use serde_json::Value;
use std::fs::File;
use std::io::Read;
use std::io::{self, BufRead, BufReader};
use std::path::Path;

// payload limit set to 5MiB
pub const PAYLOAD_LIMIT: usize = 10_000_000;
pub const PROXY_TIMEOUT: u64 = 15;

pub const CONFIG_FILE: &str = "./config.toml";
pub const CONFIG_VERSION: u8 = 2;

pub const ADJ_LIST_FILE: &str = "./adj-list.txt";
pub const NAME_LIST_FILE: &str = "./name-list.txt";
pub const LOC_FILE: &str = "./lang.json";

pub const USER_AGENT: &str = "Actix-web";

lazy_static! {
    pub static ref CONFIG: Config = Config::init();
    pub static ref ADJ_LIST: Vec<String> =
        lines_from_file(ADJ_LIST_FILE).expect("Failed to load adjectives list");
    pub static ref NAME_LIST: Vec<String> =
        lines_from_file(NAME_LIST_FILE).expect("Failed to load names list");
    pub static ref LOC: Value = init_lang();
}

// Open LOC_FILE and store it in memory (LOC)
fn init_lang() -> Value {
    let mut file = File::open(LOC_FILE).expect("init_lang: Can't open translations file");
    let mut data = String::new();
    file.read_to_string(&mut data)
        .expect("init_lang: Can't read translations file");
    serde_json::from_str(&data).expect("init_lang(): Can't parse translations file")
}

// Open a file from its path
fn lines_from_file(filename: impl AsRef<Path>) -> io::Result<Vec<String>> {
    BufReader::new(File::open(filename)?).lines().collect()
}

#[derive(Deserialize)]
pub struct Config {
    pub listening_address: String,
    pub listening_port: u16,
    pub sncf_url: String,
    pub database_path: String,
    pub nextcloud_url: String,
    pub admin_username: String,
    pub admin_password: String,
    pub prune_days: u16,
    pub debug_mode: bool,
    pub cookie_key: String,
    pub config_version: u8,
}

// totally not copypasted from rs-short
impl Config {
    // open and parse CONFIG_FILE
    pub fn init() -> Self {
        let mut conffile = File::open(CONFIG_FILE).expect(
            r#"Config file config.toml not found.
                    Please create it using config.toml.sample."#,
        );
        let mut confstr = String::new();
        conffile
            .read_to_string(&mut confstr)
            .expect("Couldn't read config to string");
        toml::from_str(&confstr).expect("Couldn't deserialize the config. Please update at https://git.42l.fr/neil/sncf/wiki/Upgrade-from-a-previous-version --- Error")
    }

    // if config.config_version doesn't match the hardcoded version,
    // ask the admin to manually upgrade its config file
    pub fn check_version(&self) {
        if self.config_version != CONFIG_VERSION {
            eprintln!("Your configuration file is obsolete!\nPlease update it following the instructions in https://git.42l.fr/neil/sncf/wiki/Upgrade-from-a-previous-version and update its version to {}.", CONFIG_VERSION);
            panic!();
        }
    }
}

pub fn get_csrf_key() -> [u8; 32] {
    let mut key: [u8; 32] = Default::default();
    key.copy_from_slice(&CONFIG.cookie_key.clone().into_bytes()[..32]);
    key
}