hello-rust-spanti 0.1.0

use std::error::Error;
use std::fs;
use std::env;

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn one_result() {
        let query = "duct";
        let contents = "\
Rust:
safe, fast, productive.
Pick three.
Duct tape.";

        assert_eq!(
            vec!["safe, fast, productive."],
            search(query, contents)
        );
    }

    #[test]
    fn case_insensitive(){
        let query = "rUsT";
        let contents = "\
Rust:
safe, fast, productive.
Pick three.
Trust me.";

        assert_eq!(
            vec!["Rust:", "Trust me."],
            search_case_insensitive(query, contents)
        );
    }
}

pub fn search_case_insensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
    let query = query.to_lowercase();
    let mut results = Vec::new();

    for line in contents.lines(){
        if line.to_lowercase().contains(&query){
            results.push(line);
        }
    }

    results
}

/// Search query str in contents, return vec of lines containing the query.
///
/// # Examples
///
/// ```
/// let query = "rUsT";
/// let contents = "\
/// Rust:
/// safe, fast, productive.
/// Pick three.
/// Trust me.";
///
/// search(query, contents);
/// 
/// ```
pub fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
    let mut results = Vec::new();

    for line in contents.lines(){
        if line.contains(query){
            results.push(line);
        }
    }

    results
}

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

impl Config{
    pub fn build(args: &[String]) -> Result<Config, &'static str>{
        if args.len() < 3 {
            return Err("not enough arguments");
        }

        let query = args[1].clone();
        let filename = args[2].clone();
        let case_sensitive = env::var("CASE_INSENSITIVE").is_err();
        
        Ok(Config { query, filename, case_sensitive})
    }
}

pub fn run(config: Config) -> Result<(), Box<dyn Error>>{
    let contents = fs::read_to_string(config.filename)?;

    let results = if config.case_sensitive {
        search(&config.query, &contents)
    } else{
        search_case_insensitive(&config.query, &contents)
    };

    for line in search(&config.query, &contents){
        println!("{}", line);
    }

    Ok(())
}