"""Add source, document, review and audit management."""

import sqlalchemy as sa
from alembic import op

revision = "0002_catalog"
down_revision = "0001_baseline"
branch_labels = None
depends_on = None


def version_columns():
    return [
        sa.Column("version", sa.Integer(), server_default="1", nullable=False),
        sa.Column(
            "created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False
        ),
        sa.Column(
            "updated_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False
        ),
        sa.Column("is_deleted", sa.Boolean(), server_default=sa.false(), nullable=False),
    ]


def upgrade():
    op.create_table(
        "sources",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column("name", sa.String(250), nullable=False),
        sa.Column("source_url", sa.String(1000)),
        sa.Column("notes", sa.Text(), nullable=False),
        *version_columns(),
    )
    op.create_table(
        "documents",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column("source_id", sa.Integer(), sa.ForeignKey("sources.id"), nullable=False),
        sa.Column("title", sa.String(250), nullable=False),
        sa.Column("category", sa.String(80), nullable=False),
        sa.Column("content", sa.Text(), nullable=False),
        sa.Column("collected_at", sa.DateTime(timezone=True), nullable=False),
        sa.Column("notes", sa.Text(), nullable=False),
        *version_columns(),
    )
    op.create_index("ix_documents_source_id", "documents", ["source_id"])
    op.create_table(
        "audit_events",
        sa.Column("id", sa.Integer(), primary_key=True),
        sa.Column("entity_type", sa.String(30), nullable=False),
        sa.Column("entity_id", sa.Integer(), nullable=False),
        sa.Column("action", sa.String(30), nullable=False),
        sa.Column("actor", sa.String(100)),
        sa.Column("notes", sa.Text(), nullable=False),
        sa.Column("snapshot", sa.JSON(), nullable=False),
        sa.Column(
            "created_at", sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False
        ),
    )
    op.create_index("ix_audit_events_entity_type", "audit_events", ["entity_type"])
    op.create_index("ix_audit_events_entity_id", "audit_events", ["entity_id"])
    for column in version_columns():
        if column.name != "created_at":
            op.add_column("knowledge_items", column)
    for name, kind in [
        ("source_id", sa.Integer()),
        ("document_id", sa.Integer()),
        ("collected_at", sa.DateTime(timezone=True)),
        ("reviewer", sa.String(100)),
        ("reviewed_at", sa.DateTime(timezone=True)),
        ("verification_notes", sa.Text()),
    ]:
        op.add_column("knowledge_items", sa.Column(name, kind))
    for name, parent in [("source_id", "sources"), ("document_id", "documents")]:
        op.create_foreign_key(f"fk_knowledge_{name}", "knowledge_items", parent, [name], ["id"])
        op.create_index(f"ix_knowledge_items_{name}", "knowledge_items", [name])
    op.create_check_constraint(
        "ck_knowledge_verification_status",
        "knowledge_items",
        "verification_status IN ('pending', 'verified', 'rejected')",
    )
    op.execute("""INSERT INTO audit_events (entity_type, entity_id, action, notes, snapshot)
        SELECT 'knowledge_items', id, 'import', '保留基础版本数据及原状态',
               json_build_object('item', row_to_json(k)) FROM knowledge_items k""")
    op.execute("""UPDATE knowledge_items SET verification_status = 'pending', version = version + 1
        WHERE verification_status = 'verified'""")
    op.execute("""INSERT INTO audit_events (entity_type, entity_id, action, notes, snapshot)
        SELECT 'knowledge_items', id, 'invalidate', '旧版本没有完整审核记录，需要重新核验',
               json_build_object('item', row_to_json(k)) FROM knowledge_items k WHERE version = 2""")


def downgrade():
    op.drop_constraint("ck_knowledge_verification_status", "knowledge_items", type_="check")
    for name in ["source_id", "document_id"]:
        op.drop_index(f"ix_knowledge_items_{name}", table_name="knowledge_items")
        op.drop_constraint(f"fk_knowledge_{name}", "knowledge_items", type_="foreignkey")
    for name in [
        "source_id",
        "document_id",
        "collected_at",
        "reviewer",
        "reviewed_at",
        "verification_notes",
        "version",
        "updated_at",
        "is_deleted",
    ]:
        op.drop_column("knowledge_items", name)
    op.drop_table("audit_events")
    op.drop_table("documents")
    op.drop_table("sources")