using Microsoft.EntityFrameworkCore;
using TaskTracker.Core.Entities;
using TaskTracker.Core.Enums;
using TaskTracker.Core.Interfaces;
using TaskTracker.Infrastructure.Data;

namespace TaskTracker.Infrastructure.Repositories;

public class TaskRepository(TaskTrackerDbContext db) : ITaskRepository
{
    public async Task<List<WorkTask>> GetAllAsync(WorkTaskStatus? status = null, int? parentId = null, bool includeSubTasks = false)
    {
        var query = db.Tasks.Include(t => t.Notes).Include(t => t.SubTasks).AsQueryable();

        if (status.HasValue)
            query = query.Where(t => t.Status == status.Value);

        if (parentId.HasValue)
            query = query.Where(t => t.ParentTaskId == parentId.Value);
        else if (!includeSubTasks)
            query = query.Where(t => t.ParentTaskId == null);

        return await query.OrderByDescending(t => t.CreatedAt).ToListAsync();
    }

    public async Task<WorkTask?> GetByIdAsync(int id)
    {
        return await db.Tasks
            .Include(t => t.Notes.OrderByDescending(n => n.CreatedAt))
            .Include(t => t.ContextEvents.OrderByDescending(c => c.Timestamp).Take(20))
            .Include(t => t.SubTasks)
            .Include(t => t.ParentTask)
            .FirstOrDefaultAsync(t => t.Id == id);
    }

    public async Task<WorkTask?> GetActiveTaskAsync()
    {
        return await db.Tasks
            .Include(t => t.Notes.OrderByDescending(n => n.CreatedAt))
            .Include(t => t.ContextEvents.OrderByDescending(c => c.Timestamp).Take(20))
            .Include(t => t.SubTasks)
            .Include(t => t.ParentTask)
            .FirstOrDefaultAsync(t => t.Status == WorkTaskStatus.Active);
    }

    public async Task<List<WorkTask>> GetSubTasksAsync(int parentId)
    {
        return await db.Tasks
            .Include(t => t.SubTasks)
            .Where(t => t.ParentTaskId == parentId)
            .OrderByDescending(t => t.CreatedAt)
            .ToListAsync();
    }

    public async Task<WorkTask> CreateAsync(WorkTask task)
    {
        task.CreatedAt = DateTime.UtcNow;
        db.Tasks.Add(task);
        await db.SaveChangesAsync();
        return task;
    }

    public async Task UpdateAsync(WorkTask task)
    {
        db.Tasks.Update(task);
        await db.SaveChangesAsync();
    }

    public async Task DeleteAsync(int id)
    {
        var task = await db.Tasks.Include(t => t.SubTasks).FirstOrDefaultAsync(t => t.Id == id);
        if (task is not null)
        {
            await AbandonDescendantsAsync(task);
            task.Status = WorkTaskStatus.Abandoned;
            await db.SaveChangesAsync();
        }
    }

    private async System.Threading.Tasks.Task AbandonDescendantsAsync(WorkTask task)
    {
        var children = await db.Tasks.Include(t => t.SubTasks).Where(t => t.ParentTaskId == task.Id).ToListAsync();
        foreach (var child in children)
        {
            await AbandonDescendantsAsync(child);
            child.Status = WorkTaskStatus.Abandoned;
        }
    }
}