from django.db import models
import secrets


def short_public_id() -> str:
    return "site_" + secrets.token_urlsafe(12)[:16]


class Site(models.Model):
    name = models.CharField(max_length=100)
    site_id = models.CharField(max_length=32, unique=True, default=short_public_id)
    domains = models.JSONField(default=list)          # 域名白名单 ["www.example.com"]
    allow_no_origin = models.BooleanField(default=False)  # 本地/demo 调试用
    is_active = models.BooleanField(default=True)
    timezone = models.CharField(max_length=64, default="Asia/Shanghai")
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "site"


class Visitor(models.Model):
    site = models.ForeignKey(Site, on_delete=models.CASCADE, related_name="visitors")
    visitor_id = models.CharField(max_length=64)
    first_seen_at = models.DateTimeField(auto_now_add=True)
    last_seen_at = models.DateTimeField(auto_now_add=True)
    first_referrer_domain = models.CharField(max_length=200, blank=True, default="")
    first_utm = models.JSONField(default=dict, blank=True)
    first_landing_path = models.CharField(max_length=500, blank=True, default="")
    device_type = models.CharField(max_length=16, blank=True, default="")
    os = models.CharField(max_length=64, blank=True, default="")
    browser = models.CharField(max_length=64, blank=True, default="")
    language = models.CharField(max_length=32, blank=True, default="")
    timezone_name = models.CharField(max_length=64, blank=True, default="")
    screen = models.CharField(max_length=32, blank=True, default="")
    last_ip = models.GenericIPAddressField(null=True, blank=True)
    country = models.CharField(max_length=64, blank=True, default="")
    province = models.CharField(max_length=64, blank=True, default="")
    city = models.CharField(max_length=64, blank=True, default="")
    visit_count = models.PositiveIntegerField(default=0)   # 会话数（服务端按新会话递增）
    active_days = models.PositiveIntegerField(default=0)   # 活跃天数
    last_active_date = models.DateField(null=True, blank=True)
    is_bot = models.BooleanField(default=False)      # UA 爬虫标记，报表默认排除

    class Meta:
        db_table = "visitor"
        constraints = [models.UniqueConstraint(fields=["site", "visitor_id"], name="uq_site_visitor")]
        indexes = [
            models.Index(fields=["site", "-last_seen_at"]),
            models.Index(fields=["site", "country"]),
        ]


class VisitSession(models.Model):
    site = models.ForeignKey(Site, on_delete=models.CASCADE, related_name="sessions")
    visitor = models.ForeignKey(Visitor, on_delete=models.CASCADE, related_name="sessions")
    session_id = models.CharField(max_length=64)
    started_at = models.DateTimeField()
    ended_at = models.DateTimeField()
    referrer_domain = models.CharField(max_length=200, blank=True, default="")
    utm = models.JSONField(default=dict, blank=True)
    landing_path = models.CharField(max_length=500, blank=True, default="")
    event_count = models.PositiveIntegerField(default=0)
    duration_ms = models.PositiveBigIntegerField(default=0)   # 会话内事件时间跨度
    stay_ms = models.PositiveBigIntegerField(default=0)       # 有效停留累计（page_stay active_ms 之和）

    class Meta:
        db_table = "visit_session"
        constraints = [models.UniqueConstraint(fields=["site", "session_id"], name="uq_site_session")]
        indexes = [models.Index(fields=["visitor", "-started_at"])]


class Event(models.Model):
    site = models.ForeignKey(Site, on_delete=models.CASCADE, related_name="events")
    visitor = models.ForeignKey(Visitor, on_delete=models.CASCADE, related_name="events")
    session = models.ForeignKey(VisitSession, on_delete=models.CASCADE, related_name="events", null=True)
    event_id = models.CharField(max_length=64)
    event_name = models.CharField(max_length=50)
    occurred_at = models.DateTimeField()
    received_at = models.DateTimeField(auto_now_add=True)
    path = models.CharField(max_length=500, blank=True, default="")
    title = models.CharField(max_length=200, blank=True, default="")
    properties = models.JSONField(default=dict, blank=True)
    ip = models.GenericIPAddressField(null=True, blank=True)
    country = models.CharField(max_length=64, blank=True, default="")
    province = models.CharField(max_length=64, blank=True, default="")
    city = models.CharField(max_length=64, blank=True, default="")
    late = models.BooleanField(default=False)
    is_bot = models.BooleanField(default=False)

    class Meta:
        db_table = "event"
        constraints = [models.UniqueConstraint(fields=["site", "event_id"], name="uq_site_event")]
        indexes = [
            models.Index(fields=["site", "visitor", "-occurred_at"]),
            models.Index(fields=["session", "occurred_at"]),
            models.Index(fields=["site", "event_name", "-occurred_at"]),
        ]


class DailyStat(models.Model):
    site = models.ForeignKey(Site, on_delete=models.CASCADE, related_name="daily_stats")
    date = models.DateField()
    pv = models.PositiveIntegerField(default=0)
    uv = models.PositiveIntegerField(default=0)
    sessions = models.PositiveIntegerField(default=0)
    new_visitors = models.PositiveIntegerField(default=0)

    class Meta:
        db_table = "daily_stat"
        constraints = [models.UniqueConstraint(fields=["site", "date"], name="uq_site_date")]