use reifydb_core::value::column::data::ColumnData;
use reifydb_type::value::{container::temporal::TemporalContainer, date::Date, r#type::Type};
use crate::function::{
ScalarFunction, ScalarFunctionContext,
error::{ScalarFunctionError, ScalarFunctionResult},
propagate_options,
};
pub struct DateTrunc;
impl DateTrunc {
pub fn new() -> Self {
Self
}
}
impl ScalarFunction for DateTrunc {
fn scalar(&self, ctx: ScalarFunctionContext) -> ScalarFunctionResult<ColumnData> {
if let Some(result) = propagate_options(self, &ctx) {
return result;
}
let columns = ctx.columns;
let row_count = ctx.row_count;
if columns.len() != 2 {
return Err(ScalarFunctionError::ArityMismatch {
function: ctx.fragment.clone(),
expected: 2,
actual: columns.len(),
});
}
let date_col = columns.get(0).unwrap();
let prec_col = columns.get(1).unwrap();
match (date_col.data(), prec_col.data()) {
(
ColumnData::Date(date_container),
ColumnData::Utf8 {
container: prec_container,
..
},
) => {
let mut container = TemporalContainer::with_capacity(row_count);
for i in 0..row_count {
match (date_container.get(i), prec_container.is_defined(i)) {
(Some(d), true) => {
let precision = &prec_container[i];
let truncated =
match precision.as_str() {
"year" => Date::new(d.year(), 1, 1),
"month" => Date::new(d.year(), d.month(), 1),
other => {
return Err(ScalarFunctionError::ExecutionFailed {
function: ctx.fragment.clone(),
reason: format!("invalid precision: '{}'", other),
});
}
};
match truncated {
Some(val) => container.push(val),
None => container.push_default(),
}
}
_ => container.push_default(),
}
}
Ok(ColumnData::Date(container))
}
(ColumnData::Date(_), other) => Err(ScalarFunctionError::InvalidArgumentType {
function: ctx.fragment.clone(),
argument_index: 1,
expected: vec![Type::Utf8],
actual: other.get_type(),
}),
(other, _) => Err(ScalarFunctionError::InvalidArgumentType {
function: ctx.fragment.clone(),
argument_index: 0,
expected: vec![Type::Date],
actual: other.get_type(),
}),
}
}
fn return_type(&self, _input_types: &[Type]) -> Type {
Type::Date
}
}