import { Icon, Text } from "design-system";
import { showIndicator } from "pages/Editor/GuidedTour/utils";
import React, { useContext, useEffect, useState } from "react";
import styled from "styled-components";
import { PADDING_HIGHLIGHT, getPosition } from "./utils";
import type {
  FeatureDetails,
  FeatureParams,
  OffsetType,
} from "./walkthroughContext";
import WalkthroughContext from "./walkthroughContext";
import AnalyticsUtil from "utils/AnalyticsUtil";

const CLIPID = "clip__feature";
const Z_INDEX = 1000;

const WalkthroughWrapper = styled.div`
  left: 0px;
  top: 0px;
  position: fixed;
  width: 100%;
  height: 100%;
  color: rgb(0, 0, 0, 0.7);
  z-index: ${Z_INDEX};
  // This allows the user to click on the target element rather than the overlay div
  pointer-events: none;
`;

const SvgWrapper = styled.svg`
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
`;

const InstructionsWrapper = styled.div`
  padding: var(--ads-v2-spaces-4);
  position: absolute;
  background: white;
  display: flex;
  flex-direction: column;
  width: 296px;
  pointer-events: auto;
  border-radius: var(--ads-radius-1);
`;

const ImageWrapper = styled.div`
  border-radius: var(--ads-radius-1);
  background: #f1f5f9;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 8px;
  padding: var(--ads-v2-spaces-7);
  img {
    max-height: 220px;
  }
`;

const InstructionsHeaderWrapper = styled.div`
  display: flex;
  p {
    flex-grow: 1;
  }
  span {
    align-self: flex-start;
    margin-top: 5px;
    cursor: pointer;
  }
`;

type RefRectParams = {
  // body params
  bh: number;
  bw: number;
  // target params
  th: number;
  tw: number;
  tx: number;
  ty: number;
};

/*
 * Clip Path Polygon :
 * 1) 0 0 ---->  (body start) (body start)
 * 2) 0 ${boundingRect.bh} ---->  (body start) (body end)
 * 3) ${boundingRect.tx} ${boundingRect.bh} ----> (target start) (body end)
 * 4) ${boundingRect.tx} ${boundingRect.ty} ----> (target start) (target start)
 * 5) ${boundingRect.tx + boundingRect.tw} ${boundingRect.ty} ----> (target end) (target start)
 * 6) ${boundingRect.tx + boundingRect.tw} ${boundingRect.ty + boundingRect.th} ----> (target end) (target end)
 * 7) ${boundingRect.tx} ${boundingRect.ty + boundingRect.th} ----> (target start) (target end)
 * 8) ${boundingRect.tx} ${boundingRect.bh} ----> (target start) (body end)
 * 9) ${boundingRect.bw} ${boundingRect.bh} ----> (body end) (body end)
 * 10) ${boundingRect.bw} 0 ----> (body end) (body start)
 *
 *
 *      1 ← ← ← ← ← ← ← ← ← ← ← ← ← ← ← ← ←10
 *      ↓                                   ↑
 *      ↓               Body                ↑
 *      ↓                                   ↑
 *      ↓                                   ↑
 *      ↓         4 → → → → → → → 5         ↑
 *      ↓         ↑ / / / / / / / ↓         ↑
 *      ↓         ↑ / / /Target/ /↓         ↑
 *      ↓         ↑ / / / / / / / ↓         ↑
 *      ↓         7 ← ← ← ← ← ← ← 6         ↑
 *      ↓         ↑↓                        ↑
 *      ↓         ↑↓                        ↑
 *      2 → → → → 3,8 → → → → → → → → → → → 9
 */

/**
 * Creates a Highlighting Clipping mask around a target container
 * @param targetId Id for the target container to show highlighting around it
 */

const WalkthroughRenderer = ({
  details,
  offset,
  onDismiss,
  targetId,
  eventParams = {},
}: FeatureParams) => {
  const [boundingRect, setBoundingRect] = useState<RefRectParams | null>(null);
  const { popFeature } = useContext(WalkthroughContext) || {};
  const updateBoundingRect = () => {
    const highlightArea = document.querySelector(`#${targetId}`);
    if (highlightArea) {
      const boundingRect = highlightArea.getBoundingClientRect();
      const bodyRect = document.body.getBoundingClientRect();
      const offsetHighlightPad =
        typeof offset?.highlightPad === "number"
          ? offset?.highlightPad
          : PADDING_HIGHLIGHT;
      setBoundingRect({
        bw: bodyRect.width,
        bh: bodyRect.height,
        tw: boundingRect.width + 2 * offsetHighlightPad,
        th: boundingRect.height + 2 * offsetHighlightPad,
        tx: boundingRect.x - offsetHighlightPad,
        ty: boundingRect.y - offsetHighlightPad,
      });
      showIndicator(`#${targetId}`, offset?.position, {
        top: offset?.indicatorTop || 0,
        left: offset?.indicatorLeft || 0,
        zIndex: Z_INDEX + 1,
      });
    }
  };

  useEffect(() => {
    updateBoundingRect();
    const highlightArea = document.querySelector(`#${targetId}`);
    window.addEventListener("resize", updateBoundingRect);
    const resizeObserver = new ResizeObserver(updateBoundingRect);
    if (highlightArea) {
      AnalyticsUtil.logEvent("WALKTHROUGH_SHOWN", eventParams);
      resizeObserver.observe(highlightArea);
    }
    return () => {
      window.removeEventListener("resize", updateBoundingRect);
      if (highlightArea) resizeObserver.unobserve(highlightArea);
    };
  }, [targetId]);

  const onDismissWalkthrough = () => {
    onDismiss && onDismiss();
    popFeature && popFeature();
  };

  if (!boundingRect) return null;

  return (
    <WalkthroughWrapper className="t--walkthrough-overlay">
      <SvgWrapper
        height={boundingRect.bh}
        width={boundingRect.bw}
        xmlns="http://www.w3.org/2000/svg"
      >
        <defs>
          <clipPath id={CLIPID}>
            <polygon
              // See the comments above the component declaration to understand the below points assignment.
              points={`
                0 0, 
                0 ${boundingRect.bh}, 
                ${boundingRect.tx} ${boundingRect.bh}, 
                ${boundingRect.tx} ${boundingRect.ty}, 
                ${boundingRect.tx + boundingRect.tw} ${boundingRect.ty},
                ${boundingRect.tx + boundingRect.tw} ${
                boundingRect.ty + boundingRect.th
              }, 
                ${boundingRect.tx} ${boundingRect.ty + boundingRect.th}, 
                ${boundingRect.tx} ${boundingRect.bh}, 
                ${boundingRect.bw} ${boundingRect.bh}, 
                ${boundingRect.bw} 0
              `}
            />
          </clipPath>
        </defs>
        <rect
          style={{
            clipPath: 'url("#' + CLIPID + '")',
            fill: "currentcolor",
            height: boundingRect.bh,
            pointerEvents: "auto",
            width: boundingRect.bw,
          }}
        />
      </SvgWrapper>
      <InstructionsComponent
        details={details}
        offset={offset}
        onClose={onDismissWalkthrough}
        targetId={targetId}
      />
    </WalkthroughWrapper>
  );
};

const InstructionsComponent = ({
  details,
  offset,
  onClose,
  targetId,
}: {
  details?: FeatureDetails;
  offset?: OffsetType;
  targetId: string;
  onClose: () => void;
}) => {
  if (!details) return null;

  const positionAttr = getPosition({
    targetId,
    offset,
  });

  return (
    <InstructionsWrapper style={{ ...positionAttr }}>
      <InstructionsHeaderWrapper>
        <Text kind="heading-s" renderAs="p">
          {details.title}
        </Text>
        <Icon name="close" onClick={onClose} size="md" />
      </InstructionsHeaderWrapper>
      <Text>{details.description}</Text>
      {details.imageURL && (
        <ImageWrapper>
          <img src={details.imageURL} />
        </ImageWrapper>
      )}
    </InstructionsWrapper>
  );
};

export default WalkthroughRenderer;