"""WikiLeaks-specific crawl helpers for Mosaic collectors."""
import re
import logging
from urllib.parse import urljoin
from typing import Optional

logger = logging.getLogger(__name__)


def extract_extra_links(html: str, base_url: str, source_name: str) -> list[str]:
    """Extract additional links using WikiLeaks-specific patterns.

    Different WikiLeaks collections have different page structures.
    This function handles the quirks of each.
    """
    links = []

    if source_name == 'vault7':
        links.extend(_vault7_links(html, base_url))
    elif source_name == 'vault8':
        links.extend(_vault8_links(html, base_url))
    elif source_name == 'cablegate':
        links.extend(_cablegate_links(html, base_url))
    elif source_name == 'spyfiles':
        links.extend(_spyfiles_links(html, base_url))
    elif source_name == 'emails':
        links.extend(_email_links(html, base_url))

    return links


def _vault7_links(html: str, base_url: str) -> list[str]:
    """Extract Vault 7 project page links.

    Vault 7 has a main index with project names that link to sub-pages.
    Each project page has document links.
    """
    links = []
    # Match project links like /vault7/#Dark Matter
    for match in re.finditer(r'href=["\'](/vault7/[^"\']+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    # Match document/file links
    for match in re.finditer(r'href=["\']([^"\']*(?:\.pdf|\.zip|\.tar\.gz)[^"\']*)["\']', html, re.IGNORECASE):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    return links


def _vault8_links(html: str, base_url: str) -> list[str]:
    """Extract Vault 8 source code repository links."""
    links = []
    for match in re.finditer(r'href=["\'](/vault8/[^"\']+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)
    return links


def _cablegate_links(html: str, base_url: str) -> list[str]:
    """Extract Cablegate cable links with pagination support.

    Cablegate uses /plusd/cables/ with date-based navigation.
    Individual cables are at /plusd/cables/CABLE_ID
    """
    links = []

    # Individual cable links
    for match in re.finditer(r'href=["\'](/plusd/cables/[0-9A-Z]+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    # Pagination links
    for match in re.finditer(r'href=["\'](/plusd/[^"\']*(?:page|offset|start)=[^"\']+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    # Date-based navigation
    for match in re.finditer(r'href=["\'](/plusd/cables/\?[^"\']+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    return links


def _spyfiles_links(html: str, base_url: str) -> list[str]:
    """Extract Spy Files document links."""
    links = []
    for match in re.finditer(r'href=["\'](/spyfiles/[^"\']+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)
    return links


def _email_links(html: str, base_url: str) -> list[str]:
    """Extract email dump links with ID-based navigation."""
    links = []

    # Email ID links
    for match in re.finditer(r'href=["\']([^"\']*emailid/\d+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    # Pagination
    for match in re.finditer(r'href=["\']([^"\']*(?:page|offset)=\d+)["\']', html):
        link = urljoin(base_url, match.group(1))
        links.append(link)

    return links


def parse_cable_date(cable_id: str) -> Optional[str]:
    """Extract date from cable ID format.

    Cable IDs often start with a two-digit year and month:
    e.g., 07PARIS1234 → 2007 (approximate)
    """
    match = re.match(r'^(\d{2})[A-Z]', cable_id)
    if match:
        year = int(match.group(1))
        # WikiLeaks cables span roughly 1966-2010
        if year >= 66:
            return f"19{year:02d}"
        else:
            return f"20{year:02d}"
    return None


def detect_wikileaks_source(url: str) -> Optional[str]:
    """Detect which WikiLeaks collection a URL belongs to."""
    if '/vault7/' in url:
        return 'vault7'
    elif '/vault8/' in url:
        return 'vault8'
    elif '/plusd/' in url or '/cablegate/' in url:
        return 'cablegate'
    elif '/spyfiles/' in url:
        return 'spyfiles'
    elif 'emailid/' in url or '/dnc-emails/' in url or '/podesta-emails/' in url:
        return 'emails'
    return None