use reifydb_core::value::column::{Column, columns::Columns, data::ColumnData};
use reifydb_type::value::{container::temporal::TemporalContainer, date::Date, r#type::Type};
use crate::function::{Function, FunctionCapability, FunctionContext, FunctionInfo, error::FunctionError};
pub struct DateTrunc {
info: FunctionInfo,
}
impl Default for DateTrunc {
fn default() -> Self {
Self::new()
}
}
impl DateTrunc {
pub fn new() -> Self {
Self {
info: FunctionInfo::new("date::trunc"),
}
}
}
impl Function for DateTrunc {
fn info(&self) -> &FunctionInfo {
&self.info
}
fn capabilities(&self) -> &[FunctionCapability] {
&[FunctionCapability::Scalar]
}
fn return_type(&self, _input_types: &[Type]) -> Type {
Type::Date
}
fn execute(&self, ctx: &FunctionContext, args: &Columns) -> Result<Columns, FunctionError> {
if args.len() != 2 {
return Err(FunctionError::ArityMismatch {
function: ctx.fragment.clone(),
expected: 2,
actual: args.len(),
});
}
let date_col = &args[0];
let prec_col = &args[1];
let (date_data, date_bitvec) = date_col.data().unwrap_option();
let (prec_data, prec_bitvec) = prec_col.data().unwrap_option();
let row_count = date_data.len();
let result_data = match (date_data, prec_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(FunctionError::ExecutionFailed {
function: ctx.fragment.clone(),
reason: format!("invalid precision: '{}'", other),
});
}
};
match truncated {
Some(val) => container.push(val),
None => container.push_default(),
}
}
_ => container.push_default(),
}
}
ColumnData::Date(container)
}
(ColumnData::Date(_), other) => {
return Err(FunctionError::InvalidArgumentType {
function: ctx.fragment.clone(),
argument_index: 1,
expected: vec![Type::Utf8],
actual: other.get_type(),
});
}
(other, _) => {
return Err(FunctionError::InvalidArgumentType {
function: ctx.fragment.clone(),
argument_index: 0,
expected: vec![Type::Date],
actual: other.get_type(),
});
}
};
let final_data = match (date_bitvec, prec_bitvec) {
(Some(bv), _) | (_, Some(bv)) => ColumnData::Option {
inner: Box::new(result_data),
bitvec: bv.clone(),
},
_ => result_data,
};
Ok(Columns::new(vec![Column::new(ctx.fragment.clone(), final_data)]))
}
}