from sqlalchemy import text
from sqlalchemy.ext.hybrid import hybrid_property

from .base import db
from .mixins import TrackableMixin
from .queries.template import TemplateQuery, TemplateVersionQuery


class Template(TrackableMixin, db.Model):
    __tablename__ = "template"
    query_class = TemplateQuery

    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(), nullable=False)
    subject = db.Column(db.String(), nullable=False, default="")
    source = db.Column(db.String(), nullable=False)
    context = db.Column(db.String(), nullable=False)
    created_by_id = db.Column(
        db.Integer, db.ForeignKey("dna_account.id"), nullable=True
    )
    updated_by_id = db.Column(
        db.Integer, db.ForeignKey("dna_account.id"), nullable=True
    )
    is_active = db.Column(db.Boolean(), nullable=False, default=False)

    created_by = db.relationship(
        "DNAAccount", backref="created_templates", foreign_keys=[created_by_id]
    )
    updated_by = db.relationship(
        "DNAAccount", backref="updated_templates", foreign_keys=[updated_by_id]
    )

    # Relations
    versions = db.relationship("TemplateVersion", back_populates="template")

    def __repr__(self):
        return f"<Template(id={self.id}, name='{self.name}')>"

    def __str__(self):
        return self.name

    @hybrid_property
    def created_by_name(self):
        return self.created_by.name

    @created_by_name.expression
    def created_by_name(cls):
        return cls.query_class.CREATED_ALIAS.name

    @hybrid_property
    def updated_by_name(self):
        return self.updated_by.name

    @updated_by_name.expression
    def updated_by_name(cls):
        return cls.query_class.UPDATED_ALIAS.name


class TemplateVersion(db.Model):
    __tablename__ = "template_version"
    query_class = TemplateVersionQuery

    id = db.Column(db.Integer, primary_key=True)
    template_id = db.Column(
        db.Integer, db.ForeignKey("template.id"), nullable=False
    )
    name = db.Column(db.String(), nullable=False)
    subject = db.Column(db.String(), nullable=False, default="")
    source = db.Column(db.String(), nullable=False)
    context = db.Column(db.String(), nullable=False)
    created_at = db.Column(
        db.DateTime,
        nullable=False,
        server_default=text("TIMEZONE('utc', CURRENT_TIMESTAMP)"),
    )
    created_by_id = db.Column(
        db.Integer, db.ForeignKey("dna_account.id"), nullable=True
    )

    # Relations
    created_by = db.relationship(
        "DNAAccount",
        backref="created_templates_versions",
        foreign_keys=[created_by_id],
    )
    template = db.relationship("Template", back_populates="versions")

    def __repr__(self):
        return f"<TemplateVersion(id={self.id}, name='{self.name}')>"

    def __str__(self):
        return self.name

    @hybrid_property
    def created_by_name(self):
        return self.created_by.name

    @created_by_name.expression
    def created_by_name(cls):
        return cls.query_class.CREATED_ALIAS.name

    @classmethod
    def from_template(cls, template: Template):
        return cls(
            template_id=template.id,
            name=template.name,
            subject=template.subject,
            source=template.source,
            context=template.context,
            created_by=template.updated_by,
        )