-9]{2}-[0-9]{2})',
            text,
            re.UNICODE,
        )
        if match:
            return match.group(1)
        return None

    @staticmethod
    def find_last_working_day(text: str) -> str | None:
        """Find last working day in the text.

        example: Last day of Employment: 2026-01-30

        :param text:
        :return:
        """
        return SearchUtils._find_iso_date_after(r'Last day of Employment:', text)

    @staticmethod
    def find_suspension_start_date(text: str) -> str | None:
        """Find the suspension start date in the text.

        example: Suspension Start Date: 2026-03-16

        :param text:
        :return:
        """
        return SearchUtils._find_iso_date_after(r'Suspension Start Date:', text)

    @staticmethod
    def find_full_name(text: str, pattern: re.Pattern[str]) -> str | None:
        """Find first name and last name in the text using *pattern*.

        :param text: Text to search.
        :param pattern: Compiled regex whose first group captures the full name.
        :return: The captured full name, or ``None`` if not found.
        """
        match = pattern.search(text)
        if match:
            return match.group(1)
        return None