import type { Curve } from 'flo-boolean';


/** @internal */
interface Debug {
    /** Generated by debug object for later inspection */
    elems: Elems;
    timing: Timing;

    /**
     * These functions are meant to be used in the console, e.g. in the 
     * console try typing d.fs.twoProng.traceConvergence(0);
     */
    fs: {};
    directives: Directives;
}


/**
 * Elements generated during `findMats` for later inspection (only available
 * if debug has been enabled via `enableDebugForMat(true)`).
 *
 * The arrays are reset at the start of each `findMats` call and accumulate
 * over all MATs found in that call, one entry per boundary bezier curve in the
 * order the curves are encountered.
 */
interface Elems {
    /** The loose (axis-aligned) bounding box of each boundary bezier curve */
    readonly looseBoundingBoxes: number[][][];
    /** The tight (rotated) bounding box of each boundary bezier curve */
    readonly tightBoundingBoxes: number[][][];
    /** The bounding hull of each boundary bezier curve */
    readonly boundingHulls: number[][][];
    /** The curves whose end point forms a quite sharp corner with the next curve */
    readonly sharpCorners: Curve[];
    /** The curves whose end point forms a quite dull corner with the next curve */
    readonly dullCorners: Curve[];
}


/** @internal */
interface Timing {
    holeClosers: number;
    oneAnd2Prongs: number;
    threeProngs: number;
    sats: number;
    simplifyMat: number;
}


/** @internal */
interface Directives {
    stopAfterHoleClosers: boolean,
    stopAfterHoleClosersNum: number,
    stopAfterTwoProngs: boolean,
    stopAfterTwoProngsNum: number,
    stopAfterThreeProngs: boolean,
    stopAfterThreeProngsNum: number,
}


/** Returns a fresh (empty) set of debug `Elems`. */
function createEmptyElems(): Elems {
    return {
        looseBoundingBoxes: [],
        tightBoundingBoxes: [],
        boundingHulls: [],
        sharpCorners: [],
        dullCorners: []
    };
}


function enableDebugForMat(debugOn: boolean) {
    if (!debugOn) { 
        (globalThis as any)._debug_ = undefined; 
        return;
    }

    let debug: Debug = (globalThis as any)._debug_;

    debug = { 
        ...debug, 
        elems: { 
            ...debug?.elems,
            ...createEmptyElems()
        },
        timing: {
            ...debug?.timing,
            holeClosers: 0,
            oneAnd2Prongs: 0,
            threeProngs: 0,
            sats: 0,
            simplifyMat: 0
        },
        fs: {
            ...debug?.fs
        },
        directives: {
            //...debug?.directives,
            ...debug?.directives,
            stopAfterHoleClosers: false,
            stopAfterHoleClosersNum: undefined!,
            stopAfterTwoProngs: false,
            stopAfterTwoProngsNum: undefined!,
            stopAfterThreeProngs: false,
            stopAfterThreeProngsNum: undefined!,
        }
    };

    (globalThis as any)._debug_ = debug;
}


export type { Debug, Elems, Timing, Directives }
export { enableDebugForMat, createEmptyElems }