"""initial schema: documents, chunks (pgvector), query_log

Revision ID: 0001
Revises:
Create Date: 2026-08-21

"""
from __future__ import annotations

import sqlalchemy as sa
from pgvector.sqlalchemy import Vector
from sqlalchemy.dialects import postgresql

from alembic import op

EMBEDDING_DIM = 768  # keep in sync with app/models.py (PLAN anchor A6)

revision = "0001"
down_revision = None
branch_labels = None
depends_on = None


def upgrade() -> None:
    op.execute("CREATE EXTENSION IF NOT EXISTS vector")

    op.create_table(
        "documents",
        sa.Column("id", postgresql.UUID(as_uuid=True), primary_key=True),
        sa.Column("source", sa.String(120), nullable=False),
        sa.Column("path", sa.String(1000), nullable=False),
        sa.Column("full_path", sa.String(2000), nullable=False),
        sa.Column("title", sa.String(500), nullable=False),
        sa.Column("content", sa.Text(), nullable=False),
        sa.Column("content_hash", sa.String(64), nullable=False),
        sa.Column(
            "indexed_at",
            sa.DateTime(timezone=True),
            server_default=sa.func.now(),
            nullable=False,
        ),
        sa.UniqueConstraint("source", "path", name="uq_documents_source_path"),
    )
    op.create_index("ix_documents_source", "documents", ["source"])
    op.create_index("ix_documents_path", "documents", ["path"])
    op.create_index("ix_documents_content_hash", "documents", ["content_hash"])

    op.create_table(
        "chunks",
        sa.Column("id", postgresql.UUID(as_uuid=True), primary_key=True),
        sa.Column(
            "document_id",
            postgresql.UUID(as_uuid=True),
            sa.ForeignKey("documents.id", ondelete="CASCADE"),
            nullable=False,
        ),
        sa.Column("position", sa.Integer(), nullable=False),
        sa.Column("content", sa.Text(), nullable=False),
        sa.Column("embedding", Vector(EMBEDDING_DIM), nullable=True),
    )
    op.create_index("ix_chunks_document_id", "chunks", ["document_id"])

    op.create_table(
        "query_log",
        sa.Column("id", postgresql.UUID(as_uuid=True), primary_key=True),
        sa.Column("question", sa.Text(), nullable=False),
        sa.Column("top_score", sa.Float(), nullable=False, server_default="0"),
        sa.Column("chunk_hits", sa.Integer(), nullable=False, server_default="0"),
        sa.Column("deflected", sa.Boolean(), nullable=False, server_default=sa.false()),
        sa.Column("sources", sa.Text(), nullable=False, server_default=""),
        sa.Column("latency_ms", sa.Integer(), nullable=False, server_default="0"),
        sa.Column(
            "created_at",
            sa.DateTime(timezone=True),
            server_default=sa.func.now(),
            nullable=False,
        ),
    )
    op.create_index("ix_query_log_created_at", "query_log", ["created_at"])


def downgrade() -> None:
    op.drop_table("query_log")
    op.drop_table("chunks")
    op.drop_table("documents")
    op.execute("DROP EXTENSION IF EXISTS vector")