import os
from datetime import date
from django.db import models
from django.utils.translation import gettext_lazy as _
from PIL import Image
from io import BytesIO
from django.core.files.base import ContentFile
from loguru import logger


class DeviceStatus(models.TextChoices):
    NORMAL = 'normal', _('正常')
    WARNING = 'warning', _('告警')
    OFFLINE = 'offline', _('离线')
    REPAIR = 'repair', _('维修中')
    SCRAP = 'scrap', _('已报废')


def device_attachment_path(instance, filename):
    return f'devices/{instance.id}/attachments/{filename}'


def device_thumbnail_path(instance, filename):
    return f'devices/{instance.id}/thumbnails/{filename}'


class Device(models.Model):
    location = models.CharField(max_length=100, verbose_name='地点')
    building = models.CharField(max_length=50, blank=True, null=True, verbose_name='楼栋')
    floor = models.CharField(max_length=20, blank=True, null=True, verbose_name='楼层')
    cabinet = models.CharField(max_length=50, blank=True, null=True, verbose_name='机柜')
    device_name = models.CharField(max_length=100, verbose_name='设备名称')
    model = models.CharField(max_length=100, blank=True, null=True, verbose_name='型号')
    brand = models.CharField(max_length=100, blank=True, null=True, verbose_name='品牌')
    mac_address = models.CharField(max_length=17, blank=True, null=True, verbose_name='MAC地址')
    enable_date = models.DateField(blank=True, null=True, verbose_name='启用日期')
    last_inspection_date = models.DateField(blank=True, null=True, verbose_name='最后巡检日期')
    thumbnail = models.ImageField(upload_to=device_thumbnail_path, blank=True, null=True, verbose_name='缩略图')
    status = models.CharField(
        max_length=20,
        choices=DeviceStatus.choices,
        default=DeviceStatus.NORMAL,
        verbose_name='状态'
    )
    responsible_person = models.CharField(max_length=50, blank=True, null=True, verbose_name='运维人员')
    warranty_expire = models.DateField(blank=True, null=True, verbose_name='保修到期日期')
    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
    updated_at = models.DateTimeField(auto_now=True, verbose_name='更新时间')

    class Meta:
        db_table = 'device'
        verbose_name = '设备'
        verbose_name_plural = '设备'
        indexes = [
            models.Index(fields=['location', 'building']),
            models.Index(fields=['status']),
        ]

    def __str__(self):
        return f'{self.device_name} - {self.location}'

    @property
    def service_duration_days(self):
        if self.enable_date:
            return (date.today() - self.enable_date).days
        return 0

    @property
    def is_warranty_expired(self):
        if self.warranty_expire:
            return date.today() > self.warranty_expire
        return False

    def generate_thumbnail(self, image_field, size=(200, 200)):
        if not image_field:
            return
        
        try:
            img = Image.open(image_field)
            if img.mode in ('RGBA', 'P'):
                img = img.convert('RGB')
            
            img.thumbnail(size)
            thumb_io = BytesIO()
            img.save(thumb_io, format='JPEG', quality=85)
            
            thumb_name = f'thumb_{os.path.basename(image_field.name)}'
            self.thumbnail.save(thumb_name, ContentFile(thumb_io.getvalue()), save=False)
            logger.info(f'Generated thumbnail for device {self.id}')
        except Exception as e:
            logger.error(f'Failed to generate thumbnail: {e}')

    def save(self, *args, **kwargs):
        super().save(*args, **kwargs)


class DeviceSerial(models.Model):
    device = models.ForeignKey(Device, on_delete=models.CASCADE, related_name='serials', verbose_name='设备')
    serial_number = models.CharField(max_length=100, unique=True, verbose_name='序列号')
    serial_type = models.CharField(max_length=50, default='main', verbose_name='序列号类型')
    is_primary = models.BooleanField(default=False, verbose_name='是否主序列号')
    remark = models.CharField(max_length=255, blank=True, null=True, verbose_name='备注')
    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
    updated_at = models.DateTimeField(auto_now=True, verbose_name='更新时间')

    class Meta:
        db_table = 'device_serial'
        verbose_name = '设备序列号'
        verbose_name_plural = '设备序列号'

    def __str__(self):
        return f'{self.serial_number} ({self.serial_type})'


class DeviceIP(models.Model):
    device = models.ForeignKey(Device, on_delete=models.CASCADE, related_name='ips', verbose_name='设备')
    ip_address = models.CharField(max_length=45, unique=True, verbose_name='IP地址')
    ip_type = models.CharField(max_length=20, default='management', verbose_name='IP类型')
    is_primary = models.BooleanField(default=False, verbose_name='是否主IP')
    subnet_mask = models.CharField(max_length=15, blank=True, null=True, verbose_name='子网掩码')
    gateway = models.CharField(max_length=45, blank=True, null=True, verbose_name='网关')
    vlan_id = models.CharField(max_length=10, blank=True, null=True, verbose_name='VLAN ID')
    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
    updated_at = models.DateTimeField(auto_now=True, verbose_name='更新时间')

    class Meta:
        db_table = 'device_ip'
        verbose_name = '设备IP地址'
        verbose_name_plural = '设备IP地址'

    def __str__(self):
        return f'{self.ip_address} ({self.ip_type})'


class MaintenanceRecord(models.Model):
    device = models.ForeignKey(Device, on_delete=models.CASCADE, related_name='maintenance_records', verbose_name='设备')
    maintenance_date = models.DateField(verbose_name='维修日期')
    fault_description = models.TextField(blank=True, null=True, verbose_name='故障描述')
    repair_content = models.TextField(blank=True, null=True, verbose_name='维修内容')
    replaced_parts = models.CharField(max_length=255, blank=True, null=True, verbose_name='更换配件')
    maintenance_by = models.CharField(max_length=50, blank=True, null=True, verbose_name='维修人')
    cost = models.DecimalField(max_digits=10, decimal_places=2, blank=True, null=True, verbose_name='费用')
    remark = models.TextField(blank=True, null=True, verbose_name='备注')
    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
    updated_at = models.DateTimeField(auto_now=True, verbose_name='更新时间')

    class Meta:
        db_table = 'maintenance_record'
        verbose_name = '维修记录'
        verbose_name_plural = '维修记录'
        ordering = ['-maintenance_date']

    def __str__(self):
        return f'{self.device.device_name} - {self.maintenance_date}'


class DeviceAttachment(models.Model):
    device = models.ForeignKey(Device, on_delete=models.CASCADE, related_name='attachments', verbose_name='设备')
    file = models.FileField(upload_to=device_attachment_path, verbose_name='文件')
    file_name = models.CharField(max_length=255, verbose_name='文件名')
    file_type = models.CharField(max_length=50, blank=True, null=True, verbose_name='文件类型')
    uploaded_at = models.DateTimeField(auto_now_add=True, verbose_name='上传时间')

    class Meta:
        db_table = 'device_attachment'
        verbose_name = '设备附件'
        verbose_name_plural = '设备附件'

    def __str__(self):
        return self.file_name