"""
Activity Metrics Data Layer

Provides structured data for training tracking and analysis.

Functions:
    - get_activity_summary_data(): Count, total duration, calories, averages
    - get_activity_detail_data(): Detailed activity log entries
    - get_training_type_distribution_data(): Training category percentages

All functions return structured data (dict) without formatting.
Use placeholder_resolver.py for formatted strings for AI.

Phase 0c: Multi-Layer Architecture
Version: 1.0
"""

from typing import Dict, List, Optional
from datetime import datetime, timedelta, date
from db import get_db, get_cursor, r2d
from data_layer.utils import calculate_confidence, safe_float, safe_int


def get_activity_summary_data(
    profile_id: str,
    days: int = 14
) -> Dict:
    """
    Get activity summary statistics.

    Args:
        profile_id: User profile ID
        days: Analysis window (default 14)

    Returns:
        {
            "activity_count": int,
            "total_duration_min": int,
            "total_kcal": int,
            "avg_duration_min": int,
            "avg_kcal_per_session": int,
            "sessions_per_week": float,
            "confidence": str,
            "days_analyzed": int
        }

    Migration from Phase 0b:
        OLD: get_activity_summary(pid, days) formatted string
        NEW: Structured data with all metrics
    """
    with get_db() as conn:
        cur = get_cursor(conn)
        cutoff = (datetime.now() - timedelta(days=days)).strftime('%Y-%m-%d')

        cur.execute(
            """SELECT
                COUNT(*) as count,
                SUM(duration_min) as total_min,
                SUM(kcal_active) as total_kcal
               FROM activity_log
               WHERE profile_id=%s AND date >= %s""",
            (profile_id, cutoff)
        )
        row = cur.fetchone()

        if not row or row['count'] == 0:
            return {
                "activity_count": 0,
                "total_duration_min": 0,
                "total_kcal": 0,
                "avg_duration_min": 0,
                "avg_kcal_per_session": 0,
                "sessions_per_week": 0.0,
                "confidence": "insufficient",
                "days_analyzed": days
            }

        activity_count = row['count']
        total_min = safe_int(row['total_min'])
        total_kcal = safe_int(row['total_kcal'])

        avg_duration = int(total_min / activity_count) if activity_count > 0 else 0
        avg_kcal = int(total_kcal / activity_count) if activity_count > 0 else 0
        sessions_per_week = (activity_count / days * 7) if days > 0 else 0.0

        confidence = calculate_confidence(activity_count, days, "general")

        return {
            "activity_count": activity_count,
            "total_duration_min": total_min,
            "total_kcal": total_kcal,
            "avg_duration_min": avg_duration,
            "avg_kcal_per_session": avg_kcal,
            "sessions_per_week": round(sessions_per_week, 1),
            "confidence": confidence,
            "days_analyzed": days
        }


def get_activity_detail_data(
    profile_id: str,
    days: int = 14,
    limit: int = 50
) -> Dict:
    """
    Get detailed activity log entries.

    Args:
        profile_id: User profile ID
        days: Analysis window (default 14)
        limit: Maximum entries to return (default 50)

    Returns:
        {
            "activities": [
                {
                    "date": date,
                    "activity_type": str,
                    "duration_min": int,
                    "kcal_active": int,
                    "hr_avg": int | None,
                    "training_category": str | None
                },
                ...
            ],
            "total_count": int,
            "confidence": str,
            "days_analyzed": int
        }

    Migration from Phase 0b:
        OLD: get_activity_detail(pid, days) formatted string list
        NEW: Structured array with all fields
    """
    with get_db() as conn:
        cur = get_cursor(conn)
        cutoff = (datetime.now() - timedelta(days=days)).strftime('%Y-%m-%d')

        cur.execute(
            """SELECT
                date,
                activity_type,
                duration_min,
                kcal_active,
                hr_avg,
                training_category
               FROM activity_log
               WHERE profile_id=%s AND date >= %s
               ORDER BY date DESC
               LIMIT %s""",
            (profile_id, cutoff, limit)
        )
        rows = cur.fetchall()

        if not rows:
            return {
                "activities": [],
                "total_count": 0,
                "confidence": "insufficient",
                "days_analyzed": days
            }

        activities = []
        for row in rows:
            activities.append({
                "date": row['date'],
                "activity_type": row['activity_type'],
                "duration_min": safe_int(row['duration_min']),
                "kcal_active": safe_int(row['kcal_active']),
                "hr_avg": safe_int(row['hr_avg']) if row.get('hr_avg') else None,
                "training_category": row.get('training_category')
            })

        confidence = calculate_confidence(len(activities), days, "general")

        return {
            "activities": activities,
            "total_count": len(activities),
            "confidence": confidence,
            "days_analyzed": days
        }


def get_training_type_distribution_data(
    profile_id: str,
    days: int = 14
) -> Dict:
    """
    Calculate training category distribution.

    Args:
        profile_id: User profile ID
        days: Analysis window (default 14)

    Returns:
        {
            "distribution": [
                {
                    "category": str,
                    "count": int,
                    "percentage": float
                },
                ...
            ],
            "total_sessions": int,
            "categorized_sessions": int,
            "uncategorized_sessions": int,
            "confidence": str,
            "days_analyzed": int
        }

    Migration from Phase 0b:
        OLD: get_trainingstyp_verteilung(pid, days) top 3 formatted
        NEW: Complete distribution with percentages
    """
    with get_db() as conn:
        cur = get_cursor(conn)
        cutoff = (datetime.now() - timedelta(days=days)).strftime('%Y-%m-%d')

        # Get categorized activities
        cur.execute(
            """SELECT
                training_category,
                COUNT(*) as count
               FROM activity_log
               WHERE profile_id=%s
                 AND date >= %s
                 AND training_category IS NOT NULL
               GROUP BY training_category
               ORDER BY count DESC""",
            (profile_id, cutoff)
        )
        rows = cur.fetchall()

        # Get total activity count (including uncategorized)
        cur.execute(
            """SELECT COUNT(*) as total
               FROM activity_log
               WHERE profile_id=%s AND date >= %s""",
            (profile_id, cutoff)
        )
        total_row = cur.fetchone()
        total_sessions = total_row['total'] if total_row else 0

        if not rows or total_sessions == 0:
            return {
                "distribution": [],
                "total_sessions": total_sessions,
                "categorized_sessions": 0,
                "uncategorized_sessions": total_sessions,
                "confidence": "insufficient",
                "days_analyzed": days
            }

        categorized_count = sum(row['count'] for row in rows)
        uncategorized_count = total_sessions - categorized_count

        distribution = []
        for row in rows:
            count = row['count']
            percentage = (count / total_sessions * 100) if total_sessions > 0 else 0
            distribution.append({
                "category": row['training_category'],
                "count": count,
                "percentage": round(percentage, 1)
            })

        confidence = calculate_confidence(categorized_count, days, "general")

        return {
            "distribution": distribution,
            "total_sessions": total_sessions,
            "categorized_sessions": categorized_count,
            "uncategorized_sessions": uncategorized_count,
            "confidence": confidence,
            "days_analyzed": days
        }