from uuid import uuid4

from django.db import models
from django.db.models import Count, Q
from tinymce.models import HTMLField

from apps.competition.models import Competition
from apps.core.models import BaseModel
from apps.review.models import ReviewStatusChoices, Review
from apps.user.models import User


class CompetitionTask(BaseModel):
    class CompetitionTaskType(models.TextChoices):
        INPUT = "input", "Ввод правильного ответа"
        CHECKER = "checker", "Ввод кода"
        REVIEW = "review", "Ручная"

    def answer_file_upload_to(instance, filename) -> str:
        return f"/tasks/{instance.id}/answer/{uuid4()}/filename"

    in_competition_position = models.PositiveSmallIntegerField(
        null=True, blank=True
    )
    competition = models.ForeignKey(Competition, on_delete=models.CASCADE)
    title = models.CharField(verbose_name="заголовок", max_length=50)
    description = HTMLField(verbose_name="описание", max_length=300)
    max_attempts = models.PositiveSmallIntegerField(null=True, blank=True)
    type = models.CharField(
        choices=CompetitionTaskType, max_length=8, verbose_name="тип проверки"
    )

    # only when "input" or "checker" type
    correct_answer_file = models.FileField(
        upload_to=answer_file_upload_to,
        null=True,
        blank=True,
        verbose_name="файл с правильным ответом",
    )
    points = models.IntegerField(
        null=True, blank=True, verbose_name="баллы за задание"
    )

    # only when "checker" type
    answer_file_path = models.TextField(
        null=True,
        blank=True,
        verbose_name="куда сделать вывод программы участнику",
        help_text="Путь до файла в котором ожидается результат. Пример: stdout или ./output.txt",
        default="stdout",
    )

    def __str__(self):
        return self.title

    class Meta:
        verbose_name = "задание"
        verbose_name_plural = "задания"


class CompetitionTaskCriteria(BaseModel):
    task = models.ForeignKey(
        CompetitionTask, on_delete=models.CASCADE, related_name="criteries"
    )

    name = models.TextField()
    slug = models.SlugField()
    description = models.TextField()
    max_value = models.PositiveSmallIntegerField()


class CompetitionTaskAttachment(BaseModel):
    def file_upload_at(instance, filename):
        return f"/attachment/{instance.id}/file"

    task = models.ForeignKey(CompetitionTask, on_delete=models.CASCADE,
                             verbose_name="задание")
    file = models.FileField(upload_to=file_upload_at,
                            verbose_name="файл")
    bind_at = models.FilePathField(verbose_name="путь сохранения")
    public = models.BooleanField(default=False, verbose_name="публичный")


class CompetitionTaskSubmission(BaseModel):
    class StatusChoices(models.TextChoices):
        SENT = "sent"
        CHECKING = "checking"
        CHECKED = "checked"

    def submission_content_upload_to(instance, filename) -> str:
        return f"submissions/{instance.id}/content"

    def submission_stdout_upload_to(instance, filename) -> str:
        return f"/submissions/{instance.id}/stdout"

    user = models.ForeignKey(User, on_delete=models.CASCADE,
                             verbose_name="пользователь")
    task = models.ForeignKey(CompetitionTask, on_delete=models.CASCADE,
                             verbose_name="задание")

    status = models.CharField(
        choices=StatusChoices.choices,
        default=StatusChoices.SENT,
        max_length=8,
        verbose_name="статус"
    )

    # code or text or file
    content = models.FileField(upload_to=submission_content_upload_to,
                               verbose_name="код/файл посылки")

    # only if task type is checker
    stdout = models.FileField(
        upload_to=submission_stdout_upload_to, null=True, blank=True,
        verbose_name="вывод чекера"
    )

    # depends on task type:
    # - input: {"correct": boolean}
    # - file: {"total_points": integer, "by_criteria": ["criteria_name": integer]}
    # - code: {"correct": boolean}
    result = models.JSONField(default=None, null=True, blank=True,
                              verbose_name="результат проверки")
    # just more readable result representation, maybe will be calcuated somehow more complex depends on criteria
    earned_points = models.IntegerField(null=True, blank=True,
                                        verbose_name="получено баллов")

    checked_at = models.DateTimeField(null=True, blank=True,
                                      verbose_name="дата и время проверки")
    plagiarism_checked = models.BooleanField(default=False,
                                             verbose_name="проверено на плагиат")
    timestamp = models.DateTimeField(auto_now_add=True,
                                     verbose_name="дата отправки")

    def __str__(self):
        return str(self.id)

    class Meta:
        verbose_name = "посылка"
        verbose_name_plural = "посылки"

    def send_on_review(self):
        if not self.task.reviewers.exists():
            return

        reviewer = (
            self.task.reviewers.annotate(
                pending_count=Count(
                    "review",
                    filter=Q(
                        review__state__in=[
                            ReviewStatusChoices.NOT_CHECKED,
                            ReviewStatusChoices.CHECKING,
                        ]
                    ),
                )
            )
            .order_by("pending_count")
            .first()
        )
        Review.objects.create(
            reviewer=reviewer,
            submission=self,
        )