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use {
	crate::{ExecuteError, JoinError, Result, Value},
	serde::Serialize,
	sqlparser::ast::{ObjectName as AstObjectName, TableFactor},
	std::fmt::Debug,
};

pub type Alias = Option<String>;
pub type Label = String;
pub type Row = Vec<Value>;
pub type LabelsAndRows = (Vec<Label>, Vec<Row>);
pub type ObjectName = Vec<String>;

#[derive(Debug, Clone)]
pub struct ColumnInfo {
	pub table: ComplexTableName,
	pub name: String,
	pub index: Option<String>,
}

pub(crate) fn get_first_name(names: &[AstObjectName]) -> Result<String> {
	names
		.get(0)
		.and_then(|name| name.0.get(0).map(|name| name.value.clone()))
		.ok_or(ExecuteError::ObjectNotRecognised.into())
}

#[derive(Debug, Clone, PartialEq, Serialize)]
pub struct ComplexTableName {
	pub database: Option<String>,
	pub alias: Alias,
	pub name: String,
}
impl TryFrom<&AstObjectName> for ComplexTableName {
	type Error = crate::Error;
	fn try_from(name: &AstObjectName) -> Result<Self> {
		let name_parts = name.0.len();
		if !(1..=2).contains(&name_parts) {
			return Err(JoinError::UnimplementedNumberOfComponents.into());
		}
		let database = if name_parts == 2 {
			Some(name.0.get(0).unwrap().value.clone())
		} else {
			None
		};
		let name = name.0.last().unwrap().value.clone();
		Ok(Self {
			database,
			name,
			alias: None,
		})
	}
}
impl TryFrom<TableFactor> for ComplexTableName {
	type Error = crate::Error;
	fn try_from(table: TableFactor) -> Result<Self> {
		match table {
			TableFactor::Table { name, alias, .. } => {
				let name_parts = name.0.len();
				if !(1..=2).contains(&name_parts) {
					return Err(JoinError::UnimplementedNumberOfComponents.into());
				}
				let database = if name_parts == 2 {
					Some(name.0.get(0).unwrap().value.clone())
				} else {
					None
				};
				let name = name.0.last().unwrap().value.clone();
				let alias = alias.map(|alias| alias.name.value);
				Ok(Self {
					database,
					name,
					alias,
				})
			}
			_ => Err(JoinError::UnimplementedTableType.into()),
		}
	}
}

impl ColumnInfo {
	pub fn of_name(name: String) -> Self {
		ColumnInfo {
			table: ComplexTableName {
				database: None,
				name: String::new(),
				alias: None,
			},
			name,
			index: None,
		}
	}
}

impl PartialEq<ObjectName> for ColumnInfo {
	fn eq(&self, other: &ObjectName) -> bool {
		let mut other = other.clone();
		other.reverse();
		let names_eq = other
			.get(0)
			.map(|column| column == &self.name)
			.unwrap_or(false);
		let tables_eq = other
			.get(1)
			.map(|table| {
				table == &self.table.name
					|| self
						.table
						.alias
						.as_ref()
						.map(|alias| table == alias)
						.unwrap_or(false)
			})
			.unwrap_or(true);
		names_eq && tables_eq
	}
}