from django.db import models
from core.models.profile import TeamProfile
from core.models.account import Account, AccountAddress
from core.models.project import Project
from core.models.base import BaseModel


class ProjectScope(BaseModel):
    """Scope of work definition for a project"""
    name = models.CharField(max_length=255)
    account = models.ForeignKey(
        Account,
        on_delete=models.PROTECT,
        related_name='project_scopes',
        blank=True,
        null=True,
    )
    project = models.ForeignKey(Project, on_delete=models.PROTECT, related_name='project_scopes')
    account_address = models.ForeignKey(
        AccountAddress,
        on_delete=models.PROTECT,
        related_name='project_scopes',
        null=True,
        blank=True,
    )
    description = models.TextField(blank=True)
    is_active = models.BooleanField(default=True)

    class Meta:
        ordering = ['name']
        verbose_name = "Project Scope"
        verbose_name_plural = "Project Scopes"
        indexes = [
            models.Index(fields=['project', 'is_active']),
            models.Index(fields=['account_address', 'is_active']),
        ]
        constraints = [
            # Ensure only one active scope per project/address combination (when address present)
            models.UniqueConstraint(
                fields=['project', 'account_address'],
                condition=models.Q(is_active=True, account_address__isnull=False),
                name='unique_active_project_scope_per_address',
            ),
        ]

    def __str__(self):
        project_label = str(self.project_id) if self.project_id else "Unassigned Project"
        return f"{self.name} - {project_label}"


class ProjectScopeCategory(BaseModel):
    """Category of work definition for a project"""
    name = models.CharField(max_length=255)
    scope = models.ForeignKey(ProjectScope, on_delete=models.CASCADE, related_name='project_areas')
    order = models.PositiveIntegerField(default=0)

    class Meta:
        ordering = ['scope', 'order', 'name']
        verbose_name = "Project Scope Category"
        verbose_name_plural = "Project Scope Categories"
        indexes = [
            models.Index(fields=['scope', 'order']),
        ]

    def __str__(self):
        return f"{self.scope.name} - {self.name}"


class ProjectScopeTask(BaseModel):
    """Specific task definition for a project"""
    category = models.ForeignKey(ProjectScopeCategory, on_delete=models.CASCADE, related_name='project_tasks')
    description = models.TextField()
    checklist_description = models.TextField()
    order = models.PositiveIntegerField(default=0)
    estimated_minutes = models.PositiveIntegerField(null=True, blank=True)

    class Meta:
        ordering = ['category', 'order']
        verbose_name = "Project Scope Task"
        verbose_name_plural = "Project Scope Tasks"
        indexes = [
            models.Index(fields=['category', 'order']),
        ]

    def __str__(self):
        return f"{self.category.name}: {self.description[:50]}..."


class ProjectScopeTaskCompletion(BaseModel):
    """Record of a task template being completed during a project"""
    task = models.ForeignKey(ProjectScopeTask, on_delete=models.PROTECT, related_name='completions')
    project = models.ForeignKey(Project, on_delete=models.PROTECT, related_name='task_completions')
    account = models.ForeignKey(Account, on_delete=models.PROTECT, related_name='task_completions', null=True, blank=True)
    account_address = models.ForeignKey(AccountAddress, on_delete=models.PROTECT, null=True, blank=True, related_name='project_task_completions')
    completed_by = models.ForeignKey(TeamProfile, on_delete=models.PROTECT)
    completed_at = models.DateTimeField()
    notes = models.TextField(blank=True)