# models/database/media.py
"""
Media file models for vendor media library.

This module provides:
- MediaFile: Vendor-uploaded media files (images, documents, videos)
- ProductMedia: Many-to-many relationship between products and media

Files are stored in vendor-specific directories:
  uploads/vendors/{vendor_id}/{folder}/{filename}
"""

from datetime import datetime

from sqlalchemy import (
    Boolean,
    Column,
    DateTime,
    ForeignKey,
    Index,
    Integer,
    String,
    Text,
    UniqueConstraint,
)
from sqlalchemy.dialects.sqlite import JSON
from sqlalchemy.orm import relationship

from app.core.database import Base
from models.database.base import TimestampMixin


class MediaFile(Base, TimestampMixin):
    """Vendor media file record.

    Stores metadata about uploaded files. Actual files are stored
    in the filesystem at uploads/vendors/{vendor_id}/{folder}/
    """

    __tablename__ = "media_files"

    id = Column(Integer, primary_key=True, index=True)
    vendor_id = Column(Integer, ForeignKey("vendors.id"), nullable=False)

    # File identification
    filename = Column(String(255), nullable=False)  # Stored filename (UUID-based)
    original_filename = Column(String(255))  # Original uploaded filename
    file_path = Column(String(500), nullable=False)  # Relative path from uploads/

    # File properties
    media_type = Column(String(20), nullable=False)  # image, video, document
    mime_type = Column(String(100))
    file_size = Column(Integer)  # bytes

    # Image/video dimensions
    width = Column(Integer)
    height = Column(Integer)

    # Thumbnail (for images/videos)
    thumbnail_path = Column(String(500))

    # Metadata
    alt_text = Column(String(500))
    description = Column(Text)
    folder = Column(String(100), default="general")  # products, general, etc.
    tags = Column(JSON)  # List of tags for categorization
    extra_metadata = Column(JSON)  # Additional metadata (EXIF, etc.)

    # Status
    is_optimized = Column(Boolean, default=False)
    optimized_size = Column(Integer)  # Size after optimization

    # Usage tracking
    usage_count = Column(Integer, default=0)  # How many times used

    # Relationships
    vendor = relationship("Vendor", back_populates="media_files")
    product_associations = relationship(
        "ProductMedia",
        back_populates="media",
        cascade="all, delete-orphan",
    )

    __table_args__ = (
        Index("idx_media_vendor_id", "vendor_id"),
        Index("idx_media_vendor_folder", "vendor_id", "folder"),
        Index("idx_media_vendor_type", "vendor_id", "media_type"),
        Index("idx_media_filename", "filename"),
    )

    def __repr__(self):
        return (
            f"<MediaFile(id={self.id}, vendor_id={self.vendor_id}, "
            f"filename='{self.filename}', type='{self.media_type}')>"
        )

    @property
    def file_url(self) -> str:
        """Get the public URL for this file."""
        return f"/uploads/{self.file_path}"

    @property
    def thumbnail_url(self) -> str | None:
        """Get the thumbnail URL if available."""
        if self.thumbnail_path:
            return f"/uploads/{self.thumbnail_path}"
        return None

    @property
    def is_image(self) -> bool:
        """Check if this is an image file."""
        return self.media_type == "image"

    @property
    def is_video(self) -> bool:
        """Check if this is a video file."""
        return self.media_type == "video"

    @property
    def is_document(self) -> bool:
        """Check if this is a document file."""
        return self.media_type == "document"


class ProductMedia(Base, TimestampMixin):
    """Association between products and media files.

    Tracks which media files are used by which products,
    including the usage type (main image, gallery, variant, etc.)
    """

    __tablename__ = "product_media"

    id = Column(Integer, primary_key=True, index=True)
    product_id = Column(
        Integer,
        ForeignKey("products.id", ondelete="CASCADE"),
        nullable=False,
    )
    media_id = Column(
        Integer,
        ForeignKey("media_files.id", ondelete="CASCADE"),
        nullable=False,
    )

    # Usage type
    usage_type = Column(String(50), nullable=False, default="gallery")
    # Types: main_image, gallery, variant, thumbnail, swatch

    # Display order for galleries
    display_order = Column(Integer, default=0)

    # Variant-specific (if usage_type is variant)
    variant_id = Column(Integer)  # Reference to variant if applicable

    # Relationships
    product = relationship("Product")
    media = relationship("MediaFile", back_populates="product_associations")

    __table_args__ = (
        UniqueConstraint(
            "product_id", "media_id", "usage_type",
            name="uq_product_media_usage"
        ),
        Index("idx_product_media_product", "product_id"),
        Index("idx_product_media_media", "media_id"),
    )

    def __repr__(self):
        return (
            f"<ProductMedia(product_id={self.product_id}, "
            f"media_id={self.media_id}, usage='{self.usage_type}')>"
        )