use sea_orm::*;
use serde::Serialize;

use ::entity::{candidate, candidate::Entity as Candidate, parent};

use crate::Query;

pub const PAGE_SIZE: u64 = 20;

#[derive(FromQueryResult, Serialize)]
pub struct CandidateParentResult {
    pub application: i32,
    pub name: Option<String>,
    pub surname: Option<String>,
    pub study: Option<String>,    
    pub citizenship: Option<String>,

    pub parent_name: Option<String>,
    pub parent_surname: Option<String>,
}

#[derive(FromQueryResult, Serialize)]
pub struct CandidateWithParent { // TODO: use this instead of (Candidate, Parent)???
    pub application: i32,
    pub name: Option<String>,
    pub surname: Option<String>,
    pub birth_surname: Option<String>,
    pub birthplace: Option<String>,
    pub birthdate: Option<String>,
    pub address: Option<String>,
    pub telephone: Option<String>,
    pub citizenship: Option<String>,
    pub email: Option<String>,
    pub sex: Option<String>,
    pub study: Option<String>,
    pub personal_identification_number: Option<String>,

    pub parent_name: Option<String>,
    pub parent_surname: Option<String>,
    pub parent_telephone: Option<String>,
    pub parent_email: Option<String>,
}

impl Query {
    pub async fn find_candidate_by_id(
        db: &DbConn,
        id: i32,
    ) -> Result<Option<candidate::Model>, DbErr> {
        Candidate::find_by_id(id)
            .one(db)
            .await
    }

    pub async fn list_candidates(
        db: &DbConn,
        field_of_study_opt: Option<String>,
        page: Option<u64>,
    ) -> Result<Vec<CandidateParentResult>, DbErr> {
        let select = Candidate::find();
        let query = if let Some(study) = field_of_study_opt {
           select.filter(candidate::Column::Study.eq(study)) 
        } else {
            select
        }
            .order_by(candidate::Column::Application, Order::Asc)
            .join(JoinType::InnerJoin, candidate::Relation::Parent.def())
            .column_as(parent::Column::Name, "parent_name")
            .column_as(parent::Column::Surname, "parent_surname")
            .into_model::<CandidateParentResult>()
            .paginate(db, PAGE_SIZE);

        if let Some(page) = page {
            query.fetch_page(page).await
        } else {
            query.fetch().await
        }
    }


    pub async fn list_all_candidates_with_parents(
        db: &DbConn,
    ) -> Result<Vec<CandidateWithParent>, DbErr> {
        Candidate::find()
            .order_by(candidate::Column::Application, Order::Asc)
            .join(JoinType::InnerJoin, candidate::Relation::Parent.def())
            .column_as(parent::Column::Name, "parent_name")
            .column_as(parent::Column::Surname, "parent_surname")
            .column_as(parent::Column::Telephone, "parent_telephone")
            .column_as(parent::Column::Email, "parent_email")
            .into_model::<CandidateWithParent>()
            .all(db)
            .await
    }
    
}

#[cfg(test)]
mod tests {
    use sea_orm::{ActiveModelTrait, Set};

    use entity::candidate;

    use crate::Query;
    use crate::util::get_memory_sqlite_connection;

    #[tokio::test]
    async fn test_find_candidate_by_id() {
        let db = get_memory_sqlite_connection().await;
        let candidate = candidate::ActiveModel {
            application: Set(103158),
            code: Set("test".to_string()),
            public_key: Set("test".to_string()),
            private_key: Set("test".to_string()),
            personal_identification_number_hash: Set("test".to_string()),
            created_at: Set(chrono::offset::Local::now().naive_local()),
            updated_at: Set(chrono::offset::Local::now().naive_local()),
            ..Default::default()
        }
        .insert(&db)
        .await
        .unwrap();

        let candidate =  Query::find_candidate_by_id(&db, candidate.application)
            .await
            .unwrap();
        assert!(candidate.is_some());
    }
}