use cynic::{GraphQlResponse, QueryBuilder};
use serde::{Deserialize, Serialize};
use std::path::Path;

pub mod search_games;
pub use search_games::*;
pub mod tournament_sets;
pub use tournament_sets::*;

use schema::schema;

// Types

// HACK: Unfortunately, start.gg seems to use integers for its ID type, whereas
// cynic always assumes that IDs are strings. To get around that, we define a
// new scalar type that serializes to u64.
#[derive(cynic::Scalar, Debug, Copy, Clone)]
pub struct ID(pub u64);

// Wrapper types to differentiate between different types of IDs
#[derive(Debug, Copy, Clone)]
pub struct VideogameId(pub u64);
#[derive(Debug, Copy, Clone)]
pub struct EntrantId(pub u64);

#[derive(cynic::Scalar, Debug, Clone)]
pub struct Timestamp(pub u64);

// Auth key

pub fn get_auth_key(config_dir: &Path) -> Option<String> {
    use std::env::{var, VarError};
    use std::fs::read_to_string;

    match var("AUTH_KEY") {
        Ok(key) => Some(key),
        Err(VarError::NotUnicode(_)) => panic!("Invalid authorization key"),
        Err(VarError::NotPresent) => {
            let mut auth_file = config_dir.to_owned();
            auth_file.push("auth.txt");
            read_to_string(auth_file).ok().and_then(|s| {
                let trimmed = s.trim();
                if trimmed.is_empty() {
                    None
                } else {
                    Some(trimmed.to_owned())
                }
            })
        }
    }
}

// Query machinery

pub trait QueryUnwrap<Vars>: 'static + QueryBuilder<Vars> {
    type VarsUnwrapped;
    type Unwrapped;

    fn wrap_vars(vars: Self::VarsUnwrapped) -> Vars;
    fn unwrap_response(response: GraphQlResponse<Self>) -> Option<Self::Unwrapped>;
}

// Generic function for running start.gg queries
pub fn run_query<Builder, Vars>(
    vars: Builder::VarsUnwrapped,
    auth: &str,
) -> Option<Builder::Unwrapped>
where
    Builder: QueryUnwrap<Vars>,
    Vars: Serialize,
    for<'de> Builder: Deserialize<'de>,
{
    use cynic::http::ReqwestBlockingExt;

    let query = Builder::build(Builder::wrap_vars(vars));

    let response = reqwest::blocking::Client::new()
        .post("https://api.start.gg/gql/alpha")
        .header("Authorization", String::from("Bearer ") + auth)
        .run_graphql(query);

    Builder::unwrap_response(response.unwrap())
}