use crate::idx::ft::MatchRef;
use crate::sql::index::Distance;
use revision::revisioned;
use serde::{Deserialize, Serialize};
use std::fmt;
use std::fmt::Write;

/// Binary operators.
#[revisioned(revision = 2)]
#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Serialize, Deserialize, Hash)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
#[non_exhaustive]
pub enum Operator {
	//
	Neg, // -
	Not, // !
	//
	Or,  // ||
	And, // &&
	Tco, // ?: Ternary conditional operator
	Nco, // ?? Null coalescing operator
	//
	Add, // +
	Sub, // -
	Mul, // *
	Div, // /
	Pow, // **
	Inc, // +=
	Dec, // -=
	Ext, // +?=
	//
	Equal,    // =
	Exact,    // ==
	NotEqual, // !=
	AllEqual, // *=
	AnyEqual, // ?=
	//
	Like,                      // ~
	NotLike,                   // !~
	AllLike,                   // *~
	AnyLike,                   // ?~
	Matches(Option<MatchRef>), // @{ref}@
	//
	LessThan,        // <
	LessThanOrEqual, // <=
	MoreThan,        // >
	MoreThanOrEqual, // >=
	//
	Contain,     // ∋
	NotContain,  // ∌
	ContainAll,  // ⊇
	ContainAny,  // ⊃
	ContainNone, // ⊅
	Inside,      // ∈
	NotInside,   // ∉
	AllInside,   // ⊆
	AnyInside,   // ⊂
	NoneInside,  // ⊄
	//
	Outside,
	Intersects,
	//
	Knn(u32, Option<Distance>), // <|{k}[,{dist}]|>
	#[revision(start = 2)]
	Ann(u32, u32), // <|{k},{ef}|>
	//
	Rem, // %
}

impl Default for Operator {
	fn default() -> Self {
		Self::Equal
	}
}

impl Operator {
	#[inline]
	pub fn precedence(&self) -> u8 {
		match self {
			Self::Or => 1,
			Self::And => 2,
			Self::Tco => 3,
			Self::Nco => 4,
			Self::Sub => 6,
			Self::Add => 7,
			Self::Mul => 8,
			Self::Div => 9,
			Self::Rem => 10,
			_ => 5,
		}
	}
}

impl fmt::Display for Operator {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		match self {
			Self::Neg => f.write_str("-"),
			Self::Not => f.write_str("!"),
			Self::Or => f.write_str("OR"),
			Self::And => f.write_str("AND"),
			Self::Tco => f.write_str("?:"),
			Self::Nco => f.write_str("??"),
			Self::Add => f.write_str("+"),
			Self::Sub => f.write_char('-'),
			Self::Mul => f.write_char('*'),
			Self::Div => f.write_char('/'),
			Self::Rem => f.write_char('%'),
			Self::Pow => f.write_str("**"),
			Self::Inc => f.write_str("+="),
			Self::Dec => f.write_str("-="),
			Self::Ext => f.write_str("+?="),
			Self::Equal => f.write_char('='),
			Self::Exact => f.write_str("=="),
			Self::NotEqual => f.write_str("!="),
			Self::AllEqual => f.write_str("*="),
			Self::AnyEqual => f.write_str("?="),
			Self::Like => f.write_char('~'),
			Self::NotLike => f.write_str("!~"),
			Self::AllLike => f.write_str("*~"),
			Self::AnyLike => f.write_str("?~"),
			Self::LessThan => f.write_char('<'),
			Self::LessThanOrEqual => f.write_str("<="),
			Self::MoreThan => f.write_char('>'),
			Self::MoreThanOrEqual => f.write_str(">="),
			Self::Contain => f.write_str("CONTAINS"),
			Self::NotContain => f.write_str("CONTAINSNOT"),
			Self::ContainAll => f.write_str("CONTAINSALL"),
			Self::ContainAny => f.write_str("CONTAINSANY"),
			Self::ContainNone => f.write_str("CONTAINSNONE"),
			Self::Inside => f.write_str("INSIDE"),
			Self::NotInside => f.write_str("NOTINSIDE"),
			Self::AllInside => f.write_str("ALLINSIDE"),
			Self::AnyInside => f.write_str("ANYINSIDE"),
			Self::NoneInside => f.write_str("NONEINSIDE"),
			Self::Outside => f.write_str("OUTSIDE"),
			Self::Intersects => f.write_str("INTERSECTS"),
			Self::Matches(reference) => {
				if let Some(r) = reference {
					write!(f, "@{r}@")
				} else {
					f.write_str("@@")
				}
			}
			Self::Knn(k, dist) => {
				if let Some(d) = dist {
					write!(f, "<|{k},{d}|>")
				} else {
					write!(f, "<|{k}|>")
				}
			}
			Self::Ann(k, ef) => {
				write!(f, "<{k},{ef}>")
			}
		}
	}
}