use sqlx::PgPool;

use crate::models::{
    Assignment, Availability, AvailabilityAssignmentState, Event, Function, Vehicle,
    VehicleAssignment,
};

use super::ApplicationError;

pub async fn generate_availability_assignment_list(
    pool: &PgPool,
    event: &Event,
) -> Result<Vec<(Availability, AvailabilityAssignmentState)>, ApplicationError> {
    let availabilities_in_db = Availability::read_by_date_time_area_including_user(
        pool,
        event.start.date(),
        (event.start, event.end),
        event.location.as_ref().unwrap().area_id,
    )
    .await?;

    let mut availabilities = Vec::new();
    for availability in availabilities_in_db {
        let assignments = Assignment::read_all_by_availability(pool, availability.id).await?;

        if let Some(assignment) = assignments
            .iter()
            .find(|assignment| assignment.event_id == event.id)
        {
            let state = match assignment.function {
                Function::Posten => {
                    AvailabilityAssignmentState::AssignedPosten(assignment.availability_id)
                }
                Function::Fuehrungsassistent => {
                    AvailabilityAssignmentState::AssignedFührungsassistent(
                        assignment.availability_id,
                    )
                }
                Function::Wachhabender => {
                    AvailabilityAssignmentState::AssignedWachhabender(assignment.availability_id)
                }
            };

            availabilities.push((availability, state));
            continue;
        }

        let has_start_time_during_event =
            |a: &Assignment| a.start >= event.start && a.start <= event.end;
        let has_end_time_during_event = |a: &Assignment| a.end >= event.start && a.end <= event.end;

        if assignments
            .iter()
            .any(|a| has_start_time_during_event(a) || has_end_time_during_event(a))
        {
            availabilities.push((availability, AvailabilityAssignmentState::Conflicting));
            continue;
        }

        availabilities.push((availability, AvailabilityAssignmentState::Unassigned));
    }

    //println!(" {availabilities:#?}");
    Ok(availabilities)
}

pub async fn generate_status_whether_staff_is_required(
    pool: &PgPool,
    event: &Event,
) -> Result<(bool, bool, bool), ApplicationError> {
    let existing_assignments_for_event = Assignment::read_all_by_event(pool, event.id).await?;

    let further_posten_required = existing_assignments_for_event
        .iter()
        .filter(|a| a.function == Function::Posten)
        .count()
        < event.amount_of_posten as usize;

    let further_fuehrungsassistent_required = event.voluntary_fuehrungsassistent
        && existing_assignments_for_event
            .iter()
            .all(|a| a.function != Function::Fuehrungsassistent);

    let further_wachhabender_required = event.voluntary_wachhabender
        && existing_assignments_for_event
            .iter()
            .all(|a| a.function != Function::Wachhabender);

    //println!("further_posten {further_posten_required}");
    Ok((
        further_posten_required,
        further_fuehrungsassistent_required,
        further_wachhabender_required,
    ))
}

pub async fn generate_vehicles_assigned_and_available(
    pool: &PgPool,
    event: &Event,
) -> Result<(Vec<Vehicle>, Vec<Vehicle>), ApplicationError> {
    let all_vehicles = Vehicle::read_all(pool).await?;
    let existing_vehicle_assignments_for_event =
        VehicleAssignment::read_all_by_event(pool, event.id).await?;
    let (vehicles_assigned, vehicles_available): (Vec<Vehicle>, Vec<Vehicle>) =
        all_vehicles.into_iter().partition(|v| {
            existing_vehicle_assignments_for_event
                .iter()
                .any(|va| va.vehicle_id == v.id)
        });

    Ok((vehicles_assigned, vehicles_available))
}