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use {
    super::{join::JoinOperatorType, Prebuild},
    crate::{
        ast::{Query, Select, SelectItem, TableAlias, TableFactor, TableWithJoins},
        ast_builder::{
            table_factor::TableType, ExprList, ExprNode, FilterNode, GroupByNode, JoinNode,
            LimitNode, OffsetNode, OrderByExprList, OrderByNode, ProjectNode, QueryNode,
            SelectItemList, TableFactorNode,
        },
        result::Result,
        translate::alias_or_name,
    },
};

#[derive(Clone, Debug)]
pub struct SelectNode<'a> {
    table_node: TableFactorNode<'a>,
}

impl<'a> SelectNode<'a> {
    pub fn new(table_node: TableFactorNode<'a>) -> Self {
        Self { table_node }
    }

    pub fn filter<T: Into<ExprNode<'a>>>(self, expr: T) -> FilterNode<'a> {
        FilterNode::new(self, expr)
    }

    pub fn group_by<T: Into<ExprList<'a>>>(self, expr_list: T) -> GroupByNode<'a> {
        GroupByNode::new(self, expr_list)
    }

    pub fn offset<T: Into<ExprNode<'a>>>(self, expr: T) -> OffsetNode<'a> {
        OffsetNode::new(self, expr)
    }

    pub fn limit<T: Into<ExprNode<'a>>>(self, expr: T) -> LimitNode<'a> {
        LimitNode::new(self, expr)
    }

    pub fn project<T: Into<SelectItemList<'a>>>(self, select_items: T) -> ProjectNode<'a> {
        ProjectNode::new(self, select_items)
    }

    pub fn order_by<T: Into<OrderByExprList<'a>>>(self, order_by_exprs: T) -> OrderByNode<'a> {
        OrderByNode::new(self, order_by_exprs)
    }

    pub fn join(self, table_name: &str) -> JoinNode<'a> {
        JoinNode::new(self, table_name.to_owned(), None, JoinOperatorType::Inner)
    }

    pub fn join_as(self, table_name: &str, alias: &str) -> JoinNode<'a> {
        JoinNode::new(
            self,
            table_name.to_owned(),
            Some(alias.to_owned()),
            JoinOperatorType::Inner,
        )
    }

    pub fn left_join(self, table_name: &str) -> JoinNode<'a> {
        JoinNode::new(self, table_name.to_owned(), None, JoinOperatorType::Left)
    }

    pub fn left_join_as(self, table_name: &str, alias: &str) -> JoinNode<'a> {
        JoinNode::new(
            self,
            table_name.to_owned(),
            Some(alias.to_owned()),
            JoinOperatorType::Left,
        )
    }

    pub fn alias_as(self, table_alias: &'a str) -> TableFactorNode {
        QueryNode::SelectNode(self).alias_as(table_alias)
    }
}

impl<'a> Prebuild<Select> for SelectNode<'a> {
    fn prebuild(self) -> Result<Select> {
        let alias = self.table_node.table_alias.map(|name| TableAlias {
            name,
            columns: Vec::new(),
        });

        let relation = match self.table_node.table_type {
            TableType::Table => TableFactor::Table {
                name: self.table_node.table_name,
                alias,
                index: None,
            },
            TableType::Dictionary(dict) => TableFactor::Dictionary {
                dict,
                alias: alias_or_name(alias, self.table_node.table_name),
            },
            TableType::Series(args) => TableFactor::Series {
                alias: alias_or_name(alias, self.table_node.table_name),
                size: args.try_into()?,
            },
            TableType::Derived { subquery, alias } => TableFactor::Derived {
                subquery: Query::try_from(*subquery)?,
                alias: TableAlias {
                    name: alias,
                    columns: Vec::new(),
                },
            },
        };

        let from = TableWithJoins {
            relation,
            joins: Vec::new(),
        };

        Ok(Select {
            projection: vec![SelectItem::Wildcard],
            from,
            selection: None,
            group_by: Vec::new(),
            having: None,
        })
    }
}

#[cfg(test)]
mod tests {
    use crate::ast_builder::{table, test, Build};

    #[test]
    fn select() {
        // select node -> build
        let actual = table("App").select().build();
        let expected = "SELECT * FROM App";
        test(actual, expected);

        let actual = table("Item").alias_as("i").select().build();
        let expected = "SELECT * FROM Item i";
        test(actual, expected);

        // select -> derived subquery
        let actual = table("App").select().alias_as("Sub").select().build();
        let expected = "SELECT * FROM (SELECT * FROM App) Sub";
        test(actual, expected);
    }
}