"""add symbol index tables

Revision ID: add_symbol_index_tables
Revises: add_kg_sync_runs
Create Date: 2026-03-04
"""

from __future__ import annotations

from alembic import op
import sqlalchemy as sa

try:
    from sqlalchemy.dialects.postgresql import JSONB
except Exception:  # pragma: no cover
    JSONB = sa.JSON


# revision identifiers, used by Alembic.
revision = "add_symbol_index_tables"
down_revision = "add_kg_sync_runs"
branch_labels = None
depends_on = None


def _json_type(bind):
    return JSONB() if bind.dialect.name == "postgresql" else sa.JSON()


def _table_exists(bind, table_name: str) -> bool:
    inspector = sa.inspect(bind)
    return inspector.has_table(table_name)


def _index_exists(bind, table_name: str, index_name: str) -> bool:
    inspector = sa.inspect(bind)
    indexes = inspector.get_indexes(table_name)
    return any(idx.get("name") == index_name for idx in indexes)


def _create_index_if_not_exists(bind, index_name: str, table_name: str, columns: list[str]) -> None:
    if not _index_exists(bind, table_name, index_name):
        op.create_index(index_name, table_name, columns)


def _drop_index_if_exists(bind, index_name: str, table_name: str) -> None:
    if _index_exists(bind, table_name, index_name):
        op.drop_index(index_name, table_name=table_name)


def upgrade() -> None:
    bind = op.get_bind()

    if not _table_exists(bind, "symbol_definitions"):
        op.create_table(
            "symbol_definitions",
            sa.Column("id", sa.Integer(), primary_key=True, autoincrement=True),
            sa.Column("tenant_id", sa.BigInteger(), nullable=False, server_default="1"),
            sa.Column("created_at", sa.TIMESTAMP(), nullable=False, server_default=sa.func.now()),
            sa.Column("updated_at", sa.TIMESTAMP(), nullable=False, server_default=sa.func.now(), onupdate=sa.func.now()),
            sa.Column("file_path", sa.String(length=600), nullable=False),
            sa.Column("language", sa.String(length=20), nullable=False),
            sa.Column("symbol_type", sa.String(length=32), nullable=False),
            sa.Column("symbol_name", sa.String(length=255), nullable=False),
            sa.Column("qualified_name", sa.String(length=700), nullable=True),
            sa.Column("start_line", sa.Integer(), nullable=True),
            sa.Column("end_line", sa.Integer(), nullable=True),
            sa.Column("signature", sa.String(length=1000), nullable=True),
            sa.Column("docstring", sa.String(length=2000), nullable=True),
            sa.Column("file_hash", sa.String(length=64), nullable=True),
            sa.Column("source_mtime", sa.TIMESTAMP(), nullable=True),
            sa.Column("status", sa.String(length=20), nullable=False, server_default="active"),
            sa.Column("payload", _json_type(bind), nullable=True),
            sa.Column("last_indexed_at", sa.TIMESTAMP(), nullable=False, server_default=sa.func.now()),
            sa.UniqueConstraint(
                "tenant_id",
                "file_path",
                "symbol_type",
                "symbol_name",
                "start_line",
                name="uq_symbol_definitions_tenant_file_type_name_line",
            ),
        )

    _create_index_if_not_exists(bind, "ix_symbol_definitions_tenant_id", "symbol_definitions", ["tenant_id"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_file_path", "symbol_definitions", ["file_path"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_language", "symbol_definitions", ["language"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_symbol_type", "symbol_definitions", ["symbol_type"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_symbol_name", "symbol_definitions", ["symbol_name"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_qualified_name", "symbol_definitions", ["qualified_name"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_start_line", "symbol_definitions", ["start_line"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_file_hash", "symbol_definitions", ["file_hash"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_status", "symbol_definitions", ["status"])
    _create_index_if_not_exists(bind, "ix_symbol_definitions_last_indexed_at", "symbol_definitions", ["last_indexed_at"])

    if not _table_exists(bind, "symbol_references"):
        op.create_table(
            "symbol_references",
            sa.Column("id", sa.Integer(), primary_key=True, autoincrement=True),
            sa.Column("tenant_id", sa.BigInteger(), nullable=False, server_default="1"),
            sa.Column("created_at", sa.TIMESTAMP(), nullable=False, server_default=sa.func.now()),
            sa.Column("updated_at", sa.TIMESTAMP(), nullable=False, server_default=sa.func.now(), onupdate=sa.func.now()),
            sa.Column("source_symbol_id", sa.Integer(), sa.ForeignKey("symbol_definitions.id", ondelete="CASCADE"), nullable=True),
            sa.Column("file_path", sa.String(length=600), nullable=False),
            sa.Column("relation_type", sa.String(length=32), nullable=False),
            sa.Column("target_symbol_name", sa.String(length=255), nullable=False),
            sa.Column("target_qualified_name", sa.String(length=700), nullable=True),
            sa.Column("start_line", sa.Integer(), nullable=True),
            sa.Column("end_line", sa.Integer(), nullable=True),
            sa.Column("payload", _json_type(bind), nullable=True),
            sa.UniqueConstraint(
                "tenant_id",
                "file_path",
                "relation_type",
                "target_symbol_name",
                "start_line",
                "source_symbol_id",
                name="uq_symbol_references_tenant_file_relation_target_line_source",
            ),
        )

    _create_index_if_not_exists(bind, "ix_symbol_references_tenant_id", "symbol_references", ["tenant_id"])
    _create_index_if_not_exists(bind, "ix_symbol_references_source_symbol_id", "symbol_references", ["source_symbol_id"])
    _create_index_if_not_exists(bind, "ix_symbol_references_file_path", "symbol_references", ["file_path"])
    _create_index_if_not_exists(bind, "ix_symbol_references_relation_type", "symbol_references", ["relation_type"])
    _create_index_if_not_exists(bind, "ix_symbol_references_target_symbol_name", "symbol_references", ["target_symbol_name"])
    _create_index_if_not_exists(bind, "ix_symbol_references_target_qualified_name", "symbol_references", ["target_qualified_name"])
    _create_index_if_not_exists(bind, "ix_symbol_references_start_line", "symbol_references", ["start_line"])


def downgrade() -> None:
    bind = op.get_bind()

    if _table_exists(bind, "symbol_references"):
        _drop_index_if_exists(bind, "ix_symbol_references_start_line", "symbol_references")
        _drop_index_if_exists(bind, "ix_symbol_references_target_qualified_name", "symbol_references")
        _drop_index_if_exists(bind, "ix_symbol_references_target_symbol_name", "symbol_references")
        _drop_index_if_exists(bind, "ix_symbol_references_relation_type", "symbol_references")
        _drop_index_if_exists(bind, "ix_symbol_references_file_path", "symbol_references")
        _drop_index_if_exists(bind, "ix_symbol_references_source_symbol_id", "symbol_references")
        _drop_index_if_exists(bind, "ix_symbol_references_tenant_id", "symbol_references")
        op.drop_table("symbol_references")

    if _table_exists(bind, "symbol_definitions"):
        _drop_index_if_exists(bind, "ix_symbol_definitions_last_indexed_at", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_status", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_file_hash", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_start_line", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_qualified_name", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_symbol_name", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_symbol_type", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_language", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_file_path", "symbol_definitions")
        _drop_index_if_exists(bind, "ix_symbol_definitions_tenant_id", "symbol_definitions")
        op.drop_table("symbol_definitions")