/** @odoo-module **/

import { patch } from "@web/core/utils/patch";
import { PDFIframe } from "@sign/components/sign_request/PDF_iframe";

patch(PDFIframe.prototype, {
    enableCustom(signItem) {
        super.enableCustom(signItem);
        if (signItem.data.type === 'image') {
            const el = signItem.el;
            const data = signItem.data;
            
            // Add data-type attribute for CSS targeting
            el.setAttribute('data-type', 'image');

            // Function to adjust font size based on container dimensions
            const adjustFontSize = () => {
                const placeholder = el.querySelector('.o_placeholder');
                if (placeholder) {
                    const containerHeight = el.offsetHeight;
                    const containerWidth = el.offsetWidth;
                    const minDimension = Math.min(containerHeight, containerWidth);
                    const fontSize = Math.max(10, Math.min(16, minDimension * 0.4));
                    placeholder.style.fontSize = fontSize + 'px !important';
                    placeholder.style.lineHeight = '1';
                }
            };

            // Initial font size adjustment
            setTimeout(adjustFontSize, 100);

            // Watch for size changes
            if (window.ResizeObserver) {
                const resizeObserver = new ResizeObserver(adjustFontSize);
                resizeObserver.observe(el);
            }

            const input = el.querySelector('.o_sign_image_upload_input');
            if (input) {
                el.addEventListener('click', (e) => {
                    if (this.readonly || (data.responsible > 0 && data.responsible !== this.currentRole)) return;
                    // Prevent recursive click if clicking the input itself bubbles up
                    if (e.target !== input) {
                        input.click();
                    }
                });

                input.addEventListener('change', (e) => {
                    const file = e.target.files[0];
                    if (!file) return;

                    const reader = new FileReader();
                    reader.onload = (readerEvent) => {
                        const img = new Image();
                        img.onload = () => {
                            const canvas = document.createElement('canvas');
                            let width = img.width;
                            let height = img.height;

                            const MAX_SIZE = 1080;
                            if (width > height) {
                                if (width > MAX_SIZE) {
                                    height *= MAX_SIZE / width;
                                    width = MAX_SIZE;
                                }
                            } else {
                                if (height > MAX_SIZE) {
                                    width *= MAX_SIZE / height;
                                    height = MAX_SIZE;
                                }
                            }

                            canvas.width = width;
                            canvas.height = height;

                            const ctx = canvas.getContext('2d');
                            ctx.drawImage(img, 0, 0, width, height);

                            const compressedDataUrl = canvas.toDataURL('image/jpeg', 0.7);

                            // Update state and element
                            data.value = compressedDataUrl;
                            el.dataset.value = compressedDataUrl;

                            // Force immediate display update
                            const placeholder = el.querySelector('.o_placeholder');
                            if (placeholder) placeholder.remove();

                            let existingImg = el.querySelector('img');
                            if (!existingImg) {
                                existingImg = document.createElement('img');
                                existingImg.style.maxWidth = '100%';
                                existingImg.style.maxHeight = '100%';
                                existingImg.style.objectFit = 'contain';
                                const body = el.querySelector('.sign_item_body') || el;
                                body.appendChild(existingImg);
                            }
                            existingImg.src = compressedDataUrl;

                            // Notify Odoo of the value change
                            if (this.handleInput) {
                                this.handleInput();
                            }
                        };
                        img.src = readerEvent.target.result;
                    };
                    reader.readAsDataURL(file);
                });
            }

            // Performance Fix: Trigger lazy load if already visible
            this._triggerLazyLoad(el);
        }
    },

    refreshSignItemsForPage(page) {
        super.refreshSignItemsForPage(page);
        if (this.signItems && this.signItems[page]) {
            for (const id in this.signItems[page]) {
                const item = this.signItems[page][id];
                if (item && item.el) {
                    this._triggerLazyLoad(item.el);
                }
            }
        }
    },

    /**
     * Triggers the load of a lazy-loaded image if it has a data-src attribute
     * @param {HTMLElement} el 
     */
    _triggerLazyLoad(el) {
        if (!el) return;
        const lazyImg = el.querySelector('.o_sign_image_lazy');
        if (lazyImg && lazyImg.dataset.src) {
            const currentSrc = lazyImg.getAttribute('src');
            // If src is still the transparent placeholder gif or empty, load the real image
            if (!currentSrc || currentSrc.startsWith('data:image/gif')) {
                lazyImg.src = lazyImg.dataset.src;
                lazyImg.onload = () => {
                    lazyImg.classList.remove('o_sign_image_loading');
                    el.classList.remove('o_sign_image_loading_container');
                    lazyImg.style.opacity = 1;
                };
            }
        }
    },

    getSignatureValueFromElement(item) {
        if (item.data.type === 'image') {
            return item.el.dataset.value || item.data.value || false;
        }
        return super.getSignatureValueFromElement(item);
    }
});