/**
 * Activity Feed Utilities
 *
 * Combines multiple data sources (check-ins, goals, nutrition) into a unified activity feed
 */

import type { AttendanceStatistics } from "../api/types";
import type { FitnessGoal } from "../services/fitnessGoals";

export enum ActivityType {
  GYM_CHECKIN = "gym_checkin",
  GOAL_COMPLETED = "goal_completed",
  GOAL_CREATED = "goal_created",
  NUTRITION_MILESTONE = "nutrition_milestone",
}

export interface ActivityItem {
  id: string;
  type: ActivityType;
  title: string;
  timestamp: Date;
  duration?: number; // in minutes
  metadata?: Record<string, any>;
}

/**
 * Convert attendance check-ins to activity items
 */
export function checkInsToActivities(
  attendance: AttendanceStatistics,
): ActivityItem[] {
  return attendance.recentCheckIns.map((checkIn) => {
    const checkInDate = new Date(checkIn.checkInTime);

    return {
      id: `checkin-${checkIn.id}`,
      type: ActivityType.GYM_CHECKIN,
      title: "Gym Check-in",
      timestamp: checkInDate,
      duration: checkIn.duration || undefined,
      metadata: {
        checkOutTime: checkIn.checkOutTime,
      },
    };
  });
}

/**
 * Convert completed goals to activity items
 */
export function completedGoalsToActivities(
  goals: FitnessGoal[],
): ActivityItem[] {
  return goals
    .filter((goal) => goal.status === "completed" && goal.completedDate)
    .map((goal) => {
      const completedDate = new Date(goal.completedDate!);

      return {
        id: `goal-completed-${goal.id}`,
        type: ActivityType.GOAL_COMPLETED,
        title: goal.title,
        timestamp: completedDate,
        metadata: {
          goalType: goal.goalType,
          priority: goal.priority,
          targetValue: goal.targetValue,
          unit: goal.unit,
        },
      };
    });
}

/**
 * Convert recently created goals to activity items
 */
export function newGoalsToActivities(
  goals: FitnessGoal[],
  daysBack: number = 7,
): ActivityItem[] {
  const cutoffDate = new Date();
  cutoffDate.setDate(cutoffDate.getDate() - daysBack);

  return goals
    .filter((goal) => {
      const createdDate = new Date(goal.createdAt);
      return goal.status === "active" && createdDate > cutoffDate;
    })
    .map((goal) => {
      const createdDate = new Date(goal.createdAt);

      return {
        id: `goal-created-${goal.id}`,
        type: ActivityType.GOAL_CREATED,
        title: goal.title,
        timestamp: createdDate,
        metadata: {
          goalType: goal.goalType,
          priority: goal.priority,
        },
      };
    });
}

/**
 * Combine and sort all activities by timestamp (most recent first)
 */
export function combineActivities(
  ...activityGroups: ActivityItem[][]
): ActivityItem[] {
  const allActivities = activityGroups.flat();

  return allActivities.sort(
    (a, b) => b.timestamp.getTime() - a.timestamp.getTime(),
  );
}

/**
 * Get recent activities limited to a specific count
 */
export function getRecentActivities(
  activities: ActivityItem[],
  limit: number = 5,
): ActivityItem[] {
  return activities.slice(0, limit);
}

/**
 * Format activity timestamp for display
 */
export function formatActivityTime(timestamp: Date): string {
  const now = new Date();
  const diffMs = now.getTime() - timestamp.getTime();
  const diffMins = Math.floor(diffMs / 60000);
  const diffHours = Math.floor(diffMs / 3600000);
  const diffDays = Math.floor(diffMs / 86400000);

  // Today
  if (diffDays === 0) {
    if (diffMins < 60) {
      return diffMins <= 1 ? "Just now" : `${diffMins}m ago`;
    }
    return `Today, ${timestamp.toLocaleTimeString([], {
      hour: "2-digit",
      minute: "2-digit",
    })}`;
  }

  // Yesterday
  if (diffDays === 1) {
    return `Yesterday, ${timestamp.toLocaleTimeString([], {
      hour: "2-digit",
      minute: "2-digit",
    })}`;
  }

  // This week (within 7 days)
  if (diffDays < 7) {
    return `${diffDays}d ago`;
  }

  // Older
  return timestamp.toLocaleDateString();
}

/**
 * Format duration in minutes to human-readable string
 */
export function formatDuration(minutes?: number): string | undefined {
  if (!minutes) return undefined;

  if (minutes < 60) {
    return `${minutes}m`;
  }

  const hours = Math.floor(minutes / 60);
  const mins = minutes % 60;

  if (mins === 0) {
    return `${hours}h`;
  }

  return `${hours}h ${mins}m`;
}

/**
 * Get icon name for activity type
 */
export function getActivityIcon(type: ActivityType): string {
  switch (type) {
    case ActivityType.GYM_CHECKIN:
      return "barbell";
    case ActivityType.GOAL_COMPLETED:
      return "trophy";
    case ActivityType.GOAL_CREATED:
      return "flag";
    case ActivityType.NUTRITION_MILESTONE:
      return "restaurant";
    default:
      return "checkmark-circle";
  }
}

/**
 * Get activity title prefix/emoji
 */
export function getActivityEmoji(type: ActivityType): string {
  switch (type) {
    case ActivityType.GYM_CHECKIN:
      return "💪";
    case ActivityType.GOAL_COMPLETED:
      return "🏆";
    case ActivityType.GOAL_CREATED:
      return "🎯";
    case ActivityType.NUTRITION_MILESTONE:
      return "🍽️";
    default:
      return "✅";
  }
}