"""
Hugging Face Hub Contributions Fetcher

Fetches contribution data (commits) from a user's models, datasets, and spaces
using the Hugging Face Hub API.
"""

from huggingface_hub import HfApi
from collections import defaultdict
from datetime import datetime, timedelta
from typing import Optional
from dataclasses import dataclass
import logging

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)


@dataclass
class ContributionStats:
    """Statistics about a user's contributions."""
    total_commits: int
    total_repos: int
    models_count: int
    datasets_count: int
    spaces_count: int
    longest_streak: int
    current_streak: int
    most_active_day: Optional[str]
    most_active_count: int
    contributions_by_date: dict[str, int]
    contributions_by_repo: dict[str, list[dict]]


def get_date_range(days: int = 365) -> list[str]:
    """Generate a list of date strings for the past N days."""
    today = datetime.now().date()
    return [
        (today - timedelta(days=i)).strftime("%Y-%m-%d")
        for i in range(days - 1, -1, -1)
    ]


def calculate_streaks(contributions: dict[str, int], days: int = 365) -> tuple[int, int]:
    """Calculate longest and current contribution streaks."""
    dates = get_date_range(days)

    longest_streak = 0
    current_streak = 0
    temp_streak = 0

    for date in dates:
        if contributions.get(date, 0) > 0:
            temp_streak += 1
            longest_streak = max(longest_streak, temp_streak)
        else:
            temp_streak = 0

    # Calculate current streak (from today backwards)
    for date in reversed(dates):
        if contributions.get(date, 0) > 0:
            current_streak += 1
        else:
            break

    return longest_streak, current_streak


def fetch_user_contributions(
    username: str,
    token: Optional[str] = None,
    days: int = 365,
    progress_callback=None
) -> ContributionStats:
    """
    Fetch all contributions for a Hugging Face user.

    Args:
        username: The HF username to fetch contributions for
        token: Optional HF token for accessing private repos
        days: Number of days to look back (default 365)
        progress_callback: Optional callback for progress updates

    Returns:
        ContributionStats object with all contribution data
    """
    api = HfApi(token=token)
    contributions_by_date = defaultdict(int)
    contributions_by_repo = defaultdict(list)

    cutoff_date = datetime.now() - timedelta(days=days)

    # Collect all repos
    repos = []

    def update_progress(message: str):
        if progress_callback:
            progress_callback(message)
        logger.info(message)

    # Fetch models
    update_progress(f"Fetching models for {username}...")
    try:
        models = list(api.list_models(author=username))
        for model in models:
            repos.append(("model", model.id))
    except Exception as e:
        logger.warning(f"Error fetching models: {e}")
        models = []

    # Fetch datasets
    update_progress(f"Fetching datasets for {username}...")
    try:
        datasets = list(api.list_datasets(author=username))
        for dataset in datasets:
            repos.append(("dataset", dataset.id))
    except Exception as e:
        logger.warning(f"Error fetching datasets: {e}")
        datasets = []

    # Fetch spaces
    update_progress(f"Fetching spaces for {username}...")
    try:
        spaces = list(api.list_spaces(author=username))
        for space in spaces:
            repos.append(("space", space.id))
    except Exception as e:
        logger.warning(f"Error fetching spaces: {e}")
        spaces = []

    total_repos = len(repos)
    update_progress(f"Found {total_repos} repositories. Fetching commits...")

    # Fetch commits for each repo
    for idx, (repo_type, repo_id) in enumerate(repos):
        update_progress(f"Processing {idx + 1}/{total_repos}: {repo_id}")

        try:
            commits = list(api.list_repo_commits(repo_id, repo_type=repo_type))

            for commit in commits:
                # Handle different date formats
                if hasattr(commit, 'created_at'):
                    commit_date = commit.created_at
                elif hasattr(commit, 'date'):
                    commit_date = commit.date
                else:
                    continue

                # Convert to datetime if string
                if isinstance(commit_date, str):
                    try:
                        commit_date = datetime.fromisoformat(commit_date.replace('Z', '+00:00'))
                    except:
                        continue

                # Skip commits older than cutoff
                if commit_date.replace(tzinfo=None) < cutoff_date:
                    continue

                date_str = commit_date.strftime("%Y-%m-%d")
                contributions_by_date[date_str] += 1

                contributions_by_repo[repo_id].append({
                    "date": date_str,
                    "message": getattr(commit, 'title', getattr(commit, 'message', 'No message')),
                    "repo_type": repo_type
                })

        except Exception as e:
            logger.warning(f"Error fetching commits for {repo_id}: {e}")
            continue

    # Calculate statistics
    total_commits = sum(contributions_by_date.values())
    longest_streak, current_streak = calculate_streaks(contributions_by_date, days)

    most_active_day = None
    most_active_count = 0
    if contributions_by_date:
        most_active_day = max(contributions_by_date, key=contributions_by_date.get)
        most_active_count = contributions_by_date[most_active_day]

    return ContributionStats(
        total_commits=total_commits,
        total_repos=total_repos,
        models_count=len(models),
        datasets_count=len(datasets),
        spaces_count=len(spaces),
        longest_streak=longest_streak,
        current_streak=current_streak,
        most_active_day=most_active_day,
        most_active_count=most_active_count,
        contributions_by_date=dict(contributions_by_date),
        contributions_by_repo=dict(contributions_by_repo)
    )


if __name__ == "__main__":
    # Test with a known active user
    stats = fetch_user_contributions("huggingface")
    print(f"Total commits: {stats.total_commits}")
    print(f"Total repos: {stats.total_repos}")
    print(f"Longest streak: {stats.longest_streak} days")