import re
from typing import Any, Dict, List


USERNAME_PATTERN = re.compile(r"@([A-Za-z0-9_]{3,})")
TME_PATTERN = re.compile(r"(?:https?://)?t\.me/([A-Za-z0-9_]{3,})")
ID_PATTERN = re.compile(r"`(\d{4,})`")


def extract_entities(text: str) -> List[Dict[str, Any]]:
    if not text:
        return []

    entities: List[Dict[str, Any]] = []
    seen = set()

    for user_id in set(ID_PATTERN.findall(text)):
        key = ("user_id", user_id)
        if key not in seen:
            seen.add(key)
            entities.append({
                "type": "user_id",
                "value": user_id
            })

    for username in set(USERNAME_PATTERN.findall(text)):
        normalized = username.strip()
        if not normalized:
            continue
        key = ("username", normalized.lower())
        if key not in seen:
            seen.add(key)
            entities.append({
                "type": "username",
                "value": normalized.lower(),
                "display": normalized
            })

    for link in set(TME_PATTERN.findall(text)):
        normalized = f"t.me/{link}"
        key = ("tme_link", normalized.lower())
        if key not in seen:
            seen.add(key)
            entities.append({
                "type": "tme_link",
                "value": normalized.lower(),
                "display": normalized
            })

    return entities