use std::fmt::{Result, Write};
use super::*;
fn render_simple_pair(w: &mut impl Write, l: &SimpleExpr, op: &'static str, r: &SimpleExpr) -> Result {
w.write_char('(')?;
render_simple_expr(w, l)?;
w.write_char(' ')?;
w.write_str(op)?;
w.write_char(' ')?;
render_simple_expr(w, r)?;
w.write_char(')')
}
fn render_unary_function(w: &mut impl Write, f: &str, e: &SimpleExpr) -> Result {
w.write_str(f)?;
w.write_char('(')?;
render_simple_expr(w, e)?;
w.write_char(')')
}
fn render_index(w: &mut impl Write, e: &Index, with_dot: bool) -> Result {
match e {
Index::String(s) => {
if is_ident(s) {
if with_dot {
w.write_char('.')?;
}
w.write_str(s)
} else {
w.write_char('[')?;
render_string(w, s)?;
w.write_char(']')
}
}
Index::Number(n) => write!(w, "[{}]", n),
Index::Expr(e) => write!(w, "[({})]", e),
}
}
fn render_indexing(w: &mut impl Write, e: &Ind) -> Result {
if let SimpleExpr::Variable(v) = &*e.head {
w.write_str(v)?;
} else {
w.write_char('(')?;
render_simple_expr(w, &e.head)?;
w.write_char(')')?;
}
for t in e.tail.iter() {
render_index(w, t, true)?;
}
Ok(())
}
pub fn render_number(w: &mut impl Write, e: &Num) -> Result {
match e {
Num::Decimal(d) => write!(w, "{}", d),
Num::Natural(n) => write!(w, "{}", n),
}
}
fn render_object(w: &mut impl Write, e: &Obj) -> Result {
w.write_str("{ ")?;
for (i, (k, v)) in e.props.iter().enumerate() {
if i > 0 {
w.write_str(", ")?;
}
render_index(w, k, false)?;
w.write_str(": ")?;
render_simple_expr(w, v)?;
}
w.write_str(" }")
}
fn render_array(w: &mut impl Write, e: &Arr) -> Result {
w.write_char('[')?;
for (i, x) in e.items.iter().enumerate() {
if i > 0 {
w.write_str(", ")?;
}
render_simple_expr(w, x)?;
}
w.write_char(']')
}
pub(crate) fn render_string(w: &mut impl Write, e: &str) -> Result {
w.write_char('\'')?;
w.write_str(&e.replace('\'', "''"))?;
w.write_char('\'')
}
pub fn render_simple_expr(w: &mut impl Write, e: &SimpleExpr) -> Result {
match e {
SimpleExpr::Variable(v) => w.write_str(v),
SimpleExpr::Indexing(i) => render_indexing(w, i),
SimpleExpr::Number(n) => render_number(w, n),
SimpleExpr::String(s) => render_string(w, s),
SimpleExpr::Object(o) => render_object(w, o),
SimpleExpr::Array(a) => render_array(w, a),
SimpleExpr::Null => w.write_str("NULL"),
SimpleExpr::Bool(b) => {
if *b {
w.write_str("TRUE")
} else {
w.write_str("FALSE")
}
}
SimpleExpr::Not(e) => {
w.write_char('!')?;
render_simple_expr(w, e)
}
SimpleExpr::Cases(v) => {
for (pred, expr) in v.iter() {
w.write_str("CASE ")?;
render_simple_expr(w, pred)?;
w.write_str(" => ")?;
render_simple_expr(w, expr)?;
w.write_char(' ')?;
}
w.write_str("ENDCASE")
}
SimpleExpr::BinOp(e) => render_simple_pair(w, &e.1, e.0.as_str(), &e.2),
SimpleExpr::AggrOp(e) => render_unary_function(w, e.0.as_str(), &e.1),
SimpleExpr::FuncCall(f) => {
w.write_str(&f.name)?;
w.write_char('(')?;
for (idx, expr) in f.args.iter().enumerate() {
if idx > 0 {
w.write_str(", ")?;
}
render_simple_expr(w, expr)?;
}
w.write_char(')')
}
}
}
fn render_operation(w: &mut impl Write, e: &Operation) -> Result {
match e {
Operation::Filter(f) => {
w.write_str("FILTER ")?;
render_simple_expr(w, f)
}
Operation::Select(s) => {
w.write_str("SELECT ")?;
let mut first = true;
for e in s.iter() {
if first {
first = false;
} else {
w.write_str(", ")?;
}
render_simple_expr(w, e)?;
}
Ok(())
}
Operation::Aggregate(a) => {
w.write_str("AGGREGATE ")?;
render_simple_expr(w, a)
}
}
}
pub fn render_tag_expr(w: &mut impl Write, e: &TagExpr, _parent: Option<&TagExpr>) -> Result {
match e {
TagExpr::Or(or) => {
w.write_char('(')?;
render_tag_expr(w, &or.0, Some(e))?;
w.write_str(" | ")?;
render_tag_expr(w, &or.1, Some(e))?;
w.write_char(')')
}
TagExpr::And(and) => {
w.write_char('(')?;
render_tag_expr(w, &and.0, Some(e))?;
w.write_str(" & ")?;
render_tag_expr(w, &and.1, Some(e))?;
w.write_char(')')
}
TagExpr::Atom(atom) => render_tag_atom(w, atom),
}
}
fn render_timestamp(w: &mut impl Write, e: Timestamp) -> Result {
use chrono::prelude::*;
let dt: DateTime<Utc> = e.into();
let str = if dt.hour() == 0 && dt.minute() == 0 && dt.second() == 0 && dt.nanosecond() == 0 {
dt.format("%Y-%m-%dZ").to_string()
} else {
dt.to_rfc3339_opts(SecondsFormat::AutoSi, true)
};
w.write_str(&str)
}
fn render_tag_atom(w: &mut impl Write, e: &TagAtom) -> Result {
match e {
TagAtom::Tag(t) => render_string(w, &t.to_string()),
TagAtom::AllEvents => w.write_str("allEvents"),
TagAtom::IsLocal => w.write_str("isLocal"),
TagAtom::FromTime(ft) => {
w.write_str("from(")?;
render_timestamp(w, *ft)?;
w.write_char(')')
}
TagAtom::ToTime(tt) => {
w.write_str("to(")?;
render_timestamp(w, *tt)?;
w.write_char(')')
}
TagAtom::FromLamport(SortKey { lamport, stream }) => {
w.write_str("from(")?;
write!(w, "{}/{}", u64::from(*lamport), stream)?;
w.write_char(')')
}
TagAtom::ToLamport(SortKey { lamport, stream }) => {
w.write_str("to(")?;
write!(w, "{}/{}", u64::from(*lamport), stream)?;
w.write_char(')')
}
TagAtom::AppId(app_id) => w.write_fmt(format_args!("appId({})", app_id)),
}
}
pub fn render_query(w: &mut impl Write, e: &Query) -> Result {
if !e.features.is_empty() {
w.write_str("FEATURES(")?;
for (i, f) in e.features.iter().enumerate() {
if i > 0 {
w.write_char(' ')?;
}
w.write_str(f)?;
}
w.write_str(") ")?;
}
w.write_str("FROM ")?;
render_tag_expr(w, &e.from, None)?;
for op in &e.ops {
w.write_char(' ')?;
render_operation(w, op)?;
}
w.write_str(" END")
}