//! Avatar API handlers for user UI.
//!
//! Handles avatar data retrieval and slot updates.
//! Note: Emotion switching is handled via WebSocket.

use axum::Json;
use axum::extract::Path;

use chattyness_db::{
    models::{AssignSlotRequest, AvatarWithPaths, ClearSlotRequest},
    queries::{avatars, realms},
};
use chattyness_error::AppError;

use crate::auth::{AuthUser, RlsConn};

/// Get full avatar with all paths resolved.
///
/// GET /api/realms/{slug}/avatar
///
/// Returns the complete avatar data with all inventory UUIDs resolved to asset paths.
/// This enables client-side emotion availability computation and rendering without
/// additional server queries.
pub async fn get_avatar(
    rls_conn: RlsConn,
    AuthUser(user): AuthUser,
    Path(slug): Path<String>,
) -> Result<Json<AvatarWithPaths>, AppError> {
    let mut conn = rls_conn.acquire().await;

    // Get realm
    let realm = realms::get_realm_by_slug(&mut *conn, &slug)
        .await?
        .ok_or_else(|| AppError::NotFound(format!("Realm '{}' not found", slug)))?;

    // Get full avatar with paths
    let avatar = avatars::get_avatar_with_paths_conn(&mut *conn, user.id, realm.id)
        .await?
        .unwrap_or_default();

    Ok(Json(avatar))
}

/// Assign an inventory item to an avatar slot.
///
/// PUT /api/realms/{slug}/avatar/slot
///
/// Assigns the specified inventory item to the given layer and position
/// in the user's active avatar.
pub async fn assign_slot(
    rls_conn: RlsConn,
    AuthUser(user): AuthUser,
    Path(slug): Path<String>,
    Json(req): Json<AssignSlotRequest>,
) -> Result<Json<AvatarWithPaths>, AppError> {
    // Guests cannot customize their avatar
    if user.is_guest() {
        return Err(AppError::Forbidden(
            "Avatar customization is disabled for guests, please register first.".to_string(),
        ));
    }

    req.validate()?;

    let mut conn = rls_conn.acquire().await;

    // Get realm
    let realm = realms::get_realm_by_slug(&mut *conn, &slug)
        .await?
        .ok_or_else(|| AppError::NotFound(format!("Realm '{}' not found", slug)))?;

    // Update the slot
    let column_name = req.column_name();
    avatars::update_avatar_slot(
        &mut *conn,
        user.id,
        realm.id,
        &column_name,
        Some(req.inventory_item_id),
    )
    .await?;

    // Return updated avatar
    let avatar = avatars::get_avatar_with_paths_conn(&mut *conn, user.id, realm.id)
        .await?
        .unwrap_or_default();

    Ok(Json(avatar))
}

/// Clear an avatar slot.
///
/// DELETE /api/realms/{slug}/avatar/slot
///
/// Removes any inventory item from the given layer and position
/// in the user's active avatar.
pub async fn clear_slot(
    rls_conn: RlsConn,
    AuthUser(user): AuthUser,
    Path(slug): Path<String>,
    Json(req): Json<ClearSlotRequest>,
) -> Result<Json<AvatarWithPaths>, AppError> {
    // Guests cannot customize their avatar
    if user.is_guest() {
        return Err(AppError::Forbidden(
            "Avatar customization is disabled for guests, please register first.".to_string(),
        ));
    }

    req.validate()?;

    let mut conn = rls_conn.acquire().await;

    // Get realm
    let realm = realms::get_realm_by_slug(&mut *conn, &slug)
        .await?
        .ok_or_else(|| AppError::NotFound(format!("Realm '{}' not found", slug)))?;

    // Clear the slot
    let column_name = req.column_name();
    avatars::update_avatar_slot(&mut *conn, user.id, realm.id, &column_name, None).await?;

    // Return updated avatar
    let avatar = avatars::get_avatar_with_paths_conn(&mut *conn, user.id, realm.id)
        .await?
        .unwrap_or_default();

    Ok(Json(avatar))
}