use std::env;
use std::path::Path;

use diesel::RunQueryDsl;
use diesel::r2d2::{Pool, ConnectionManager};
use diesel::pg::PgConnection;
use log::{error, info};

pub mod models;
pub mod schema;

pub fn run_migrations(pool: &Pool<ConnectionManager<PgConnection>>) {
  let mut connection = pool.get().unwrap();
  let migrations_dir = Path::new("./migrations");
  let migrations = std::fs::read_dir(&migrations_dir).unwrap();
  
  for migration in migrations {
    if migration.as_ref().unwrap().file_type().unwrap().is_dir() {
      let migration_paths = std::fs::read_dir(&migration.unwrap().path()).unwrap();

      for migration_path in migration_paths {
        if migration_path.as_ref().unwrap().file_name().eq_ignore_ascii_case("up.sql") {
          let path = &migration_path.unwrap().path();
          let contents = std::fs::read_to_string(path).expect("Unable to read from file");
          if let Err(err) = diesel::sql_query(&contents).execute(&mut connection) {
            error!("Could not run migration: {}", err);
          } else {
            info!("Successfully ran migration: {}", path.display());
          }
        }
      }
    }
  }
}

pub fn establish_connection() -> Pool<ConnectionManager<PgConnection>> {
  let database_user = env::var("POSTGRES_USER").expect("Expected a user in the environment");
  let database_password = env::var("POSTGRES_PASSWORD").expect("Expected a password in the environment");
  let database_name = env::var("POSTGRES_DB").expect("Expected a database name in the environment");

  let database_url = format!("postgres://{}:{}@localhost/{}", database_user, database_password, database_name);
  let manager = ConnectionManager::<PgConnection>::new(database_url);
  Pool::builder().build(manager).expect("Failed to create pool.")
}