iowo/crates/prowocessing/src/lib.rs

//! # This is the image processing library for iOwO
//!
//! One of the design goals for this library is, however, to be a simple, generic image processing library.
//! For now, it's just indev... lets see what comes of it!

use experimental::enum_based::{Instruction, PipelineBuilder};

/// just some experiments, to test whether the architecture i want is even possible (or how to do it). probably temporary.
/// Gonna first try string processing...
pub mod experimental {
    pub mod enum_based {
        pub enum Instruction {
            Uppercase,
            Lowercase,
        }

        pub struct Pipeline {
            pipeline: Vec<fn(String) -> String>,
        }

        impl Pipeline {
            pub fn run(&self, val: String) -> String {
                let mut current = val;

                for instr in &self.pipeline {
                    current = instr(current);
                }

                current
            }
        }

        pub struct PipelineBuilder {
            pipeline: Vec<Instruction>,
        }

        impl PipelineBuilder {
            pub fn new() -> Self {
                Self {
                    pipeline: Vec::new(),
                }
            }

            #[must_use]
            pub fn insert(mut self, instr: Instruction) -> Self {
                self.pipeline.push(instr);
                self
            }

            pub fn build(&self) -> Pipeline {
                fn uppercase(v: String) -> String {
                    str::to_uppercase(&v)
                }
                fn lowercase(v: String) -> String {
                    str::to_lowercase(&v)
                }

                let mut res = Vec::new();

                for item in &self.pipeline {
                    res.push(match item {
                        Instruction::Uppercase => uppercase,
                        Instruction::Lowercase => lowercase,
                    });
                }

                Pipeline { pipeline: res }
            }
        }

        impl Default for PipelineBuilder {
            fn default() -> Self {
                Self::new()
            }
        }
    }
}

#[test]
fn test_enums() {
    let builder = PipelineBuilder::new().insert(Instruction::Uppercase);
    let upr = builder.build();
    let upr_lowr = builder.insert(Instruction::Lowercase).build();

    assert_eq!(upr.run(String::from("Test")), String::from("TEST"));
    assert_eq!(upr_lowr.run(String::from("Test")), String::from("test"));
}