범용 영상 회전기 (단축키 전용).js

// ==UserScript==
// @name         범용 영상 회전기 (단축키 전용)
// @version      1.5
// @description  단축키(Ctrl+Shift+Alt+R)로 모든 웹사이트의 HTML5 영상을 90도씩 순차적으로 회전시킵니다.
// @author       Gemini
// @match        *://*/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    class VideoRotator {
        static #CONFIG = {
            ROTATION_STEPS: 4,
            ROTATION_ANGLE_DEGREES: 90,
            SHORTCUT_KEY: 'KeyR',
            VIDEO_SELECTORS: ['video:hover', 'video:not([paused])', 'video'],
            EDITABLE_TAGS: new Set(['INPUT', 'TEXTAREA']),
        };

        #rotationState = new WeakMap();

        constructor() {
            document.addEventListener('keydown', this.#handleKeyDown.bind(this), true);
        }

        #isShortcutPressed(e) {
            return e.code === VideoRotator.#CONFIG.SHORTCUT_KEY && e.ctrlKey && e.shiftKey && e.altKey;
        }

        #isTargetEditable(target) {
            return target.isContentEditable || VideoRotator.#CONFIG.EDITABLE_TAGS.has(target.tagName);
        }

        #findPrioritizedVideo() {
            for (const selector of VideoRotator.#CONFIG.VIDEO_SELECTORS) {
                const videoElement = document.querySelector(selector);
                if (videoElement) return videoElement;
            }
            return null;
        }

        #calculateTransform(step, video) {
            if (step === 0) return '';

            const angle = step * VideoRotator.#CONFIG.ROTATION_ANGLE_DEGREES;
            let transform = `rotate(${angle}deg)`;

            const isPortrait = step % 2 !== 0;
            if (isPortrait) {
                const { clientWidth, clientHeight } = video;
                if (clientWidth > 0 && clientHeight > 0) {
                    const scale = Math.min(clientWidth / clientHeight, clientHeight / clientWidth);
                    transform += ` scale(${scale})`;
                }
            }
            return transform;
        }

        #applyRotation(video) {
            const currentStep = this.#rotationState.get(video) ?? 0;
            const nextStep = (currentStep + 1) % VideoRotator.#CONFIG.ROTATION_STEPS;

            const transformStyle = this.#calculateTransform(nextStep, video);

            video.style.transform = transformStyle;
            video.style.willChange = transformStyle ? 'transform' : 'auto';

            if (nextStep === 0) {
                this.#rotationState.delete(video);
            } else {
                this.#rotationState.set(video, nextStep);
            }
        }

        #handleKeyDown(event) {
            if (!this.#isShortcutPressed(event) || this.#isTargetEditable(event.target)) {
                return;
            }

            event.preventDefault();
            event.stopPropagation();

            const targetVideo = this.#findPrioritizedVideo();
            if (targetVideo) {
                this.#applyRotation(targetVideo);
            }
        }
    }

    new VideoRotator();

})();