use crate::{
    expression::{BuiltinSelectionFn, ResultTransform, SearchModifier},
    selection::Selection,
    selection_functions::{
        function_character::selection_function_character,
        function_empty::selection_function_empty,
        function_end::selection_function_end,
        result_transformation::{complement_transform, conditional_transform},
    },
    state::EditorState,
};

mod function_character;
mod function_empty;
mod function_end;
mod result_transformation;
mod types;

pub use crate::selection_functions::types::{
    SelectionFunction, SelectionFunctionError, UnparameterisedSelectionFunction,
};

pub fn evaluate_selection_function(
    es: &EditorState,
    sf: BuiltinSelectionFn,
    search_mod: Option<SearchModifier>,
    result_transform: Option<ResultTransform>,
    left: Option<Selection>,
    right: Option<Selection>,
) -> Result<Selection, SelectionFunctionError> {
    let res = match sf {
        BuiltinSelectionFn::CharOffset(off) => {
            selection_function_character(off, es, left.as_ref(), right.as_ref(), search_mod)
        }
        BuiltinSelectionFn::Empty => {
            selection_function_empty(es, left.as_ref(), right.as_ref(), search_mod)
        }
        BuiltinSelectionFn::EndOfBuffer => {
            selection_function_end(es, left.as_ref(), right.as_ref(), search_mod)
        }
        x => Err(SelectionFunctionError::NotImplemented(x)),
    }?;

    if let Some(result_transform) = result_transform {
        match result_transform {
            ResultTransform::Complement => complement_transform(es, res),
            ResultTransform::Conditional => conditional_transform(res, left.as_ref()),
            ResultTransform::ConditionalComplement => {
                let res = complement_transform(es, res)?;
                conditional_transform(res, left.as_ref())
            }
            ResultTransform::ComplementConditional => {
                let res = conditional_transform(res, left.as_ref())?;
                complement_transform(es, res)
            }
        }
    } else {
        Ok(res)
    }
}