import uuid
from django.db import models

class TaskStatus(models.TextChoices):
    DRAFT = 'DRAFT', '草稿'
    OPEN = 'OPEN', '已发布'
    IN_PROGRESS = 'IN_PROGRESS', '进行中'
    IN_REVIEW = 'IN_REVIEW', '待验收'
    COMPLETED = 'COMPLETED', '已完成'
    CANCELLED = 'CANCELLED', '已取消'

class ApplyStatus(models.TextChoices):
    PENDING = 'PENDING', '待审核'
    APPROVED = 'APPROVED', '已录用'
    REJECTED = 'REJECTED', '已拒绝'
    WITHDRAWN = 'WITHDRAWN', '已撤回'
    DELIVERED = 'DELIVERED', '交付待验收'
    COMPLETED = 'COMPLETED', '已完成'

class Task(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    publisher = models.ForeignKey('users.User', on_delete=models.CASCADE, related_name='published_tasks')
    enterprise = models.ForeignKey('users.Enterprise', on_delete=models.SET_NULL, null=True, blank=True, related_name='tasks')
    title = models.CharField(max_length=256)
    description = models.TextField()
    skill_tags = models.JSONField(default=list)
    budget_min = models.DecimalField(max_digits=12, decimal_places=2, null=True, blank=True)
    budget_max = models.DecimalField(max_digits=12, decimal_places=2, null=True, blank=True)
    currency = models.CharField(max_length=8, default='CNY')
    deadline = models.DateField(null=True, blank=True)
    task_type = models.CharField(max_length=64, null=True, blank=True)
    attachments = models.JSONField(default=list)
    contact_user = models.ForeignKey('users.User', on_delete=models.SET_NULL, null=True, blank=True, related_name='+')
    contact_name = models.CharField(max_length=64, null=True, blank=True)
    contact_phone = models.CharField(max_length=32, null=True, blank=True)
    contact_email = models.EmailField(null=True, blank=True)
    contact_wechat = models.CharField(max_length=64, null=True, blank=True)
    status = models.CharField(max_length=16, choices=TaskStatus.choices, default=TaskStatus.DRAFT)
    assignee = models.ForeignKey('users.User', on_delete=models.SET_NULL, null=True, blank=True, related_name='assigned_tasks')
    assigned_at = models.DateTimeField(null=True, blank=True)
    completed_at = models.DateTimeField(null=True, blank=True)
    completion_note = models.TextField(null=True, blank=True)
    deliverables = models.JSONField(default=list)
    cancelled_at = models.DateTimeField(null=True, blank=True)
    cancel_reason = models.TextField(null=True, blank=True)
    is_deleted = models.BooleanField(default=False)
    is_recommended = models.BooleanField(default=False, help_text='管理员推荐')
    recommend_priority = models.IntegerField(default=0, help_text='推荐优先级, 越大越靠前')
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = 'tasks'
        ordering = ['-is_recommended', '-recommend_priority', '-created_at']

class TaskApplication(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    task = models.ForeignKey(Task, on_delete=models.CASCADE, related_name='applications')
    applicant = models.ForeignKey('users.User', on_delete=models.CASCADE, related_name='task_applications')
    cover_letter = models.TextField(null=True, blank=True)
    expected_days = models.IntegerField(null=True, blank=True)
    expected_price = models.DecimalField(max_digits=12, decimal_places=2, null=True, blank=True)
    attachments = models.JSONField(default=list)
    negotiation_history = models.JSONField(default=list)
    status = models.CharField(max_length=16, choices=ApplyStatus.choices, default=ApplyStatus.PENDING)
    reject_reason = models.TextField(null=True, blank=True)
    reviewed_by = models.ForeignKey('users.User', on_delete=models.SET_NULL, null=True, blank=True, related_name='reviewed_applications')
    reviewed_at = models.DateTimeField(null=True, blank=True)
    deliverables = models.JSONField(default=list)
    completion_note = models.TextField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = 'task_applications'
        unique_together = ('task', 'applicant')
        ordering = ['-created_at']

class InvitationStatus(models.TextChoices):
    PENDING = 'PENDING', '待处理'
    ACCEPTED = 'ACCEPTED', '已接受'
    REJECTED = 'REJECTED', '已拒绝'
    DISCUSSING = 'DISCUSSING', '洽谈中'

class TaskInvitation(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    task = models.ForeignKey(Task, on_delete=models.CASCADE, related_name='invitations')
    expert = models.ForeignKey('users.User', on_delete=models.CASCADE, related_name='task_invitations')
    message = models.TextField(null=True, blank=True)
    messages = models.JSONField(default=list)
    status = models.CharField(max_length=16, choices=InvitationStatus.choices, default=InvitationStatus.PENDING)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = 'task_invitations'
        unique_together = ('task', 'expert')
        ordering = ['-created_at']

class DeliveryStatus(models.TextChoices):
    PENDING = 'PENDING', '待验收'
    APPROVED = 'APPROVED', '已验收'
    REJECTED = 'REJECTED', '已驳回'

class DeliveryRecord(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    application = models.ForeignKey(TaskApplication, on_delete=models.CASCADE, related_name='delivery_records')
    note = models.TextField()
    files = models.JSONField(default=list)
    status = models.CharField(max_length=16, choices=DeliveryStatus.choices, default=DeliveryStatus.PENDING)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = 'delivery_records'
        ordering = ['-created_at']

class TaskReview(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    task = models.OneToOneField(Task, on_delete=models.CASCADE, related_name='review')
    reviewer = models.ForeignKey('users.User', on_delete=models.CASCADE, related_name='given_reviews')
    reviewee = models.ForeignKey('users.User', on_delete=models.CASCADE, related_name='received_reviews')
    score = models.IntegerField(default=5) # 1 to 5
    comment = models.TextField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)
    
    class Meta:
        db_table = 'task_reviews'
        ordering = ['-created_at']