arnalisa 0.6.8

//! A bin that subtracts two values.
//!
//! ```text
//!   ┌───[subtract]───┐
//!  ⇒│a         output│⇒
//!  ⇒│b               │
//!   └────────────────┘
//! ```

use super::{
    sink_names_a_b, source_names_output, BinBuildEnvironment,
    BinDescription, Calculator, FetchItem, GetCalibration, Item,
    Iteration, Result, Scope, SinkBin, SinkNames, SourceBin, SourceId,
    SourceNames, SourceSinkBinDescription, WriteDotSimple, SINK_A, SINK_B,
    SOURCE_OUTPUT,
};
use crate::error;
use crate::item::TwoItemsExt;
use indexmap::IndexSet;
use std;

static BIN_TYPE: &str = "subtract";

/// A bin that subtracts two values.
#[derive(Debug)]
pub struct Bin {
    scope: Scope,

    source_a: Box<dyn FetchItem>,
    source_b: Box<dyn FetchItem>,

    result_output: Item,
}

impl SinkBin for Bin {}

impl SourceBin for Bin {
    fn get_source_data(&self, source: &SourceId) -> Result<Item> {
        if source.id == SOURCE_OUTPUT {
            Ok(self.result_output.clone())
        } else {
            error::MissingSourceName {
                scope: self.scope.clone(),
                name: source.id.to_string(),
                bin_type: BIN_TYPE.to_string(),
            }
            .fail()
        }
    }
}

impl Calculator for Bin {
    fn calculate(&mut self, _iteration: &Iteration) -> Result<()> {
        let a = self.source_a.fetch_item(&self.scope)?;
        let b = self.source_b.fetch_item(&self.scope)?;

        self.result_output = match (a, b).common_type() {
            (Item::B(a), Item::B(b)) => logic(a as i8, b as i8),
            (Item::I8(a), Item::I8(b)) => logic(a, b),
            (Item::I16(a), Item::I16(b)) => logic(a, b),
            (Item::I32(a), Item::I32(b)) => logic(a, b),
            (Item::I64(a), Item::I64(b)) => logic(a, b),
            (Item::U8(a), Item::U8(b)) => logic(a, b),
            (Item::U16(a), Item::U16(b)) => logic(a, b),
            (Item::U32(a), Item::U32(b)) => logic(a, b),
            (Item::U64(a), Item::U64(b)) => logic(a, b),
            (Item::F32(a), Item::F32(b)) => logic(a, b),
            (Item::F64(a), Item::F64(b)) => logic(a, b),
            _ => Item::Nothing,
        };
        Ok(())
    }
}

fn logic<T: std::ops::Sub + Into<Item>>(a: T, b: T) -> Item
where
    T: std::ops::Sub,
    Item: From<<T as std::ops::Sub>::Output>,
{
    (a - b).into()
}

/// Description for the subtract bin.
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct Description;

impl BinDescription for Description {
    type Bin = Bin;

    fn check_validity(
        &self,
        _scope: &Scope,
        _get_calibration: &mut dyn GetCalibration,
    ) -> Result<()> {
        Ok(())
    }

    fn bin_type(&self) -> &'static str {
        BIN_TYPE
    }
}

impl SinkNames for Description {
    fn sink_names(&self) -> IndexSet<String> {
        sink_names_a_b()
    }
}

impl SourceNames for Description {
    fn source_names(&self) -> Result<IndexSet<String>> {
        Ok(source_names_output())
    }
}

impl SourceSinkBinDescription for Description {
    fn build_bin(
        &self,
        scope: &Scope,
        env: &mut dyn BinBuildEnvironment,
    ) -> Result<Self::Bin> {
        Ok(Bin {
            scope: scope.clone(),
            source_a: env.resolve(SINK_A)?,
            source_b: env.resolve(SINK_B)?,
            result_output: Item::Nothing,
        })
    }
}

impl WriteDotSimple for Description {}

#[cfg(test)]
mod tests {
    use super::Description;
    use crate::bins::{directsource, verificationsink};
    use crate::Item;
    use crate::{run_bin, Result};
    use indexmap::indexset;

    #[test]
    fn simulate() -> Result<()> {
        use crate::Item::*;

        let input = directsource::Description {
            columns: indexset!["a".to_string(), "b".to_string()],
            rows: vec![
                vec![Nothing, Nothing],
                vec![Item::from(0f64), Nothing],
                vec![Nothing, Item::from(0f64)],
                vec![Item::from(0i64), Item::from(0f64)],
                vec![Item::from(1.6f64), Item::from(0f64)],
                vec![Item::from(0u64), Item::from(1.7f64)],
                vec![Item::from(1.4f64), Item::from(1.6f64)],
                vec![Item::from(1.3f64), Item::from(false)],
                vec![Item::from(true), Item::from(1f64)],
                vec![Item::from(false), Item::from(1f64)],
                vec![Item::from(5u8), Item::from(false)],
                vec![Item::from(9u16), Item::from(true)],
                vec![Item::from(false), Item::from(false)],
                vec![Item::from(false), Item::from(true)],
                vec![Item::from(true), Item::from(false)],
                vec![Item::from(true), Item::from(true)],
            ]
            .into(),
        };
        let verification = verificationsink::Description {
            columns: indexset!["output".to_string()],
            expected: vec![
                vec![Nothing],
                vec![Nothing],
                vec![Nothing],
                vec![Item::from(0f64)],
                vec![Item::from(1.6f64)],
                vec![Item::from(-1.7f64)],
                vec![Item::from(-0.2f64)],
                vec![Item::from(1.3f64)],
                vec![Item::from(0f64)],
                vec![Item::from(-1f64)],
                vec![Item::from(5u8)],
                vec![Item::from(8u16)],
                vec![Item::from(0u8)],
                vec![Item::from(-1i8)],
                vec![Item::from(1i8)],
                vec![Item::from(0i8)],
            ]
            .into(),
        };

        run_bin(&input, &Description {}, &verification)
    }
}