use crate::PerformCrud;
use actix_web::web::Data;
use lemmy_api_common::{blocking, password_length_check, person::*};
use lemmy_apub::{
  generate_apub_endpoint,
  generate_followers_url,
  generate_inbox_url,
  generate_shared_inbox_url,
  EndpointType,
};
use lemmy_db_queries::{
  source::{local_user::LocalUser_, site::Site_},
  Crud,
  Followable,
  Joinable,
  ListingType,
  SortType,
};
use lemmy_db_schema::{
  source::{
    community::*,
    local_user::{LocalUser, LocalUserForm},
    person::*,
    site::*,
  },
  CommunityId,
};
use lemmy_db_views_actor::person_view::PersonViewSafe;
use lemmy_utils::{
  apub::generate_actor_keypair,
  claims::Claims,
  settings::structs::Settings,
  utils::{check_slurs, is_valid_actor_name},
  ApiError,
  ConnectionId,
  LemmyError,
};
use lemmy_websocket::{messages::CheckCaptcha, LemmyContext};

#[async_trait::async_trait(?Send)]
impl PerformCrud for Register {
  type Response = LoginResponse;

  async fn perform(
    &self,
    context: &Data<LemmyContext>,
    _websocket_id: Option<ConnectionId>,
  ) -> Result<LoginResponse, LemmyError> {
    let data: &Register = self;

    // Make sure site has open registration
    if let Ok(site) = blocking(context.pool(), move |conn| Site::read_simple(conn)).await? {
      if !site.open_registration {
        return Err(ApiError::err("registration_closed").into());
      }
    }

    password_length_check(&data.password)?;

    // Make sure passwords match
    if data.password != data.password_verify {
      return Err(ApiError::err("passwords_dont_match").into());
    }

    // Check if there are admins. False if admins exist
    let no_admins = blocking(context.pool(), move |conn| {
      PersonViewSafe::admins(conn).map(|a| a.is_empty())
    })
    .await??;

    // If its not the admin, check the captcha
    if !no_admins && Settings::get().captcha.enabled {
      let check = context
        .chat_server()
        .send(CheckCaptcha {
          uuid: data
            .captcha_uuid
            .to_owned()
            .unwrap_or_else(|| "".to_string()),
          answer: data
            .captcha_answer
            .to_owned()
            .unwrap_or_else(|| "".to_string()),
        })
        .await?;
      if !check {
        return Err(ApiError::err("captcha_incorrect").into());
      }
    }

    check_slurs(&data.username)?;

    let actor_keypair = generate_actor_keypair()?;
    if !is_valid_actor_name(&data.username) {
      return Err(ApiError::err("invalid_username").into());
    }
    let actor_id = generate_apub_endpoint(EndpointType::Person, &data.username)?;

    // We have to create both a person, and local_user

    // Register the new person
    let person_form = PersonForm {
      name: data.username.to_owned(),
      actor_id: Some(actor_id.clone()),
      private_key: Some(Some(actor_keypair.private_key)),
      public_key: Some(Some(actor_keypair.public_key)),
      inbox_url: Some(generate_inbox_url(&actor_id)?),
      shared_inbox_url: Some(Some(generate_shared_inbox_url(&actor_id)?)),
      admin: Some(no_admins),
      ..PersonForm::default()
    };

    // insert the person
    let inserted_person = blocking(context.pool(), move |conn| {
      Person::create(conn, &person_form)
    })
    .await?
    .map_err(|_| ApiError::err("user_already_exists"))?;

    // Create the local user
    // TODO some of these could probably use the DB defaults
    let local_user_form = LocalUserForm {
      person_id: inserted_person.id,
      email: Some(data.email.to_owned()),
      password_encrypted: data.password.to_owned(),
      show_nsfw: Some(data.show_nsfw),
      show_bot_accounts: Some(true),
      theme: Some("browser".into()),
      default_sort_type: Some(SortType::Active as i16),
      default_listing_type: Some(ListingType::Subscribed as i16),
      lang: Some("browser".into()),
      show_avatars: Some(true),
      show_scores: Some(true),
      show_read_posts: Some(true),
      show_new_post_notifs: Some(false),
      send_notifications_to_email: Some(false),
    };

    let inserted_local_user = match blocking(context.pool(), move |conn| {
      LocalUser::register(conn, &local_user_form)
    })
    .await?
    {
      Ok(lu) => lu,
      Err(e) => {
        let err_type = if e.to_string()
          == "duplicate key value violates unique constraint \"local_user_email_key\""
        {
          "email_already_exists"
        } else {
          "user_already_exists"
        };

        // If the local user creation errored, then delete that person
        blocking(context.pool(), move |conn| {
          Person::delete(conn, inserted_person.id)
        })
        .await??;

        return Err(ApiError::err(err_type).into());
      }
    };

    let main_community_keypair = generate_actor_keypair()?;

    // Create the main community if it doesn't exist
    let main_community = match blocking(context.pool(), move |conn| {
      Community::read(conn, CommunityId(2))
    })
    .await?
    {
      Ok(c) => c,
      Err(_e) => {
        let default_community_name = "main";
        let actor_id = generate_apub_endpoint(EndpointType::Community, default_community_name)?;
        let community_form = CommunityForm {
          name: default_community_name.to_string(),
          title: "The Default Community".to_string(),
          description: Some("The Default Community".to_string()),
          actor_id: Some(actor_id.to_owned()),
          private_key: Some(main_community_keypair.private_key),
          public_key: Some(main_community_keypair.public_key),
          followers_url: Some(generate_followers_url(&actor_id)?),
          inbox_url: Some(generate_inbox_url(&actor_id)?),
          shared_inbox_url: Some(Some(generate_shared_inbox_url(&actor_id)?)),
          ..CommunityForm::default()
        };
        blocking(context.pool(), move |conn| {
          Community::create(conn, &community_form)
        })
        .await??
      }
    };

    // Sign them up for main community no matter what
    let community_follower_form = CommunityFollowerForm {
      community_id: main_community.id,
      person_id: inserted_person.id,
      pending: false,
    };

    let follow = move |conn: &'_ _| CommunityFollower::follow(conn, &community_follower_form);
    if blocking(context.pool(), follow).await?.is_err() {
      return Err(ApiError::err("community_follower_already_exists").into());
    };

    // If its an admin, add them as a mod and follower to main
    if no_admins {
      let community_moderator_form = CommunityModeratorForm {
        community_id: main_community.id,
        person_id: inserted_person.id,
      };

      let join = move |conn: &'_ _| CommunityModerator::join(conn, &community_moderator_form);
      if blocking(context.pool(), join).await?.is_err() {
        return Err(ApiError::err("community_moderator_already_exists").into());
      }
    }

    // Return the jwt
    Ok(LoginResponse {
      jwt: Claims::jwt(inserted_local_user.id.0)?,
    })
  }
}
