from django.db import models
from django.conf import settings

# 7áznamy pro donwloader, co lidé nejvíc stahujou a v jakém formátu
class DownloaderModel(models.Model):
    url = models.URLField()
    download_time = models.DateTimeField(auto_now_add=True)
    status = models.CharField(max_length=50)

    # yt-dlp metadata (flattened for stats)
    requested_format = models.CharField(max_length=100, blank=True, null=True, db_index=True)
    format_id = models.CharField(max_length=50, blank=True, null=True, db_index=True)
    ext = models.CharField(max_length=20, blank=True, null=True, db_index=True)
    vcodec = models.CharField(max_length=50, blank=True, null=True, db_index=True)
    acodec = models.CharField(max_length=50, blank=True, null=True, db_index=True)
    width = models.IntegerField(blank=True, null=True)
    height = models.IntegerField(blank=True, null=True)
    fps = models.FloatField(blank=True, null=True)
    abr = models.FloatField(blank=True, null=True)   # audio bitrate
    vbr = models.FloatField(blank=True, null=True)   # video bitrate
    tbr = models.FloatField(blank=True, null=True)   # total bitrate
    asr = models.IntegerField(blank=True, null=True) # audio sample rate
    filesize = models.BigIntegerField(blank=True, null=True)
    duration = models.FloatField(blank=True, null=True)
    title = models.CharField(max_length=512, blank=True, null=True)
    extractor = models.CharField(max_length=100, blank=True, null=True, db_index=True)
    extractor_key = models.CharField(max_length=100, blank=True, null=True)
    video_id = models.CharField(max_length=128, blank=True, null=True, db_index=True)
    webpage_url = models.URLField(blank=True, null=True)
    is_audio_only = models.BooleanField(default=False, db_index=True)

    # client/context
    user = models.ForeignKey(getattr(settings, "AUTH_USER_MODEL", "auth.User"), on_delete=models.SET_NULL, null=True, blank=True)
    ip_address = models.GenericIPAddressField(blank=True, null=True)
    user_agent = models.TextField(blank=True, null=True)

    # diagnostics
    error_message = models.TextField(blank=True, null=True)

    # full raw yt-dlp info for future analysis
    raw_info = models.JSONField(blank=True, null=True)

    class Meta:
        indexes = [
            models.Index(fields=["download_time"]),
            models.Index(fields=["ext", "is_audio_only"]),
            models.Index(fields=["requested_format"]),
            models.Index(fields=["extractor"]),
        ]

    def __str__(self):
        return f"DownloaderModel {self.id} - {self.status} at {self.download_time.strftime('%d-%m-%Y %H:%M:%S')}"

    @classmethod
    def from_ydl_info(cls, *, info: dict, requested_format: str | None = None, status: str = "success",
                      url: str | None = None, user=None, ip_address: str | None = None,
                      user_agent: str | None = None, error_message: str | None = None):
        # Safe getters
        def g(k, default=None):
            return info.get(k, default)

        instance = cls(
            url=url or g("webpage_url") or g("original_url"),
            status=status,
            requested_format=requested_format,
            format_id=g("format_id"),
            ext=g("ext"),
            vcodec=g("vcodec"),
            acodec=g("acodec"),
            width=g("width") if isinstance(g("width"), int) else None,
            height=g("height") if isinstance(g("height"), int) else None,
            fps=g("fps"),
            abr=g("abr"),
            vbr=g("vbr"),
            tbr=g("tbr"),
            asr=g("asr"),
            filesize=g("filesize") or g("filesize_approx"),
            duration=g("duration"),
            title=g("title"),
            extractor=g("extractor"),
            extractor_key=g("extractor_key"),
            video_id=g("id"),
            webpage_url=g("webpage_url"),
            is_audio_only=(g("vcodec") in (None, "none")),
            user=user if getattr(user, "is_authenticated", False) else None,
            ip_address=ip_address,
            user_agent=user_agent,
            error_message=error_message,
            raw_info=info,
        )
        instance.save()
        return instance