rustango 0.22.1

//! Axum REST router for the [`MediaManager`] surface.
//!
//! Mounted under any prefix you like; the conventional choice is
//! `/media`. All responses are JSON (no auto-CSRF — you wire that
//! at the outer router level via [`crate::forms::csrf`]).
//!
//! ## Endpoints
//!
//! | Method | Path                              | Purpose |
//! |--------|-----------------------------------|---------|
//! | POST   | `/uploads/begin`                  | Start a direct browser upload — returns `{media_id, upload_url, expires_at}`. |
//! | POST   | `/uploads/{id}/finalize`          | Confirm the storage object landed; flips the row Pending→Ready. |
//! | GET    | `/media/{id}`                     | Single Media row + URL + presigned link. |
//! | DELETE | `/media/{id}`                     | Soft-delete the Media row (storage preserved). |
//! | POST   | `/media/{id}/move`                | Move Media to another collection: body `{collection_id?: i64}`. |
//! | POST   | `/media/{id}/tags`                | Replace tag set: body `{slugs: ["a","b"]}`. |
//! | DELETE | `/media/{id}/tags/{slug}`         | Remove a single tag. |
//! | POST   | `/collections`                    | Create: body `{name, slug, parent_id?, description?}`. |
//! | GET    | `/collections`                    | List every non-deleted collection. |
//! | GET    | `/collections/{id}`               | Single collection. |
//! | GET    | `/collections/{id}/contents`      | Media in the collection. `?recursive=1` to include sub-folders. |
//! | DELETE | `/collections/{id}`               | Soft-delete a collection (Media inside orphaned, NOT deleted). |
//! | POST   | `/tags`                           | Create / upsert: body `{slug}`. |
//! | GET    | `/tags`                           | All tags. |
//! | GET    | `/tags/popular`                   | Top tags by usage count. `?limit=N`. |
//! | GET    | `/tags/{slug}/media`              | Media carrying the tag. `?limit=N&offset=N`. |
//!
//! ## Quick start
//!
//! ```ignore
//! use rustango::media::{Media, MediaManager, router::media_router};
//! use rustango::storage::StorageRegistry;
//!
//! Media::ensure_table(&pool).await?;
//! rustango::media::ensure_all_tables(&pool).await?;
//!
//! let manager = MediaManager::new(pool.clone(), registry);
//! let app = axum::Router::new()
//!     .nest("/media", media_router(manager));
//! ```

use std::sync::Arc;
use std::time::Duration;

use axum::extract::{Path, Query, State};
use axum::http::StatusCode;
use axum::response::{IntoResponse, Response};
use axum::routing::{delete, get, post};
use axum::{Json, Router};
use serde::{Deserialize, Serialize};
use serde_json::Value;

use super::{
    Media, MediaCollection, MediaError, MediaManager, MediaStatus, MediaTag, UploadIntent,
};

#[allow(dead_code)]
const DEFAULT_PRESIGN_TTL_SECS: u64 = 3600;

/// Build the media router. Pass to `axum::Router::nest("/media", ...)`.
pub fn media_router(manager: MediaManager) -> Router {
    let state = Arc::new(manager);
    Router::new()
        .route("/uploads/begin", post(begin_upload_handler))
        .route("/uploads/{id}/finalize", post(finalize_upload_handler))
        .route("/media/{id}", get(get_media_handler).delete(delete_media_handler))
        .route("/media/{id}/move", post(move_media_handler))
        .route("/media/{id}/tags", post(set_tags_handler))
        .route("/media/{id}/tags/{slug}", delete(untag_handler))
        .route("/collections", post(create_collection_handler).get(list_collections_handler))
        .route("/collections/{id}", get(get_collection_handler).delete(delete_collection_handler))
        .route("/collections/{id}/contents", get(collection_contents_handler))
        .route("/tags", post(create_tag_handler).get(list_tags_handler))
        .route("/tags/popular", get(popular_tags_handler))
        .route("/tags/{slug}/media", get(media_with_tag_handler))
        .with_state(state)
}

// =====================================================================
// Wire types
// =====================================================================

#[derive(Debug, Deserialize)]
struct BeginUploadBody {
    disk: String,
    #[serde(default)]
    key_prefix: String,
    mime: String,
    original_filename: String,
    size_bytes: i64,
    #[serde(default)]
    uploaded_by_id: Option<i64>,
    #[serde(default)]
    collection_id: Option<i64>,
    #[serde(default = "default_ttl_secs")]
    ttl_secs: u64,
}

fn default_ttl_secs() -> u64 {
    300
}

#[derive(Debug, Serialize)]
struct UploadTicketBody {
    media_id: i64,
    upload_url: String,
    expires_at: chrono::DateTime<chrono::Utc>,
    disk: String,
    storage_key: String,
}

#[derive(Debug, Serialize)]
struct MediaResponse {
    id: i64,
    disk: String,
    storage_key: String,
    mime: String,
    size_bytes: i64,
    original_filename: String,
    status: String,
    uploaded_at: chrono::DateTime<chrono::Utc>,
    uploaded_by_id: Option<i64>,
    derived_from_id: Option<i64>,
    collection_id: Option<i64>,
    metadata: Value,
    /// CDN-aware public URL when available.
    url: Option<String>,
    /// Time-limited GET URL (1h by default), if the backend signs.
    presigned_url: Option<String>,
    tags: Vec<String>,
}

impl MediaResponse {
    async fn from_row(manager: &MediaManager, m: Media) -> Result<Self, MediaError> {
        let id = match m.id {
            crate::sql::Auto::Set(v) => v,
            _ => 0,
        };
        let url = manager.url(&m);
        let presigned = manager.presigned_get(&m, Duration::from_secs(DEFAULT_PRESIGN_TTL_SECS)).await;
        let tags = manager
            .tags_for(id)
            .await?
            .into_iter()
            .map(|t| t.slug)
            .collect();
        Ok(Self {
            id,
            disk: m.disk,
            storage_key: m.storage_key,
            mime: m.mime,
            size_bytes: m.size_bytes,
            original_filename: m.original_filename,
            status: m.status,
            uploaded_at: m.uploaded_at,
            uploaded_by_id: m.uploaded_by_id,
            derived_from_id: m.derived_from_id,
            collection_id: m.collection_id,
            metadata: m.metadata,
            url,
            presigned_url: presigned,
            tags,
        })
    }
}

#[derive(Debug, Deserialize)]
struct MoveBody {
    collection_id: Option<i64>,
}

#[derive(Debug, Deserialize)]
struct SetTagsBody {
    slugs: Vec<String>,
}

#[derive(Debug, Deserialize)]
struct CreateCollectionBody {
    name: String,
    slug: String,
    #[serde(default)]
    parent_id: Option<i64>,
    #[serde(default)]
    description: String,
}

#[derive(Debug, Serialize)]
struct CollectionResponse {
    id: i64,
    name: String,
    slug: String,
    parent_id: Option<i64>,
    description: String,
    created_at: chrono::DateTime<chrono::Utc>,
}

impl From<MediaCollection> for CollectionResponse {
    fn from(c: MediaCollection) -> Self {
        let id = match c.id {
            crate::sql::Auto::Set(v) => v,
            _ => 0,
        };
        Self {
            id,
            name: c.name,
            slug: c.slug,
            parent_id: c.parent_id,
            description: c.description,
            created_at: c.created_at,
        }
    }
}

#[derive(Debug, Deserialize)]
struct CreateTagBody {
    slug: String,
}

#[derive(Debug, Serialize)]
struct TagResponse {
    id: i64,
    name: String,
    slug: String,
}

impl From<MediaTag> for TagResponse {
    fn from(t: MediaTag) -> Self {
        let id = match t.id {
            crate::sql::Auto::Set(v) => v,
            _ => 0,
        };
        Self {
            id,
            name: t.name,
            slug: t.slug,
        }
    }
}

#[derive(Debug, Deserialize)]
struct PopularQuery {
    #[serde(default = "default_limit")]
    limit: i64,
}

#[derive(Debug, Deserialize)]
struct ListWithTagQuery {
    #[serde(default = "default_limit")]
    limit: i64,
    #[serde(default)]
    offset: i64,
}

fn default_limit() -> i64 {
    50
}

#[derive(Debug, Deserialize)]
struct ContentsQuery {
    #[serde(default)]
    recursive: bool,
}

// =====================================================================
// Error mapping
// =====================================================================

impl IntoResponse for MediaError {
    fn into_response(self) -> Response {
        let (status, msg) = match &self {
            MediaError::UnknownDisk(_) => (StatusCode::BAD_REQUEST, self.to_string()),
            MediaError::Storage(_) => (StatusCode::BAD_GATEWAY, self.to_string()),
            MediaError::Db(_) => (StatusCode::INTERNAL_SERVER_ERROR, self.to_string()),
            MediaError::Other(m) if m.contains("not found") => {
                (StatusCode::NOT_FOUND, self.to_string())
            }
            MediaError::Other(_) => (StatusCode::BAD_REQUEST, self.to_string()),
        };
        let body = serde_json::json!({"error": msg});
        (status, Json(body)).into_response()
    }
}

// =====================================================================
// Handlers
// =====================================================================

async fn begin_upload_handler(
    State(manager): State<Arc<MediaManager>>,
    Json(body): Json<BeginUploadBody>,
) -> Result<Json<UploadTicketBody>, MediaError> {
    let ticket = manager
        .begin_upload(UploadIntent {
            disk: body.disk,
            key_prefix: body.key_prefix,
            mime: body.mime,
            original_filename: body.original_filename,
            size_bytes: body.size_bytes,
            uploaded_by_id: body.uploaded_by_id,
            collection_id: body.collection_id,
            ttl: Duration::from_secs(body.ttl_secs.clamp(60, 3600)),
        })
        .await?;
    Ok(Json(UploadTicketBody {
        media_id: ticket.media_id,
        upload_url: ticket.upload_url,
        expires_at: ticket.expires_at,
        disk: ticket.disk,
        storage_key: ticket.storage_key,
    }))
}

async fn finalize_upload_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
) -> Result<Json<MediaResponse>, MediaError> {
    let m = manager.finalize_upload(id).await?;
    let resp = MediaResponse::from_row(&manager, m).await?;
    Ok(Json(resp))
}

async fn get_media_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
) -> Result<Json<MediaResponse>, MediaError> {
    let m = manager
        .get(id)
        .await?
        .ok_or_else(|| MediaError::Other(format!("media {id} not found")))?;
    let resp = MediaResponse::from_row(&manager, m).await?;
    Ok(Json(resp))
}

async fn delete_media_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
) -> Result<StatusCode, MediaError> {
    let m = manager
        .get(id)
        .await?
        .ok_or_else(|| MediaError::Other(format!("media {id} not found")))?;
    manager.delete(&m).await?;
    Ok(StatusCode::NO_CONTENT)
}

async fn move_media_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
    Json(body): Json<MoveBody>,
) -> Result<StatusCode, MediaError> {
    manager.move_to_collection(id, body.collection_id).await?;
    Ok(StatusCode::NO_CONTENT)
}

async fn set_tags_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
    Json(body): Json<SetTagsBody>,
) -> Result<StatusCode, MediaError> {
    let slugs: Vec<&str> = body.slugs.iter().map(String::as_str).collect();
    manager.set_tags(id, &slugs).await?;
    Ok(StatusCode::NO_CONTENT)
}

async fn untag_handler(
    State(manager): State<Arc<MediaManager>>,
    Path((id, slug)): Path<(i64, String)>,
) -> Result<StatusCode, MediaError> {
    manager.untag(id, &slug).await?;
    Ok(StatusCode::NO_CONTENT)
}

async fn create_collection_handler(
    State(manager): State<Arc<MediaManager>>,
    Json(body): Json<CreateCollectionBody>,
) -> Result<(StatusCode, Json<CollectionResponse>), MediaError> {
    let c = manager
        .create_collection(body.name, body.slug, body.parent_id, body.description)
        .await?;
    Ok((StatusCode::CREATED, Json(c.into())))
}

async fn list_collections_handler(
    State(manager): State<Arc<MediaManager>>,
) -> Result<Json<Vec<CollectionResponse>>, MediaError> {
    let cs = manager.list_collections().await?;
    Ok(Json(cs.into_iter().map(Into::into).collect()))
}

async fn get_collection_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
) -> Result<Json<CollectionResponse>, MediaError> {
    let c = manager
        .get_collection(id)
        .await?
        .ok_or_else(|| MediaError::Other(format!("collection {id} not found")))?;
    Ok(Json(c.into()))
}

async fn delete_collection_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
) -> Result<StatusCode, MediaError> {
    manager.delete_collection(id).await?;
    Ok(StatusCode::NO_CONTENT)
}

async fn collection_contents_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(id): Path<i64>,
    Query(q): Query<ContentsQuery>,
) -> Result<Json<Vec<MediaResponse>>, MediaError> {
    let media = manager.list_in_collection(id, q.recursive).await?;
    let mut out = Vec::with_capacity(media.len());
    for m in media {
        out.push(MediaResponse::from_row(&manager, m).await?);
    }
    Ok(Json(out))
}

async fn create_tag_handler(
    State(manager): State<Arc<MediaManager>>,
    Json(body): Json<CreateTagBody>,
) -> Result<(StatusCode, Json<TagResponse>), MediaError> {
    let t = manager.ensure_tag(&body.slug).await?;
    Ok((StatusCode::CREATED, Json(t.into())))
}

async fn list_tags_handler(
    State(manager): State<Arc<MediaManager>>,
) -> Result<Json<Vec<TagResponse>>, MediaError> {
    // No dedicated `list_all_tags` method on the manager — popular()
    // with a high limit covers the same ground, sorted by usage.
    let pairs = manager.popular_tags(1000).await?;
    Ok(Json(pairs.into_iter().map(|(t, _)| t.into()).collect()))
}

async fn popular_tags_handler(
    State(manager): State<Arc<MediaManager>>,
    Query(q): Query<PopularQuery>,
) -> Result<Json<Vec<PopularTagEntry>>, MediaError> {
    let pairs = manager.popular_tags(q.limit).await?;
    let resp = pairs
        .into_iter()
        .map(|(t, count)| PopularTagEntry {
            tag: t.into(),
            use_count: count,
        })
        .collect();
    Ok(Json(resp))
}

#[derive(Debug, Serialize)]
struct PopularTagEntry {
    #[serde(flatten)]
    tag: TagResponse,
    use_count: i64,
}

async fn media_with_tag_handler(
    State(manager): State<Arc<MediaManager>>,
    Path(slug): Path<String>,
    Query(q): Query<ListWithTagQuery>,
) -> Result<Json<Vec<MediaResponse>>, MediaError> {
    let rows = manager.list_with_tag(&slug, q.limit, q.offset).await?;
    let mut out = Vec::with_capacity(rows.len());
    for m in rows {
        out.push(MediaResponse::from_row(&manager, m).await?);
    }
    Ok(Json(out))
}

// Avoid an unused-import warning if MediaStatus isn't referenced
// elsewhere in the module after future trims.
#[allow(dead_code)]
fn _media_status_marker(_: MediaStatus) {}