use crate::backend::Backend;
use crate::expression::Expression;
use crate::query_builder::upsert::on_conflict_target::{ConflictTarget, NoConflictTarget};
use crate::query_builder::where_clause::{NoWhereClause, WhereAnd, WhereClause};
use crate::query_builder::{AstPass, QueryFragment, QueryResult};
use crate::sql_types::BoolOrNullableBool;
pub trait UndecoratedConflictTarget {}
impl UndecoratedConflictTarget for NoConflictTarget {}
impl<T> UndecoratedConflictTarget for ConflictTarget<T> {}
pub trait DecoratableTarget<P> {
type FilterOutput;
fn filter_target(self, predicate: P) -> Self::FilterOutput;
}
#[derive(Debug)]
pub struct DecoratedConflictTarget<T, U> {
pub(crate) target: T,
pub(crate) where_clause: U,
}
impl<T, P> DecoratableTarget<P> for T
where
P: Expression,
P::SqlType: BoolOrNullableBool,
T: UndecoratedConflictTarget,
{
type FilterOutput = DecoratedConflictTarget<T, WhereClause<P>>;
fn filter_target(self, predicate: P) -> Self::FilterOutput {
DecoratedConflictTarget {
target: self,
where_clause: NoWhereClause.and(predicate),
}
}
}
impl<T, U, P> DecoratableTarget<P> for DecoratedConflictTarget<T, U>
where
P: Expression,
P::SqlType: BoolOrNullableBool,
U: WhereAnd<P>,
{
type FilterOutput = DecoratedConflictTarget<T, <U as WhereAnd<P>>::Output>;
fn filter_target(self, predicate: P) -> Self::FilterOutput {
DecoratedConflictTarget {
target: self.target,
where_clause: self.where_clause.and(predicate),
}
}
}
impl<DB, T, U> QueryFragment<DB> for DecoratedConflictTarget<T, U>
where
DB: Backend,
Self: QueryFragment<DB, DB::OnConflictClause>,
{
fn walk_ast<'b>(&'b self, pass: AstPass<'_, 'b, DB>) -> QueryResult<()> {
<Self as QueryFragment<DB, DB::OnConflictClause>>::walk_ast(self, pass)
}
}