use async_trait::async_trait;
use drasi_query_ast::ast;
use crate::evaluation::functions::ScalarFunction;
use crate::evaluation::variable_value::float::Float;
use crate::evaluation::variable_value::VariableValue;
use crate::evaluation::{ExpressionEvaluationContext, FunctionError, FunctionEvaluationError};
#[derive(Debug)]
pub struct Floor {}
#[async_trait]
impl ScalarFunction for Floor {
async fn call(
&self,
_context: &ExpressionEvaluationContext,
expression: &ast::FunctionExpression,
args: Vec<VariableValue>,
) -> Result<VariableValue, FunctionError> {
if args.len() != 1 {
return Err(FunctionError {
function_name: expression.name.to_string(),
error: FunctionEvaluationError::InvalidArgumentCount,
});
}
match &args[0] {
VariableValue::Null => Ok(VariableValue::Null),
VariableValue::Integer(n) => {
Ok(VariableValue::Float(
match Float::from_f64(match n.as_i64() {
Some(i) => i as f64,
None => {
return Err(FunctionError {
function_name: expression.name.to_string(),
error: FunctionEvaluationError::OverflowError,
})
}
}) {
Some(f) => f,
None => {
return Err(FunctionError {
function_name: expression.name.to_string(),
error: FunctionEvaluationError::OverflowError,
})
}
},
)) }
VariableValue::Float(n) => Ok(VariableValue::Float(
match Float::from_f64(match n.as_f64() {
Some(f) => f.floor(),
None => {
return Err(FunctionError {
function_name: expression.name.to_string(),
error: FunctionEvaluationError::OverflowError,
})
}
}) {
Some(f) => f,
None => {
return Err(FunctionError {
function_name: expression.name.to_string(),
error: FunctionEvaluationError::OverflowError,
})
}
},
)),
_ => Err(FunctionError {
function_name: expression.name.to_string(),
error: FunctionEvaluationError::InvalidArgument(0),
}),
}
}
}