//! TRACES: FR-CAT-7 | FR-UI-5 | NFR-P9
//! The collections sidebar, grid selection, and the drag between them.
//!
//! `dr_catalog::collections` owns the data rules — hierarchy, membership,
//! revisions, cycles. This module owns the *interaction*: what is selected,
//! what a drag is carrying, and where a release lands.
//!
//! # What this module does and does not own
//!
//! Slint's `DragArea`/`DropArea` own the *gesture* — pointer capture, the
//! threshold separating a click from a drag, arbitration against the grid's
//! Flickable, the image under the cursor, and hit-testing the release. So the
//! drop arrives already addressed to a collection, and nothing here tracks
//! pointer positions or guesses a target.
//!
//! What is left here is what Slint cannot know:
//!
//! - **the payload** — which images the drag carries, built from the selection
//!   at the moment the drag starts;
//! - **the spring** — a dwell timer that opens a collapsed collection so a
//!   nested child can be reached mid-drag, and closes again what the drag only
//!   passed over.
//!
//! An earlier version hand-rolled the whole gesture on `TouchArea` and did not
//! work, for a reason worth keeping: an interactive `Flickable` claims any drag
//! starting inside it for scrolling and cancels the child TouchArea's press, so
//! the drag could never leave the grid.
//!
//! # Selection
//!
//! Selection is by **catalog image id**, never by row index. The grid is a
//! window over the catalog (FR-CAT-4) and scrubbing replaces every row, so an
//! index-based selection would silently come to mean forty different
//! photographs after a scrub. Ids survive that; they also survive a rescan.
//!
//! # Split into one module per area (docs/dev/code-health.md CH-1)
//!
//! `controller` holds the running state and the pure drop/delete/release
//! decisions; `press` the click-and-release selection policy; `tree_sync`
//! rebuilding the sidebar and pushing catalog state into the grid; `drag` the
//! cursor bitmap and the spring; `trash` the soft delete; `wiring_grid` and
//! `wiring_tree` the callbacks, split in two because together they were the
//! largest single piece; and `rename_menu` creating, naming and the row's
//! context menu. `mod.rs` re-exports what the rest of the crate calls by
//! `collections_ui::` path, so nothing outside this module needs to change.

mod controller;
mod drag;
mod press;
mod rename_menu;
mod trash;
mod tree_sync;
mod wiring_grid;
mod wiring_tree;

pub use controller::CollectionsController;
pub use press::{cancel_press, commit_press, select_row};
pub use trash::refresh_trash;
pub use tree_sync::{refresh_tree, sync_badges, sync_selection};
pub use wiring_grid::wire;

/// Test-only helpers shared by more than one of this module's submodules.
///
/// `ids` was defined once in the pre-split file and called from tests all
/// over it — both the pure `decide_drop` tests in `controller` and the press
/// tests in `press`. Splitting the tests with the code they exercise left it
/// needed in both, so it lives here once instead of being copied.
#[cfg(test)]
pub(super) mod test_support {
    use dr_types::ImageId;

    pub(super) fn ids(n: u64) -> Vec<ImageId> {
        (1..=n).map(ImageId).collect()
    }
}