from django.db import models
from django_extensions.db.models import TimeStampedModel


class TaskTypeChoices(models.TextChoices):
    CHALLENGE = "challenge", "挑战"
    TUTORIAL = "tutorial", "教程"


class Task(TimeStampedModel):
    display = models.IntegerField(db_index=True, verbose_name="序号")
    title = models.CharField(max_length=100, verbose_name="标题")
    content = models.TextField(verbose_name="内容")
    task_type = models.CharField(
        max_length=20,
        choices=TaskTypeChoices.choices,
        editable=False,
        verbose_name="类型",
    )
    is_public = models.BooleanField(default=False, verbose_name="是否公开")

    class Meta:
        unique_together = ("display", "task_type")

    def save(self, *args, **kwargs):
        if not self.task_type:
            self.task_type = self.__class__.__name__.lower()
        super().save(*args, **kwargs)


class Tutorial(Task):
    def __str__(self):
        return self.title

    class Meta:
        ordering = ("display",)
        verbose_name = "教程"
        verbose_name_plural = verbose_name


class Challenge(Task):
    score = models.IntegerField(default=0)
    pass_score = models.FloatField(null=True, blank=True, verbose_name="通过分数线")

    def __str__(self):
        return self.title

    class Meta:
        ordering = ("display",)
        verbose_name = "挑战"
        verbose_name_plural = verbose_name


def task_asset_upload_to(instance, filename):
    return f"tasks/{instance.task.task_type}/{instance.task.display}/{instance.name}"


class TaskAsset(models.Model):
    task = models.ForeignKey(Task, on_delete=models.CASCADE, related_name="assets")
    name = models.CharField(max_length=100, verbose_name="文件名")
    file = models.FileField(upload_to=task_asset_upload_to, verbose_name="文件")

    class Meta:
        unique_together = ("task", "name")
        verbose_name = "任务素材"
        verbose_name_plural = verbose_name

    def __str__(self):
        return f"{self.task} / {self.name}"