use reqwest::Client as HTTPClient;
use serde_json::Value;
use std::collections::HashMap;
use std::error::Error;
use std::env;

pub async fn get_auth_id(token: &str) -> Result<i32, Box<dyn Error>> {
    let auth_api_base = env::var("AUTH_URL")?;
    let gql = match auth_api_base.contains("v2") {
        true => r#"mutation { getSession { user { id } } }"#, // v2
        _ => r#"query { sessiom { user { id } } }"# // authorizer
    };
    let client = HTTPClient::new();
    let response = client
        .post(auth_api_base)
        .bearer_auth(token) // NOTE: auth token is here
        .body(gql)
        .send()
        .await?;
    let response_body: Value = response.json().await?;
    let id = response_body["data"]["getSession"]["user"]["id"]
        .as_i64()
        .ok_or("Failed to get user id by token")? as i32;
    Ok(id)
}


async fn get_shout_followers(shout_id: &str) -> Result<Vec<i32>, Box<dyn Error>> {
    let api_base = env::var("API_BASE")?;
    let gql = format!(r#"
        query {{
            shoutFollowers(shout: {}) {{
                follower {{
                    id
                }}
            }}
        }}
    "#, shout_id);
    let client = reqwest::Client::new();
    let response = client
        .post(&api_base)
        .body(gql)
        .send()
        .await?;

    let response_body: serde_json::Value = response.json().await?;

    let ids: Vec<i32> = response_body["data"]["shoutFollowers"]
        .as_array()
        .ok_or("Failed to parse follower array")?
        .iter()
        .filter_map(|f| f["follower"]["id"].as_i64().map(|id| id as i32))
        .collect();

    Ok(ids)
}


pub async fn is_fitting(listener_id: i32, payload: HashMap<String, String>) -> Result<bool, &'static str> {
    match payload.get("kind") {
        Some(kind) => {
            match kind.as_str() {
                "new_follower" => {
                    // payload is AuthorFollower
                    Ok(payload.get("author").unwrap().to_string() == listener_id.to_string())
                },
                "new_reaction" => {
                    // payload is Reaction
                    let shout_id = payload.get("shout").unwrap();
                    let recipients = get_shout_followers(shout_id).await.unwrap();

                    Ok(recipients.contains(&listener_id))
                },
                "new_shout" => {
                    // payload is Shout
                    // TODO: check all community subscribers if no then
                    // check all topics subscribers if no then
                    // check all authors subscribers
                    Ok(true)
                },
                "new_message" => {
                    // payload is Chat
                    let members_str = payload.get("members").unwrap();
                    let members = serde_json::from_str::<Vec<String>>(members_str).unwrap();
                    Ok(members.contains(&listener_id.to_string()))
                },
                _ => {
                    eprintln!("unknown payload kind");
                    eprintln!("{:?}", payload);
                    Ok(false)
                },
            }
        },
        None => {
            eprintln!("payload has no kind");
            eprintln!("{:?}", payload);
            Ok(false)
        },
    }
}