miniprep_ot 0.2.0

//! # Mini grep
//!
//! `miniprep_ot` is a command-line interface to grep.
//!
//! It is created as a part of my Rust learning curve.

use std::error::Error;
use std::{env, fs};

pub fn run(config: &Config) -> Result<(), Box<dyn Error>> {
    let content = fs::read_to_string(&config.filename)?;
    let results = if config.ignore_case {
        search_case_insensitive(&config.query, &content)
    } else {
        search(&config.query, &content)
    };

    for line in results {
        println!("{line}");
    }
    Ok(())
}

pub struct Config {
    pub filename: String,
    pub ignore_case: bool,
    pub query: String,
}

impl Config {
    pub fn build(mut args: impl Iterator<Item = String>) -> Result<Config, &'static str> {
        // skip execution file name: args[0]
        args.next();

        let query = match args.next() {
            Some(arg) => arg,
            None => return Err("Didn't get a query string"),
        };

        let filename = match args.next() {
            Some(arg) => arg,
            None => return Err("Didn't get a file path"),
        };
        let ignore_case = env::var("IGNORE_CASE").is_ok();
        Ok(Config {
            filename,
            ignore_case,
            query,
        })
    }
}

/// Do case-sensitive search in content of `query`
///
/// # Examples
///     let query = "duct";
///     let content = "Rust:\nsafe, fast, productive.\n Pick three.\n Duct type.";
///     assert_eq!(vec!["safe, fast, productive."], miniprep_ot::search(query, content));
/// }
///
///
pub fn search<'a>(query: &str, content: &'a str) -> Vec<&'a str> {
    // let mut results = Vec::new();
    content
        .lines()
        .filter(|line| line.contains(query))
        .collect()
}

/// Do case-insensitive search in content of `query`
///
/// # Examples
///     let query = "rUsT";
///     let content = "Rust:\nsafe, fast, productive.\nPick three.\nTrust me";
///     assert_eq!(
///         vec!["Rust:", "Trust me"],
///         miniprep_ot::search_case_insensitive(query, content)
///     );
/// }
///
///
pub fn search_case_insensitive<'a>(query: &str, content: &'a str) -> Vec<&'a str> {
    let query = query.to_lowercase();
    content
        .lines()
        .filter(|line| line.to_lowercase().contains(&query))
        .collect()
}

/// Adds one to the number given.
///
/// # Examples
///
/// ```
/// let arg = 6;
/// let answer = miniprep_ot::add_one(arg);
///
/// assert_eq!(7, answer);
/// ```
pub fn add_one(x: i32) -> i32 {
    x + 1
}

#[cfg(test)]
mod tests {}