import { getDocument } from "svelte-toolbelt";
import { on } from "svelte/events";
import { watch } from "runed";
import { isElement } from "./is.js";
function isPointInPolygon(point, polygon) {
    const [x, y] = point;
    let isInside = false;
    const length = polygon.length;
    for (let i = 0, j = length - 1; i < length; j = i++) {
        const [xi, yi] = polygon[i] ?? [0, 0];
        const [xj, yj] = polygon[j] ?? [0, 0];
        const intersect = yi >= y !== yj >= y && x <= ((xj - xi) * (y - yi)) / (yj - yi) + xi;
        if (intersect) {
            isInside = !isInside;
        }
    }
    return isInside;
}
function isInsideRect(point, rect) {
    return (point[0] >= rect.left &&
        point[0] <= rect.right &&
        point[1] >= rect.top &&
        point[1] <= rect.bottom);
}
function getSide(triggerRect, contentRect) {
    // determine which side the content is on relative to trigger
    const triggerCenterX = triggerRect.left + triggerRect.width / 2;
    const triggerCenterY = triggerRect.top + triggerRect.height / 2;
    const contentCenterX = contentRect.left + contentRect.width / 2;
    const contentCenterY = contentRect.top + contentRect.height / 2;
    const deltaX = contentCenterX - triggerCenterX;
    const deltaY = contentCenterY - triggerCenterY;
    if (Math.abs(deltaX) > Math.abs(deltaY)) {
        return deltaX > 0 ? "right" : "left";
    }
    return deltaY > 0 ? "bottom" : "top";
}
/**
 * Creates a safe polygon area that allows users to move their cursor between
 * the trigger and floating content without closing it.
 */
export class SafePolygon {
    #opts;
    #buffer;
    // tracks the cursor position when leaving trigger or content
    #exitPoint = null;
    // tracks what we're moving toward: "content" when leaving trigger, "trigger" when leaving content
    #exitTarget = null;
    constructor(opts) {
        this.#opts = opts;
        this.#buffer = opts.buffer ?? 1;
        watch([opts.triggerNode, opts.contentNode, opts.enabled], ([triggerNode, contentNode, enabled]) => {
            if (!triggerNode || !contentNode || !enabled) {
                this.#exitPoint = null;
                this.#exitTarget = null;
                return;
            }
            const doc = getDocument(triggerNode);
            const handlePointerMove = (e) => {
                this.#onPointerMove(e, triggerNode, contentNode);
            };
            const handleTriggerLeave = (e) => {
                // when leaving trigger toward content, record exit point
                const target = e.relatedTarget;
                // if going directly to content, no need for polygon tracking
                if (isElement(target) && contentNode.contains(target)) {
                    return;
                }
                this.#exitPoint = [e.clientX, e.clientY];
                this.#exitTarget = "content";
            };
            const handleTriggerEnter = () => {
                // reached trigger, clear tracking
                this.#exitPoint = null;
                this.#exitTarget = null;
            };
            const handleContentEnter = () => {
                // reached content, clear tracking
                this.#exitPoint = null;
                this.#exitTarget = null;
            };
            const handleContentLeave = (e) => {
                // when leaving content, check if going directly back to trigger
                const target = e.relatedTarget;
                if (isElement(target) && triggerNode.contains(target)) {
                    // going directly to trigger, no polygon tracking needed
                    return;
                }
                // might be traversing gap back to trigger, set up polygon tracking
                this.#exitPoint = [e.clientX, e.clientY];
                this.#exitTarget = "trigger";
            };
            return [
                on(doc, "pointermove", handlePointerMove),
                on(triggerNode, "pointerleave", handleTriggerLeave),
                on(triggerNode, "pointerenter", handleTriggerEnter),
                on(contentNode, "pointerenter", handleContentEnter),
                on(contentNode, "pointerleave", handleContentLeave),
            ].reduce((acc, cleanup) => () => {
                acc();
                cleanup();
            }, () => { });
        });
    }
    #onPointerMove(e, triggerNode, contentNode) {
        // if no exit point recorded, nothing to check
        if (!this.#exitPoint || !this.#exitTarget)
            return;
        const clientPoint = [e.clientX, e.clientY];
        const triggerRect = triggerNode.getBoundingClientRect();
        const contentRect = contentNode.getBoundingClientRect();
        // check if pointer reached the target
        if (this.#exitTarget === "content" && isInsideRect(clientPoint, contentRect)) {
            this.#exitPoint = null;
            this.#exitTarget = null;
            return;
        }
        if (this.#exitTarget === "trigger" && isInsideRect(clientPoint, triggerRect)) {
            this.#exitPoint = null;
            this.#exitTarget = null;
            return;
        }
        // check if pointer is in the rectangular corridor between trigger and content
        const side = getSide(triggerRect, contentRect);
        const corridorPoly = this.#getCorridorPolygon(triggerRect, contentRect, side);
        if (corridorPoly && isPointInPolygon(clientPoint, corridorPoly)) {
            return;
        }
        // check if pointer is within the safe polygon from exit point to target
        const targetRect = this.#exitTarget === "content" ? contentRect : triggerRect;
        const safePoly = this.#getSafePolygon(this.#exitPoint, targetRect, side, this.#exitTarget);
        if (isPointInPolygon(clientPoint, safePoly)) {
            return;
        }
        // pointer is outside all safe zones - close
        this.#exitPoint = null;
        this.#exitTarget = null;
        this.#opts.onPointerExit();
    }
    /**
     * Creates a rectangular corridor between trigger and content
     * This prevents closing when cursor is in the gap between them
     */
    #getCorridorPolygon(triggerRect, contentRect, side) {
        const buffer = this.#buffer;
        switch (side) {
            case "top":
                return [
                    [Math.min(triggerRect.left, contentRect.left) - buffer, triggerRect.top],
                    [Math.min(triggerRect.left, contentRect.left) - buffer, contentRect.bottom],
                    [Math.max(triggerRect.right, contentRect.right) + buffer, contentRect.bottom],
                    [Math.max(triggerRect.right, contentRect.right) + buffer, triggerRect.top],
                ];
            case "bottom":
                return [
                    [Math.min(triggerRect.left, contentRect.left) - buffer, triggerRect.bottom],
                    [Math.min(triggerRect.left, contentRect.left) - buffer, contentRect.top],
                    [Math.max(triggerRect.right, contentRect.right) + buffer, contentRect.top],
                    [Math.max(triggerRect.right, contentRect.right) + buffer, triggerRect.bottom],
                ];
            case "left":
                return [
                    [triggerRect.left, Math.min(triggerRect.top, contentRect.top) - buffer],
                    [contentRect.right, Math.min(triggerRect.top, contentRect.top) - buffer],
                    [contentRect.right, Math.max(triggerRect.bottom, contentRect.bottom) + buffer],
                    [triggerRect.left, Math.max(triggerRect.bottom, contentRect.bottom) + buffer],
                ];
            case "right":
                return [
                    [triggerRect.right, Math.min(triggerRect.top, contentRect.top) - buffer],
                    [contentRect.left, Math.min(triggerRect.top, contentRect.top) - buffer],
                    [contentRect.left, Math.max(triggerRect.bottom, contentRect.bottom) + buffer],
                    [triggerRect.right, Math.max(triggerRect.bottom, contentRect.bottom) + buffer],
                ];
        }
    }
    /**
     * Creates a triangular/trapezoidal safe zone from the exit point to the target
     */
    #getSafePolygon(exitPoint, targetRect, side, exitTarget) {
        const buffer = this.#buffer * 4;
        const [x, y] = exitPoint;
        // when going back to trigger, we need to flip the side
        const effectiveSide = exitTarget === "trigger" ? this.#flipSide(side) : side;
        // create polygon points from cursor to target edges
        switch (effectiveSide) {
            case "top":
                return [
                    [x - buffer, y + buffer],
                    [x + buffer, y + buffer],
                    [targetRect.right + buffer, targetRect.bottom],
                    [targetRect.right + buffer, targetRect.top],
                    [targetRect.left - buffer, targetRect.top],
                    [targetRect.left - buffer, targetRect.bottom],
                ];
            case "bottom":
                return [
                    [x - buffer, y - buffer],
                    [x + buffer, y - buffer],
                    [targetRect.right + buffer, targetRect.top],
                    [targetRect.right + buffer, targetRect.bottom],
                    [targetRect.left - buffer, targetRect.bottom],
                    [targetRect.left - buffer, targetRect.top],
                ];
            case "left":
                return [
                    [x + buffer, y - buffer],
                    [x + buffer, y + buffer],
                    [targetRect.right, targetRect.bottom + buffer],
                    [targetRect.left, targetRect.bottom + buffer],
                    [targetRect.left, targetRect.top - buffer],
                    [targetRect.right, targetRect.top - buffer],
                ];
            case "right":
                return [
                    [x - buffer, y - buffer],
                    [x - buffer, y + buffer],
                    [targetRect.left, targetRect.bottom + buffer],
                    [targetRect.right, targetRect.bottom + buffer],
                    [targetRect.right, targetRect.top - buffer],
                    [targetRect.left, targetRect.top - buffer],
                ];
        }
    }
    #flipSide(side) {
        switch (side) {
            case "top":
                return "bottom";
            case "bottom":
                return "top";
            case "left":
                return "right";
            case "right":
                return "left";
        }
    }
}