from django.db import models
from tenants.models import Tenant
from users.models import User


class JobCategory(models.Model):
    """
    Job category for organizing job postings.
    """
    name = models.CharField(max_length=100)
    description = models.TextField(blank=True)
    tenant = models.ForeignKey(Tenant, on_delete=models.CASCADE)
    created_at = models.DateTimeField(auto_now_add=True)
    
    def __str__(self):
        return self.name


class Job(models.Model):
    """
    Job posting model for the recruiting platform.
    """
    STATUS_CHOICES = [
        ('draft', 'Draft'),
        ('published', 'Published'),
        ('closed', 'Closed'),
        ('archived', 'Archived'),
    ]
    
    title = models.CharField(max_length=200)
    description = models.TextField()
    requirements = models.TextField()
    responsibilities = models.TextField()
    tenant = models.ForeignKey(Tenant, on_delete=models.CASCADE)
    posted_by = models.ForeignKey(User, on_delete=models.CASCADE, related_name='jobs_posted')
    
    category = models.ForeignKey(JobCategory, on_delete=models.SET_NULL, null=True, blank=True)
    location = models.CharField(max_length=200)
    employment_type = models.CharField(max_length=50, choices=[
        ('full-time', 'Full-time'),
        ('part-time', 'Part-time'),
        ('contract', 'Contract'),
        ('temporary', 'Temporary'),
        ('internship', 'Internship'),
        ('remote', 'Remote'),
    ])
    
    salary_min = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True)
    salary_max = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True)
    
    status = models.CharField(max_length=20, choices=STATUS_CHOICES, default='draft')
    is_remote = models.BooleanField(default=False)
    
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    published_at = models.DateTimeField(null=True, blank=True)
    expires_at = models.DateTimeField(null=True, blank=True)
    
    def __str__(self):
        return f"{self.title} - {self.tenant.name}"
    
    @property
    def is_active(self):
        return self.status == 'published' and self.expires_at and self.expires_at > self.created_at


class Application(models.Model):
    """
    Job application model to track candidate applications.
    """
    STATUS_CHOICES = [
        ('submitted', 'Submitted'),
        ('reviewed', 'Reviewed'),
        ('shortlisted', 'Shortlisted'),
        ('interviewed', 'Interviewed'),
        ('offered', 'Offered'),
        ('rejected', 'Rejected'),
        ('withdrawn', 'Withdrawn'),
    ]
    
    job = models.ForeignKey(Job, on_delete=models.CASCADE, related_name='applications')
    applicant = models.ForeignKey(User, on_delete=models.CASCADE, related_name='applications')
    cover_letter = models.TextField(blank=True)
    status = models.CharField(max_length=20, choices=STATUS_CHOICES, default='submitted')
    
    applied_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)
    
    def __str__(self):
        return f"{self.applicant.username} - {self.job.title}"