from django.db import models

from netscan.fields import EncryptedCharField


class NginxSettings(models.Model):
    """
    Singleton (pk=1) — the one-off cluster connection config.
    Use NginxSettings.get() everywhere instead of pk lookups.
    """
    namespace = models.CharField(max_length=200, default='ingress-nginx')
    pod_label = models.CharField(
        max_length=200,
        default='app.kubernetes.io/name=ingress-nginx',
        help_text='kubectl -l selector for the ingress-nginx pods',
    )
    container = models.CharField(max_length=100, default='controller')
    fetch_interval_seconds = models.IntegerField(
        default=30,
        help_text='How often to pull new logs (seconds)',
    )
    # Local dev / testing: read from a file instead of kubectl
    log_file_path = models.CharField(
        max_length=500,
        blank=True,
        help_text=(
            'Absolute path to a local nginx log file for testing. '
            'Leave empty to use kubectl in production.'
        ),
    )
    enabled = models.BooleanField(default=True)
    last_fetch_at = models.DateTimeField(null=True, blank=True)

    class Meta:
        verbose_name = 'Nginx Settings'
        verbose_name_plural = 'Nginx Settings'

    def __str__(self):
        return f'Nginx Settings ({self.namespace})'

    @classmethod
    def get(cls):
        obj, _ = cls.objects.get_or_create(pk=1)
        return obj

    @property
    def source_display(self):
        if self.log_file_path:
            return f'File: {self.log_file_path}'
        return f'kubectl -n {self.namespace} -l {self.pod_label}'


class NginxAlertProfile(models.Model):
    """
    One or more alert profiles — each with its own thresholds and Telegram config.
    """
    name = models.CharField(max_length=200)
    alert_window_seconds = models.IntegerField(
        default=60,
        help_text='Rolling window in seconds for rate analysis',
    )
    alert_max_requests = models.IntegerField(
        default=200,
        help_text='Max requests per IP per window before triggering a rate alert',
    )
    alert_max_error_rate = models.FloatField(
        default=0.6,
        help_text='Error rate threshold (0–1) to flag an IP',
    )
    alert_min_requests = models.IntegerField(
        default=15,
        help_text='Minimum requests before running error-rate check',
    )
    telegram_bot_token = EncryptedCharField(blank=True)
    telegram_chat_id = EncryptedCharField(blank=True)
    enabled = models.BooleanField(default=True)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return self.name


class NginxAccessLog(models.Model):
    """Stores parsed nginx access log entries (cluster-global, no profile FK)."""
    timestamp = models.DateTimeField(db_index=True)
    remote_addr = models.GenericIPAddressField(db_index=True)
    method = models.CharField(max_length=20)
    request_uri = models.TextField()
    protocol = models.CharField(max_length=20)
    status = models.IntegerField(db_index=True)
    body_bytes_sent = models.IntegerField()
    http_referer = models.TextField(blank=True)
    http_user_agent = models.TextField(blank=True)
    request_length = models.IntegerField(default=0)
    request_time = models.FloatField()
    service = models.CharField(max_length=200, blank=True, db_index=True)
    upstream_addr = models.CharField(max_length=200, blank=True)
    upstream_response_time = models.FloatField(null=True, blank=True)
    upstream_status = models.IntegerField(null=True, blank=True)
    request_id = models.CharField(max_length=100, blank=True, db_index=True)
    # Geo (populated after insert)
    country = models.CharField(max_length=100, blank=True)
    country_code = models.CharField(max_length=10, blank=True)
    region = models.CharField(max_length=100, blank=True)
    city = models.CharField(max_length=100, blank=True)

    class Meta:
        ordering = ['-timestamp']
        indexes = [
            models.Index(fields=['remote_addr', 'timestamp']),
            models.Index(fields=['timestamp', 'status']),  # covers chart aggregation queries
        ]

    @property
    def geo_display(self):
        parts = [p for p in [self.city, self.country] if p]
        return ', '.join(parts) if parts else '—'


class IPGeoCache(models.Model):
    ip = models.GenericIPAddressField(unique=True, db_index=True)
    country = models.CharField(max_length=100, blank=True)
    country_code = models.CharField(max_length=10, blank=True)
    region = models.CharField(max_length=100, blank=True)
    city = models.CharField(max_length=100, blank=True)
    lat = models.FloatField(null=True, blank=True)
    lon = models.FloatField(null=True, blank=True)
    isp = models.CharField(max_length=300, blank=True)
    is_private = models.BooleanField(default=False)
    fetched_at = models.DateTimeField(auto_now=True)

    def __str__(self):
        if self.is_private:
            return f'{self.ip} (private)'
        parts = [p for p in [self.city, self.country] if p]
        return f'{self.ip} — {", ".join(parts)}'


class ThreatAlert(models.Model):
    ALERT_TYPES = [
        ('rate_limit', 'High Request Rate'),
        ('error_rate', 'High Error Rate'),
    ]

    profile = models.ForeignKey(
        NginxAlertProfile, on_delete=models.CASCADE, related_name='alerts'
    )
    alert_type = models.CharField(max_length=50, choices=ALERT_TYPES)
    remote_addr = models.GenericIPAddressField(db_index=True)
    detected_at = models.DateTimeField(auto_now_add=True)
    window_start = models.DateTimeField()
    window_end = models.DateTimeField()
    request_count = models.IntegerField()
    error_count = models.IntegerField(default=0)
    detail = models.TextField()
    notified = models.BooleanField(default=False)
    dismissed = models.BooleanField(default=False)
    country = models.CharField(max_length=100, blank=True)
    city = models.CharField(max_length=100, blank=True)

    class Meta:
        ordering = ['-detected_at']

    def __str__(self):
        return f'[{self.get_alert_type_display()}] {self.remote_addr} @ {self.detected_at:%Y-%m-%d %H:%M}'

    @property
    def error_rate(self):
        return self.error_count / self.request_count if self.request_count else 0