"""
Agregator — przetwarza eventy GitLab na statystyki per użytkownik.
"""

from collections import defaultdict
from dataclasses import dataclass, field


@dataclass
class UserStats:
    name: str = ""
    username: str = ""
    user_id: int = 0
    commits: int = 0
    merge_requests: int = 0
    comments: int = 0
    other: int = 0

    @property
    def total_contributions(self) -> int:
        return self.commits + self.merge_requests + self.comments + self.other


class Aggregator:
    def __init__(self):
        self._stats: dict[int, UserStats] = defaultdict(UserStats)

    def process_events(self, events: list[dict]) -> None:
        """
        Przetwarza listę eventów GitLab i agreguje statystyki.

        Typy akcji:
          - pushed       → commit
          - merged       → merge request
          - commented    → komentarz
          - created/closed/reopened → inne
        """
        for event in events:
            author = event.get("author") or {}
            uid = author.get("id") or event.get("author_id")
            if not uid:
                continue

            stats = self._stats[uid]
            stats.user_id = uid
            stats.name = author.get("name", stats.name)
            stats.username = author.get("username", stats.username)

            action = event.get("action_name", "")

            if action == "pushed to" or action == "pushed new":
                # Liczymy commity z push events
                push_data = event.get("push_data") or {}
                commit_count = push_data.get("commit_count", 1)
                stats.commits += max(commit_count, 1)
            elif action in ("accepted", "merged"):
                stats.merge_requests += 1
            elif action == "commented on":
                stats.comments += 1
            else:
                stats.other += 1

    def get_stats(self) -> list[UserStats]:
        """Zwraca listę statystyk posortowaną malejąco po contributions."""
        return sorted(
            self._stats.values(),
            key=lambda s: s.total_contributions,
            reverse=True,
        )