extern crate regex;
extern crate md5;
extern crate image_base64_wasm;

mod tests {
    use std::fs::File;
    use std::io::Read;
    use std::string::String;
    use std::path::Path;
    use std::io::Write;
    use std::fs;
    use std::str;
    use md5::Digest;
    use image_base64_wasm::{to_base64, from_base64};


    static FILE_NAME: &'static str = "nyan";

    #[test]
    fn jpg_to_base64() {
        image_to_base64("jpg");
    }

    #[test]
    fn gif_to_base64() {
        image_to_base64("gif");
    }

    #[test]
    fn png_to_base64() {
        image_to_base64("png");
    }

    #[test]
    fn ico_to_base64() {
        image_to_base64("ico");
    }

    fn image_to_base64(file_type: &str) {
        let mut file = match File::open(format!("res/{}_data", file_type)) {
            Err(why) => panic!("couldn't open {}", why),
            Ok(file) => file,
        };
        let mut buffer = String::new();
        match file.read_to_string(&mut buffer) {
            Err(why) => panic!("couldn't read {}", why),
            Ok(_) => {},
        }
        let base64 = to_base64(&format!("res/{}.{}", FILE_NAME, file_type));
        assert_eq!(base64, buffer);
    }

    #[test]
    fn base64_to_jpg() {
        base64_to_image("jpg");
        validate("jpg");
    }

    #[test]
    fn base64_to_gif() {
        base64_to_image("gif");
        validate("gif");
    }

    #[test]
    fn base64_to_png() {
        base64_to_image("png");
        validate("png");
    }

    #[test]
    fn base64_to_ico() {
        base64_to_image("ico");
        validate("ico");
    }

    fn base64_to_image(file_type: &str) {
        let mut original = match File::open(format!("res/{}_data", file_type)) {
            Err(why) => panic!("couldn't open {}", why),
            Ok(file) => file,
        };
        let mut base64 = String::new();
        match original.read_to_string(&mut base64) {
            Err(why) => panic!("couldn't read {}", why),
            Ok(_) => {},
        }
        let img = from_base64(base64);
        let mut output = File::create(&Path::new(&format!("output/{}.{}", FILE_NAME, file_type))).unwrap();
        output.write_all(img.as_slice()).unwrap();
    }

    fn validate(file_type: &str) {
        assert_eq!(get_file_size("res", file_type), get_file_size("output", file_type));
        assert_eq!(get_hash("res", file_type), get_hash("output", file_type));
    }

    fn get_hash(dir: &str, file_type: &str) -> Digest {
        let mut file = match File::open(&format!("{}/{}.{}", dir, FILE_NAME, file_type)) {
            Err(why) => panic!("couldn't open {}", why),
            Ok(file) => file,
        };
        let mut file_vec = Vec::new();
        match file.read_to_end(&mut file_vec) {
            Err(why) => panic!("couldn't read {}", why),
            Ok(_) => {},
        }
        let file_arr = vector_as_u8_4_array(file_vec);
        return md5::compute(file_arr);
    }

    fn get_file_size(dir: &str, file_type: &str) -> u64 {
        let meta = match fs::metadata(&format!("{}/{}.{}", dir, FILE_NAME, file_type)) {
            Err(why) => panic!("couldn't read {}", why),
            Ok(meta) => meta,
        };
        meta.len()
    }

    fn vector_as_u8_4_array(vector: Vec<u8>) -> [u8; 4] {
        let mut arr = [0u8; 4];
        for (place, element) in arr.iter_mut().zip(vector.iter()) {
            *place = *element;
        }
        arr
    }
}