use crate::{ColumnTrait, EntityTrait, Iterable, QueryFilter, QueryOrder, QuerySelect, QueryTrait};
use core::fmt::Debug;
use core::marker::PhantomData;
use sea_query::{Expr, IntoColumnRef, SelectStatement, SimpleExpr};
#[derive(Clone, Debug)]
pub struct Select<E>
where
E: EntityTrait,
{
pub(crate) query: SelectStatement,
pub(crate) entity: PhantomData<E>,
}
#[derive(Clone, Debug)]
pub struct SelectTwo<E, F>
where
E: EntityTrait,
F: EntityTrait,
{
pub(crate) query: SelectStatement,
pub(crate) entity: PhantomData<(E, F)>,
}
#[derive(Clone, Debug)]
pub struct SelectTwoMany<E, F>
where
E: EntityTrait,
F: EntityTrait,
{
pub(crate) query: SelectStatement,
pub(crate) entity: PhantomData<(E, F)>,
}
pub trait IntoSimpleExpr {
fn into_simple_expr(self) -> SimpleExpr;
}
macro_rules! impl_trait {
( $trait: ident ) => {
impl<E> $trait for Select<E>
where
E: EntityTrait,
{
type QueryStatement = SelectStatement;
fn query(&mut self) -> &mut SelectStatement {
&mut self.query
}
}
impl<E, F> $trait for SelectTwo<E, F>
where
E: EntityTrait,
F: EntityTrait,
{
type QueryStatement = SelectStatement;
fn query(&mut self) -> &mut SelectStatement {
&mut self.query
}
}
impl<E, F> $trait for SelectTwoMany<E, F>
where
E: EntityTrait,
F: EntityTrait,
{
type QueryStatement = SelectStatement;
fn query(&mut self) -> &mut SelectStatement {
&mut self.query
}
}
};
}
impl_trait!(QuerySelect);
impl_trait!(QueryFilter);
impl_trait!(QueryOrder);
impl<C> IntoSimpleExpr for C
where
C: ColumnTrait,
{
fn into_simple_expr(self) -> SimpleExpr {
SimpleExpr::Column(self.as_column_ref().into_column_ref())
}
}
impl IntoSimpleExpr for Expr {
fn into_simple_expr(self) -> SimpleExpr {
self.into()
}
}
impl IntoSimpleExpr for SimpleExpr {
fn into_simple_expr(self) -> SimpleExpr {
self
}
}
impl<E> Select<E>
where
E: EntityTrait,
{
pub(crate) fn new() -> Self {
Self {
query: SelectStatement::new(),
entity: PhantomData,
}
.prepare_select()
.prepare_from()
}
fn prepare_select(mut self) -> Self {
self.query.exprs(self.column_list());
self
}
fn column_list(&self) -> Vec<SimpleExpr> {
E::Column::iter()
.map(|col| col.select_as(col.into_expr()))
.collect()
}
fn prepare_from(mut self) -> Self {
self.query.from(E::default().table_ref());
self
}
}
impl<E> QueryTrait for Select<E>
where
E: EntityTrait,
{
type QueryStatement = SelectStatement;
fn query(&mut self) -> &mut SelectStatement {
&mut self.query
}
fn as_query(&self) -> &SelectStatement {
&self.query
}
fn into_query(self) -> SelectStatement {
self.query
}
}
macro_rules! select_two {
( $selector: ident ) => {
impl<E, F> QueryTrait for $selector<E, F>
where
E: EntityTrait,
F: EntityTrait,
{
type QueryStatement = SelectStatement;
fn query(&mut self) -> &mut SelectStatement {
&mut self.query
}
fn as_query(&self) -> &SelectStatement {
&self.query
}
fn into_query(self) -> SelectStatement {
self.query
}
}
};
}
select_two!(SelectTwo);
select_two!(SelectTwoMany);