minigrep_by_wjw 0.1.0

use std::fs;
use std::error::Error;
use std::env;
pub struct Config {
    pub query: String,
    pub filename: String,
    pub case_sensitive: bool,
}

impl Config {
    pub fn new( 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 results {
        println!("{}", line);
    }
    Ok(())
}

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

    #[test]
    #[ignore]
    fn one_result() {
        let query = "dUct";
        let contents = "hello\nsafe, fast, productive.\nnonono";

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

    #[test]
    fn case_sensitive() {
        let query = "dUct";
        let contents = "hello\nsafe, fast, productive.\ndUcthahaha";

        assert_eq! (
            vec!["dUcthahaha"],
            search(query, contents)
        );
    }

    #[test]
    fn case_insensitive() {
        let query = "dUct";
        let contents = "hello\nsafe, fast, productive.\nDUcto";

        assert_eq! (
            vec!["safe, fast, productive.","DUcto"],
            search_case_insensitive(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 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
}