extern crate rand;
use rand::prelude::*;

// GOALS: 
// 
// make it as generic as possible so that people can
// load in their own custom alphabets through an API
// or use the default parameters
//
// then publish to crates.io

// Function to determine passphrase difficulty: 
// easy, medium, hard, random, errror
fn difficulty(mode: &str) -> i32 {
    if mode == "easy" {
        thread_rng().gen_range(1, 3)
    } else if mode == "medium" {
        thread_rng().gen_range(3, 6)
    } else if mode == "hard" {
        thread_rng().gen_range(6, 9)
    } else if mode == "random" {
        thread_rng().gen_range(1, 9)
    } else {
        println!("Not a valid mode. Please set mode to easy, medium, or hard");
        0
    }
}

// Function to join all padding types into one vector
fn join_padding_types<'a>(numbers: Vec<&'a str>,
                          letters: Vec<&'a str>,
                          symbols: Vec<&'a str>,
                          other: Vec<&'a str>) -> Vec<&'a str> {
    
    let mut v: Vec<&str> = Vec::new();
    
    v.append(&mut numbers.clone());
    v.append(&mut letters.clone());
    v.append(&mut symbols.clone());
    v.append(&mut other.clone());
    
    v
    
}

// Function to create a padding string from the padding vector
fn create_padding(stuff: Vec<&str>,
                  len: i32) -> Vec<&str> {
    
    let mut v: Vec<&str> = Vec::new();
    let l = thread_rng().gen_range(1, len);
    let s = thread_rng().gen_range(1, stuff.len());
    
    for _i in 0..l {
        v.push(stuff[s]);
    }
        
    v
    
}

// Function to generate a passphrase with padding
fn passphrase(words: Vec<&str>,
              padding_chars: Vec<&str>,
              mode: &str) -> String {
    
    // init variables
    let mut v: Vec<&str> = Vec::new();
    let mut rng = thread_rng();
    let d = difficulty(mode);
    let p = create_padding(padding_chars, d);
    
    // add words and padding to vector
    for i in 0..d {
        let w = rng.gen_range(1, words.len());
        v.push(words[w]);
        v.append(&mut p.clone());
    }

    // convert vector to string
    let mut passphrase = String::new();
    for i in v {
        passphrase.push_str(i);
    }

    // return passphrase string
    passphrase
    
}

// Function to create a random password to compare with 
// a random passphrase
fn password(stuff: Vec<&str>,
            len: i32) -> String {
        
    // init variables
    let mut v: Vec<&str> = Vec::new();
    let mut rng = thread_rng();
    
    // add random values to a vector
    for i in 0..len {
        let s = thread_rng().gen_range(1, stuff.len());
        v.push(stuff[s])
    }
        
    // convert vector to string
    let mut password = String::new();
    for i in v {
        password.push_str(i);
    }
    
    // return password string
    password
}



fn main() {

    // Create alphabets
    let words = vec!["apple", "bagel", "cat", "dolphin", "elephant", "frog", "gopher", "horse", "iguana", "jackrabbit", "kangaroo", "lizzard", "monkey", "nightengale", "otter", "prayingmantis", "quail", "rooster", "snake", "turtle", "ummm", "velocorapter", "walrus", "x", "yarr", "zebra"];
    let nums = vec!["0","1","2","3","4","5","6","7","8","9"];
    let symbols = vec!["`", "~", "!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "-", "_", "=", "+", "[", "{", "]", "}", "?", ".", ">", ",", "<", ";", "|", ":", "/"]; 
    let letters = vec!["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"];
    let other = vec![""];
    let mode = "medium"; // easy, medium, hard, random
    let padding = join_padding_types(nums, symbols, letters, other);

    // Create passphrase and password
    let _passphrase = passphrase(words.clone(), padding.clone(), mode);
    let _password = password(padding.clone(), _passphrase.len() as i32);

    // Print results for comparison
    println!("Which is easier to remember?\n");
    println!("password: {}", _password);
    println!("password length: {}", _password.len());
    println!("\nor...\n");
    println!("passphrase: {}", _passphrase);
    println!("passphrase length: {}", _passphrase.len());
    
    
}