from sqlalchemy import Column, Integer, String, DateTime, Text, JSON, Float, Boolean, ForeignKey
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship
from datetime import datetime

Base = declarative_base()

class PromptTemplate(Base):
    __tablename__ = "prompt_templates"
    id = Column(Integer, primary_key=True)
    template_id = Column(String(64), unique=True, nullable=False)
    name = Column(String(128), nullable=False)
    description = Column(Text, nullable=True)
    template_text = Column(Text, nullable=False)
    variables = Column(JSON, default=[])               # list of variable names
    category = Column(String(64), nullable=True)
    tags = Column(JSON, default=[])                    # list of tags (avoid 'metadata')
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    is_active = Column(Boolean, default=True)
    versions = relationship("PromptVersion", back_populates="template")
    tests = relationship("PromptTest", back_populates="template")

class PromptVersion(Base):
    __tablename__ = "prompt_versions"
    id = Column(Integer, primary_key=True)
    template_id = Column(Integer, ForeignKey("prompt_templates.id"))
    version = Column(Integer, nullable=False)
    template_text = Column(Text, nullable=False)
    variables = Column(JSON, default=[])
    changelog = Column(Text, nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow)
    is_latest = Column(Boolean, default=False)
    template = relationship("PromptTemplate", back_populates="versions")

class PromptTest(Base):
    __tablename__ = "prompt_tests"
    id = Column(Integer, primary_key=True)
    template_id = Column(Integer, ForeignKey("prompt_templates.id"))
    test_id = Column(String(64), unique=True, nullable=False)
    test_input = Column(JSON, default={})              # variable values
    test_output = Column(Text, nullable=True)          # rendered prompt
    passed = Column(Boolean, default=False)
    executed_at = Column(DateTime, default=datetime.utcnow)
    error_message = Column(Text, nullable=True)
    template = relationship("PromptTemplate", back_populates="tests")

class PromptHistory(Base):
    __tablename__ = "prompt_history"
    id = Column(Integer, primary_key=True)
    template_id = Column(Integer, ForeignKey("prompt_templates.id"))
    action = Column(String(32), nullable=False)        # create, update, test, rollback
    details = Column(JSON, default={})
    user_id = Column(String(64), nullable=True)
    created_at = Column(DateTime, default=datetime.utcnow)