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use crate::decode::Decode;
use crate::encode::{Encode, IsNull};
use crate::error::BoxDynError;
use crate::postgres::{
PgArgumentBuffer, PgHasArrayType, PgTypeInfo, PgValueFormat, PgValueRef, Postgres,
};
use crate::types::Type;
use std::fmt::{self, Display, Formatter};
use std::io::Write;
use std::ops::Deref;
use std::str::FromStr;
#[derive(Debug, thiserror::Error)]
#[non_exhaustive]
pub enum PgLTreeParseError {
#[error("ltree label contains invalid characters")]
InvalidLtreeLabel,
#[error("ltree version not supported")]
InvalidLtreeVersion,
}
#[derive(Clone, Debug, Default, PartialEq)]
pub struct PgLTreeLabel(String);
impl PgLTreeLabel {
pub fn new<S>(label: S) -> Result<Self, PgLTreeParseError>
where
String: From<S>,
{
let label = String::from(label);
if label.len() <= 256
&& label
.bytes()
.all(|c| c.is_ascii_alphabetic() || c.is_ascii_digit() || c == b'_')
{
Ok(Self(label))
} else {
Err(PgLTreeParseError::InvalidLtreeLabel)
}
}
}
impl Deref for PgLTreeLabel {
type Target = str;
fn deref(&self) -> &Self::Target {
self.0.as_str()
}
}
impl FromStr for PgLTreeLabel {
type Err = PgLTreeParseError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
PgLTreeLabel::new(s)
}
}
impl Display for PgLTreeLabel {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.0)
}
}
#[derive(Clone, Debug, Default, PartialEq)]
pub struct PgLTree {
labels: Vec<PgLTreeLabel>,
}
impl PgLTree {
pub fn new() -> Self {
Self::default()
}
pub fn from(labels: Vec<PgLTreeLabel>) -> Self {
Self { labels }
}
pub fn from_iter<I, S>(labels: I) -> Result<Self, PgLTreeParseError>
where
String: From<S>,
I: IntoIterator<Item = S>,
{
let mut ltree = Self::default();
for label in labels {
ltree.push(PgLTreeLabel::new(label)?);
}
Ok(ltree)
}
pub fn push(&mut self, label: PgLTreeLabel) {
self.labels.push(label);
}
pub fn pop(&mut self) -> Option<PgLTreeLabel> {
self.labels.pop()
}
}
impl IntoIterator for PgLTree {
type Item = PgLTreeLabel;
type IntoIter = std::vec::IntoIter<Self::Item>;
fn into_iter(self) -> Self::IntoIter {
self.labels.into_iter()
}
}
impl FromStr for PgLTree {
type Err = PgLTreeParseError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
Ok(Self {
labels: s
.split('.')
.map(|s| PgLTreeLabel::new(s))
.collect::<Result<Vec<_>, Self::Err>>()?,
})
}
}
impl Display for PgLTree {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
let mut iter = self.labels.iter();
if let Some(label) = iter.next() {
write!(f, "{}", label)?;
for label in iter {
write!(f, ".{}", label)?;
}
}
Ok(())
}
}
impl Deref for PgLTree {
type Target = [PgLTreeLabel];
fn deref(&self) -> &Self::Target {
&self.labels
}
}
impl Type<Postgres> for PgLTree {
fn type_info() -> PgTypeInfo {
PgTypeInfo::with_name("ltree")
}
}
impl PgHasArrayType for PgLTree {
fn array_type_info() -> PgTypeInfo {
PgTypeInfo::with_name("_ltree")
}
}
impl Encode<'_, Postgres> for PgLTree {
fn encode_by_ref(&self, buf: &mut PgArgumentBuffer) -> IsNull {
buf.extend(1i8.to_le_bytes());
write!(buf, "{}", self)
.expect("Display implementation panicked while writing to PgArgumentBuffer");
IsNull::No
}
}
impl<'r> Decode<'r, Postgres> for PgLTree {
fn decode(value: PgValueRef<'r>) -> Result<Self, BoxDynError> {
match value.format() {
PgValueFormat::Binary => {
let bytes = value.as_bytes()?;
let version = i8::from_le_bytes([bytes[0]; 1]);
if version != 1 {
return Err(Box::new(PgLTreeParseError::InvalidLtreeVersion));
}
Ok(Self::from_str(std::str::from_utf8(&bytes[1..])?)?)
}
PgValueFormat::Text => Ok(Self::from_str(value.as_str()?)?),
}
}
}