//! get static and parsed environment variables
//!
//! USER_DID is parsed into a jacquard Did
//! DATABASE_URL is from DATABASE_URL or POSTGRES_USER, POSTGRES_PASSWORD, POSTGRES_HOST, and POSTGRES_DATABASE
//! USER_PDS_URL is resolved from USER_DID if ommited
//! USER_EXPORT_URL falls back to USER_PDS_URL
//! USER_SUBSCRIBE_URL falls back to USER_PDS_URL

use jacquard::prelude::IdentityResolver;
use jacquard::types::string::Did;
use std::env;

pub const DB_MAX_REQ: usize = 65535;

mod config_value;

use crate::config::config_value::ConfigValue;

// this should be loaded before the program starts any threads
// if this panics threads that access it will be poisoned
pub static USER_DID: ConfigValue<Did<'static>> = ConfigValue::new_sync(|| {
    let Ok(env) = env::var("USER_DID") else {
        panic!("USER_DID not set");
    };

    let Ok(did) = Did::new_owned(env) else {
        panic!("USER_DID was not a valid did")
    };

    did
});

pub static DATABASE_URL: ConfigValue<String> = ConfigValue::new_sync(|| {
    if let Ok(url) = env::var("DATABASE_URL") {
        return url;
    }

    let user = env::var("POSTGRES_USER");
    let db = env::var("POSTGRES_DATABASE").or_else(|_| user.clone());
    let password = env::var("POSTGRES_PASSWORD");
    let host = env::var("POSTGRES_HOST");

    if let Ok(user) = user.clone()
        && let Ok(db) = db.clone()
        && let Ok(password) = password.clone()
        && let Ok(host) = host.clone()
    {
        format!("postgres://{}:{}@{}/{}", user, password, host, db)
    } else {
        let missing = [
            (user, "USER"),
            (db, "DATABASE"),
            (password, "PASSWORD"),
            (host, "HOST"),
        ]
        .iter()
        .filter_map(|x| {
            if x.0.is_err() {
                Some(String::from("POSTGRES_") + x.1)
            } else {
                None
            }
        })
        .collect::<Vec<String>>()
        .join(", ");

        panic!(
            "Could not generate database url. Missing environment variables {}. Set DATABASE_URL to define the postgres url manually",
            missing
        );
    }
});

pub static USER_PDS_URL: ConfigValue<String> = ConfigValue::new_async(|| {
    Box::pin(async {
        if let Ok(url) = env::var("USER_PDS_URL") {
            url
        } else {
            let resolver = jacquard::identity::PublicResolver::default();
            resolver
                .pds_for_did(&self::USER_DID)
                .await
                .unwrap()
                .domain()
                .unwrap()
                .to_string()
        }
    })
});

pub static USER_EXPORT_URL: ConfigValue<String> =
    ConfigValue::new_sync(|| env::var("USER_EXPORT_URL").unwrap_or(USER_PDS_URL.clone()));

pub static USER_SUBSCRIBE_URL: ConfigValue<String> =
    ConfigValue::new_sync(|| env::var("USER_SUBSCRIBE_URL").unwrap_or(USER_PDS_URL.clone()));