class ProjectCard extends HTMLElement {
    static get observedAttributes() {
        return ['image', 'image-alt', 'title', 'description'];
    }

    constructor() {
        super();
        this.attachShadow({ mode: 'open' });
        this._rendered = false;
    }

    connectedCallback() {
        this._render();
    }

    attributeChangedCallback() {
        if (this._rendered) {
            this._render();
        }
    }

    _render() {
        this._rendered = true;
        const alt = this.getAttribute('image-alt') || '';
        const title = this.getAttribute('title') || '';
        const description = this.getAttribute('description') || '';

        this.shadowRoot.innerHTML = `
            <style>
                :host {
                    display: block;
                }
                .content-box {
                    background-color: var(--background-accent-clr, #324f4f);
                    margin: 50px 20px 20px;
                    padding: 20px;
                    border-radius: 20px;
                }
                .content-box p {
                    margin: 0;
                }
                .intro-text {
                    font-weight: bolder;
                    font-size: 28px;
                    color: var(--green-clr, #6ede9a);
                }
                .project-thumb {
                    width: 150px;
                    height: 150px;
                    object-fit: cover;
                    margin-right: 15px;
                    border-radius: 75px;
                    float: left;
                }
                ::slotted(p) { margin: 0; }
            </style>
            <div class="content-box">
                <img class="project-thumb" src="${this._escapeAttribute(this.getAttribute('image') || '')}" alt="${this._escapeAttribute(alt)}">
                <p><span class="intro-text"></span><slot></slot></p>
            </div>`;
        this.shadowRoot.querySelector('.intro-text').textContent = title;
        this._renderDescription(description);
    }

    _renderDescription(description) {
        const slot = this.shadowRoot.querySelector('slot');
        slot.textContent = '';
        const linkPattern = /\[\[([^|\]]+)\|([^\]]+)\]\]/g;
        let lastIndex = 0;
        let match;
        while ((match = linkPattern.exec(description)) !== null) {
            if (match.index > lastIndex) {
                slot.appendChild(document.createTextNode(description.slice(lastIndex, match.index)));
            }
            const link = document.createElement('a');
            link.href = match[2];
            link.textContent = match[1];
            if (match[2].startsWith('http')) {
                link.target = '_blank';
                link.rel = 'noopener';
            }
            slot.appendChild(link);
            lastIndex = match.index + match[0].length;
            if (linkPattern.lastIndex === match.index) {
                linkPattern.lastIndex++;
            }
        }
        if (lastIndex < description.length) {
            slot.appendChild(document.createTextNode(description.slice(lastIndex)));
        }
    }

    _escapeAttribute(value) {
        return value
            .replace(/&/g, '&amp;')
            .replace(/"/g, '&quot;')
            .replace(/</g, '&lt;');
    }
}

customElements.define('project-card', ProjectCard);