use crate::connections::db_connection::db;
use crate::controllers::server_controller::ServerConstraints;
use crate::models::accounts::AccountID;
use crate::models::files::FileID;
use crate::models::movements::{Movement, MovementID, NewMovement};
use crate::models::users::UserID;
use crate::schema::movements;
use crate::services::{accounts_service, files_service};
use crate::utils::time_utils::time;
use diesel::prelude::*;
use diesel::{RunQueryDsl, sql_query};
use std::collections::HashMap;

#[derive(serde::Deserialize)]
pub struct UpdateMovementQuery {
    pub account_id: AccountID,
    pub time: u64,
    pub label: String,
    pub file_id: Option<FileID>,
    pub amount: f32,
    pub checked: bool,
}

impl UpdateMovementQuery {
    pub async fn check_error(
        &self,
        user_id: UserID,
        ref_movement: Option<MovementID>,
    ) -> anyhow::Result<Option<&'static str>> {
        let constraints = ServerConstraints::default();

        // Check movement label
        if !constraints.movement_label.check_str(&self.label) {
            return Ok(Some("Invalid movement label length!"));
        }

        // Check the account
        let Ok(account) = accounts_service::get_by_id(self.account_id).await else {
            return Ok(Some("The specified account does not exists!"));
        };
        if account.user_id() != user_id {
            return Ok(Some("The user does not own the account!"));
        }

        // Check the file
        if let Some(file_id) = self.file_id {
            let file = files_service::get_file_with_id(file_id)?;

            if file.user_id() != user_id {
                return Ok(Some("The user does not own the referenced file!"));
            }
        }

        // Check for conflict with other movements
        if let Ok(movement) =
            get_by_account_label_amount_time(self.account_id, &self.label, self.amount, self.time)
                .await
        {
            if Some(movement.id()) != ref_movement {
                return Ok(Some(
                    "A movement taken at the same time with the same label and the same amount already exists!",
                ));
            }
        }

        Ok(None)
    }
}

/// Create a new movement
pub async fn create(query: &UpdateMovementQuery) -> anyhow::Result<Movement> {
    let new_account = NewMovement {
        account_id: query.account_id.0,
        time: query.time as i64,
        label: &query.label,
        file_id: query.file_id.map(|f| f.0),
        amount: query.amount,
        checked: query.checked,
        time_create: time() as i64,
        time_update: time() as i64,
    };

    let res: Movement = diesel::insert_into(movements::table)
        .values(&new_account)
        .get_result(&mut db()?)?;

    update(res.id(), query).await?;

    Ok(res)
}

/// Update a movement
pub async fn update(id: MovementID, q: &UpdateMovementQuery) -> anyhow::Result<()> {
    diesel::update(movements::dsl::movements.filter(movements::dsl::id.eq(id.0)))
        .set((
            movements::dsl::time_update.eq(time() as i64),
            movements::dsl::account_id.eq(q.account_id.0),
            movements::dsl::time.eq(q.time as i64),
            movements::dsl::label.eq(&q.label),
            movements::dsl::file_id.eq(&q.file_id.map(|f| f.0)),
            movements::dsl::amount.eq(q.amount),
        ))
        .execute(&mut db()?)?;

    Ok(())
}

/// Get a single movement by its id
pub async fn get_by_id(movement_id: MovementID) -> anyhow::Result<Movement> {
    Ok(movements::table
        .filter(movements::dsl::id.eq(movement_id.0))
        .get_result(&mut db()?)?)
}

/// Get a single movement by account_id, label, amount and time
pub async fn get_by_account_label_amount_time(
    account_id: AccountID,
    label: &str,
    amount: f32,
    time: u64,
) -> anyhow::Result<Movement> {
    Ok(movements::table
        .filter(
            movements::dsl::account_id
                .eq(account_id.0)
                .and(movements::dsl::label.eq(label))
                .and(movements::dsl::amount.eq(amount))
                .and(movements::dsl::time.eq(time as i64)),
        )
        .get_result(&mut db()?)?)
}

/// Get the list of movements of an account
pub async fn get_list_account(account_id: AccountID) -> anyhow::Result<Vec<Movement>> {
    Ok(movements::table
        .filter(movements::dsl::account_id.eq(account_id.0))
        .get_results(&mut db()?)?)
}

table! {
    accounts_balances (account_id) {
        account_id -> Int4,
        balance -> Float4,
    }
}

#[derive(QueryableByName)]
#[diesel(table_name = accounts_balances)]
struct AccountBalance {
    account_id: i32,
    balance: f32,
}

/// Get the balances of all the accounts of the user
pub async fn get_balances(user_id: UserID) -> anyhow::Result<HashMap<AccountID, f32>> {
    let result = sql_query(format!("select a.id as account_id, sum(m.amount) as balance from accounts a right join movements m on a.id = m.account_id where a.user_id = {} group by a.id", user_id.0))
        .get_results::<AccountBalance>(&mut db()?)?;

    Ok(result
        .into_iter()
        .map(|r| (AccountID(r.account_id), r.balance))
        .collect())
}

/// Delete a movement
pub async fn delete(id: MovementID) -> anyhow::Result<()> {
    diesel::delete(movements::dsl::movements.filter(movements::dsl::id.eq(id.0)))
        .execute(&mut db()?)?;
    Ok(())
}