from celery import shared_task
import json
import os
import logging
from .models import *
from .serializers import *
from django.core.cache import cache
from django.db import transaction
from superset.models import Superset, SupersetExercise
from exercise.models import Exercise

logger = logging.getLogger(__name__)

@shared_task()
def add_from_files_tasks():
    sample_urls = [{
            "file": os.getcwd() + "/workout/trey_all_workouts.json",
            "user_id": 2
        },{
            "file": os.getcwd() + "/workout/cho_all_workouts.json",
            "user_id": 6
        }]

    for sample_url in sample_urls:
        with open(sample_url["file"]) as user_file:
            file_contents = user_file.read()
            parsed_json = json.loads(file_contents)

            # Fix #7: wrap in try/except so DoesNotExist doesn't crash Celery task
            try:
                registered_user = RegisteredUser.objects.get(pk=sample_url["user_id"])
            except RegisteredUser.DoesNotExist:
                logger.error("RegisteredUser with id=%s does not exist, skipping file %s",
                             sample_url["user_id"], sample_url["file"])
                continue

            for item in parsed_json:
                workout_name = item["name"]
                workout_description = item["description"]
                workout_created = item["created"]

                # Fix #11: wrap bulk operations in transaction.atomic()
                try:
                    with transaction.atomic():
                        workout_obj = Workout.objects.create(
                            registered_user = registered_user,
                            description = workout_description,
                            name = workout_name,
                            created_at = workout_created
                        )

                        # Fix #18: removed first redundant save() after create()
                        # Need the second save to override auto_now_add on created_at
                        workout_obj.created_at = workout_created
                        workout_obj.save(update_fields=['created_at'])
                        workout_total_time = 0

                        supersets = item["supersets"]
                        superset_order = 1
                        for superset in supersets:
                            superset_name = superset["name"]
                            superset_rounds = superset["rounds"]

                            superset_obj = Superset.objects.create(
                                workout=workout_obj,
                                name=superset_name,
                                rounds=superset_rounds,
                                order=superset_order
                            )
                            # Fix #18: removed redundant save() right after create()

                            superset_order += 1

                            exercises = superset["exercises"]
                            exercise_order = 1

                            superset_total_time = 0
                            for exercise in exercises:
                                side = exercise["side"]
                                name = exercise["name"]

                                duration = exercise["duration"]
                                reps = exercise["reps"]
                                side = exercise["side"]

                                # Fix #7: wrap Exercise.objects.get in try/except
                                try:
                                    exercise_obj = None
                                    if len(side) > 0:
                                        exercise_obj = Exercise.objects.get(name=name, side=side)
                                    else:
                                        exercise_obj = Exercise.objects.get(name=name, side="")
                                except Exercise.DoesNotExist:
                                    logger.error("Exercise '%s' (side='%s') does not exist, skipping",
                                                 name, side)
                                    exercise_order += 1
                                    continue

                                supersetExercise = SupersetExercise.objects.create(
                                    superset=superset_obj,
                                    exercise=exercise_obj,
                                    order=exercise_order
                                )

                                if reps != 0:
                                    supersetExercise.reps = reps
                                    # Fix #4: None multiplication risk
                                    superset_total_time += reps * (exercise_obj.estimated_rep_duration or 3.0)
                                if reps == 0 and duration != 0:
                                    supersetExercise.duration = duration
                                    superset_total_time += exercise["duration"]
                                supersetExercise.save()

                                exercise_order += 1

                            superset_obj.estimated_time = superset_total_time
                            superset_obj.save()

                            workout_total_time += (superset_total_time * superset_rounds)

                        workout_obj.estimated_time = workout_total_time
                        workout_obj.save()
                except Exception:
                    logger.exception("Failed to import workout '%s' from %s",
                                     workout_name, sample_url["file"])
                    continue

    # Invalidate per-user cache keys for all imported users
    for sample_url in sample_urls:
        cache.delete('all_workouts_user_' + str(sample_url["user_id"]))