import { Image } from "../../../image";
import { YBand, Rect } from "../../isomorphic/geometry";
import type { CaptureSpec } from "../../client-scripts/screen-shooter/types";
export declare class CompositeImage {
    private _captureAreaSize;
    private _compositeChunks;
    private _debugTmpDir;
    /** Creates a composite renderer instance while preserving subclass construction. */
    static create(...args: ConstructorParameters<typeof CompositeImage>): CompositeImage;
    /** Initializes chunk storage and an optional debug-output directory. */
    constructor();
    /**
     * Registers a viewport image with corresponding safe area, capture bounding rects and ignore bounding rects, all relative to the viewport.
     * The order of registration can be arbitrary, viewport height can change between chunks, gaps will be handled gracefully.
     * Expects finite integer coords and sizes, otherwise behavior is undefined.
     * @throws {Error} if capture area size is zero or negative
     */
    registerViewportImageAtOffset(viewportImage: Image, safeArea: YBand<"viewport", "device">, captureSpecs: CaptureSpec<"viewport", "device">[], ignoreBoundingRects: Rect<"viewport", "device">[], anchorShift?: number | null): Promise<void>;
    /**
     * Renders a composite image from the registered chunks.
     * @throws {Error} if trying to render with zero chunks registered
     * @throws {Error} if any of the chunks contain malformed PNG data
     */
    render(): Promise<Image>;
    /**
     * Computes anchor tops for all chunks.
     *
     * The reference chunk is the one with the highest captureSpec covering-rect top (= the first
     * scroll position, which has the most positive viewport-space top).
     *
     * For each non-reference chunk the base anchorTop is computed from captureSpec deltas (same as
     * before). When per-chunk correction data is available, the anchor is additionally corrected.
     *
     *   anchorTop_corrected = anchorTop_from_specs + (chunkAnchorShift - referenceAnchorShift)
     *
     * In the stable case correction values are 0 for all chunks.
     */
    private _computeAnchoredChunks;
    /** Checks whether a capture spec contributes visible pixels in the current chunk. */
    private _isRenderableCaptureSpec;
    /** Returns the bounding rect that covers all visible capture-spec parts for a chunk. */
    private _getVisibleCoveringRect;
    /** Builds a segment candidate, listing all possible options, e.g. strictly follow safe area, relax top/bottom edges, ignore safe area at all. */
    private _buildCandidate;
    /** Computes a usable vertical band for a specific mode: e.g. what if we expand the top edge of the safe area? */
    private _getYBandForMode;
    /** Chooses the best vertical band per chunk, relaxing edges only where needed to avoid gaps. */
    private _chooseBestCandidates;
    /** Expansion for cases when capture elements are far apart and not fit one viewport. */
    private _expandCandidatesToFullArea;
    /** Checks whether visible capture-spec pixels cover the complete requested capture area. */
    private _doesVisibleAreaCoverFullArea;
    /** Given a list of best possible segments, builds a list of image pieces, inserting gaps when needed,
     * ensuring resulting array is a vertically continuous sequence of pieces. */
    private _buildRenderPieces;
    /** Fills an uncovered capture-area gap with usable chunk areas or black fallback slices. */
    private _buildGapPieces;
    /** Returns the horizontal viewport band occupied by visible capture-spec pixels. */
    private _getChunkHorizontalArea;
    /** Computes a shared horizontal crop band when chunks cannot safely use the original width. */
    private _computeCommonHorizontalAreaIfNeeded;
    /** Selects the horizontal band that should be used for a candidate chunk. */
    private _getCandidateHorizontalArea;
    /** Computes a horizontal band for expanded chunks using requested full rects and clip bounds. */
    private _getExpandedChunkHorizontalArea;
    /** Crops one viewport chunk into a render piece after clearing ignored regions. */
    private _createChunkPiece;
    /** Creates a black fallback image piece for areas that no chunk can provide. */
    private _createBlackPiece;
}