/**
 * Layout Renderer Module
 * Renders calculated paragraph layouts into the DOM with proper animations
 */
import { BaseModule } from './base-module.js';

class LayoutRendererModule extends BaseModule {
    constructor() {
        super('layout-renderer', 'Layout Renderer');
        
        // Module dependencies
        this.dependencies = [];
        
        // Configuration
        this.updateConfig({
            animation: {
                defaultSpeed: 1.0,
                wordAnimationClass: 'animate-word'
            }
        });
        
        // Bind methods
        this.bindMethods([
            'renderParagraph',
            'initializeContainers',
            'adjustJustification',
            'decorateInlineWord',
            'applyGlossaryEntries',
            'normalizeGlossaryText',
            'decorateGlossaryWord',
            'ensureGlossaryTooltip',
            'showGlossaryTooltip',
            'hideGlossaryTooltip',
            'positionGlossaryTooltip',
            'escapeRegExp'
        ]);
    }
    
    /**
     * Initialize the module
     * @returns {Promise<boolean>} - Resolves with success status
     */
    async initialize() {
        try {
            this.reportProgress(10, "Initializing Layout Renderer");
            this.reportProgress(100, "Layout Renderer ready");
            return true;
        } catch (error) {
            console.error("Error initializing Layout Renderer:", error);
            return false;
        }
    }
    
    /**
     * Initialize default containers
     */
    initializeContainers() {
        // Check if story container exists
        const storyContainer = document.getElementById('story');
        if (!storyContainer) {
            console.log('Story container not found, creating it');
            const container = document.createElement('div');
            container.id = 'story';
            document.body.appendChild(container);
        }
    }
    
    /**
     * Render a paragraph from layout data (pure DOM creation, no animation)
     * @param {Object} layoutData - Layout data containing breaks, nodes, and measures
     * @param {Object} options - Rendering options
     * @returns {HTMLElement} - The created paragraph element
     */
    renderParagraph(layoutData, options = {}) {
        const { id = `p-${Date.now()}` } = options;
        const { breaks, nodes, measures, fontSize, fontFamily, lineHeightPx } = layoutData;
        
        if (!breaks || !nodes) {
            console.error('LayoutRenderer: Invalid layout data');
            return null;
        }

        // Create paragraph container
        const paragraph = document.createElement('p');
        paragraph.id = id;
        paragraph.className = [
            layoutData.role ? `story-${layoutData.role}` : '',
            layoutData.addTopSpace ? 'story-textblock-start' : '',
            layoutData.dropCap ? 'story-dropcap-paragraph' : ''
        ].filter(Boolean).join(' ');
        paragraph.style.position = 'absolute';
        paragraph.style.margin = '0';
        paragraph.style.left = '0';
        const globalLineStart = Math.max(0, Number(layoutData.lineStart || 0));
        const windowOriginLine = Math.max(0, Number(layoutData.windowOriginLine || 0));
        paragraph.style.top = `${(globalLineStart - windowOriginLine) * Number(lineHeightPx || 0)}px`;
        if (fontSize) paragraph.style.fontSize = fontSize;
        if (fontFamily) paragraph.style.fontFamily = fontFamily;
        // Calculate paragraph height
        const storyElement = document.getElementById('story');
        if (!storyElement) {
            console.error('LayoutRenderer: Story container not found');
            return null;
        }

        const pageWidth = Number(layoutData.pageWidth || storyElement.clientWidth);
        paragraph.style.width = `${pageWidth}px`;
        paragraph.style.maxWidth = '100%';

        if (!Number.isFinite(Number(lineHeightPx)) || Number(lineHeightPx) <= 0) {
            throw new Error('LayoutRenderer: Missing canonical lineHeightPx for story layout.');
        }
        const lineHeight = Number(lineHeightPx);
        const contentTopLines = Math.max(0, Number(layoutData.contentTopLines || 0));
        const maxLineWidth = Array.isArray(measures) && measures.length > 0
            ? Math.max(pageWidth, ...measures)
            : pageWidth;
        // Height should include all lines (breaks.length represents number of lines)
        const numLines = Math.max(1, breaks.length - 1);
        const totalLines = Math.max(1, Number(layoutData.lineCount || (numLines + contentTopLines)));
        paragraph.style.height = `${lineHeight * totalLines}px`;
        paragraph.dataset.heightLines = String(totalLines);
        paragraph.dataset.lineStart = String(globalLineStart);
        paragraph.dataset.lineCount = String(totalLines);

        console.log(`LayoutRenderer: Rendering paragraph ${id} - ${breaks.length} breaks (${numLines} lines), lineHeight: ${lineHeight}px, total height: ${lineHeight * numLines}px`);

        // Debug: log break ratios
        breaks.forEach((brk, idx) => {
            if (idx > 0) {
                console.log(`  Line ${idx - 1}: break position ${brk.position}, ratio ${brk.ratio ? brk.ratio.toFixed(3) : 'undefined'}`);
            }
        });

        if (layoutData.dropCap && layoutData.dropCapText) {
            const dropCap = document.createElement('span');
            dropCap.className = 'drop-cap story-drop-cap';
            dropCap.textContent = layoutData.dropCapText;
            dropCap.style.top = `${contentTopLines * lineHeight}px`;
            paragraph.appendChild(dropCap);
        }

        if (Array.isArray(layoutData.lines) && layoutData.lines.length > 0) {
            layoutData.lines.forEach((line, lineIndex) => {
                this.renderLine({
                    paragraph,
                    line,
                    lineIndex,
                    contentTopLines,
                    lineHeight,
                    maxLineWidth
                });
            });
            this.applyGlossaryEntries(paragraph, layoutData.glossaryEntries);
            return paragraph;
        }

        // Position words according to layout with proper justification
        let wordCount = 0;
        let lastChild = null;
        let syllable = "";
        const stack = [paragraph];

        for (let i = 1; i < breaks.length; i++) {
            const lineIndex = i - 1;
            const lineWidth = measures[Math.min(lineIndex, measures.length - 1)];
            const currentBreak = breaks[i];
            const isFinalLine = i === breaks.length - 1;
            const isCentered = layoutData.align === 'center' ||
                layoutData.role === 'chapter-heading' ||
                layoutData.role === 'section-heading';
            const ratio = (isFinalLine || isCentered) ? 0 : (currentBreak.ratio || 0);
            const naturalLineWidth = isCentered
                ? this.measureNaturalLineWidth(nodes, breaks[i - 1].position, currentBreak.position)
                : lineWidth;
            const lineOffset = isCentered
                ? Math.max(0, (maxLineWidth - naturalLineWidth) / 2)
                : Array.isArray(layoutData.lineOffsets)
                    ? (layoutData.lineOffsets[Math.min(lineIndex, layoutData.lineOffsets.length - 1)] || 0)
                    : maxLineWidth - lineWidth;

            let currentLeft = 0;
            lastChild = null;

            // Iterate through nodes on this line (break positions are inclusive)
            for (let j = breaks[i-1].position; j <= currentBreak.position; j++) {
                const node = nodes[j];

                if (node.type === 'box' && node.value !== '' && j < currentBreak.position) {
                    const followsGlue = j > 0 && nodes[j - 1].type === 'glue';
                    const isTrailingPunctuation = /^[,.;:!?…)]$/.test(node.value) && !followsGlue;

                    // Check if this box follows a penalty (hyphenation point)
                    if (lastChild && isTrailingPunctuation) {
                        syllable += node.value;
                        lastChild.innerHTML = syllable;
                        this.decorateInlineWord(lastChild, stack);
                        currentLeft += node.width;
                    } else if (j > breaks[i-1].position + 1 &&
                        nodes[j-1].type === 'penalty' &&
                        lastChild) {
                        // Combine with previous syllable using zero-width non-joiner
                        syllable += '\u200c' + node.value;
                        lastChild.innerHTML = syllable;
                        this.decorateInlineWord(lastChild, stack);
                        currentLeft += node.width;
                    } else {
                        // Create new word span
                        const word = document.createElement('span');
                        word.className = 'word';
                        word.style.position = 'absolute';
                        word.style.display = 'inline-block';
                        word.style.whiteSpace = 'nowrap';
                        word.dataset.line = String(lineIndex);
                        word.dataset.lineStart = String(lineOffset);
                        word.dataset.lineWidth = String(lineWidth);

                        // Calculate position with proper line and justification
                        const topPercent = ((contentTopLines + lineIndex) * lineHeight * 100) / parseFloat(paragraph.style.height);
                        const leftPercent = ((lineOffset + currentLeft) * 100) / maxLineWidth;

                        word.style.top = `${topPercent}%`;
                        word.style.left = `${leftPercent}%`;
                        word.style.opacity = '0'; // Hidden until animated
                        word.style.visibility = 'hidden';
                        word.style.clipPath = 'inset(0 100% 0 0)';
                        syllable = node.value;
                        word.innerHTML = syllable;
                        this.decorateInlineWord(word, stack);
                        lastChild = word;

                        if (wordCount < 5 || (wordCount % 20 === 0)) {
                            console.log(`  Word ${wordCount} "${node.value}" at line ${lineIndex}, top: ${topPercent.toFixed(1)}%, left: ${leftPercent.toFixed(1)}%`);
                        }
                        wordCount++;

                        stack[stack.length - 1].appendChild(word);
                        currentLeft += node.width;
                    }

                } else if (node.type === 'tag') {
                    if (node.value.substr(0, 2) === '</') {
                        if (stack.length > 1) stack.pop();
                    } else {
                        const template = document.createElement('div');
                        template.innerHTML = node.value;
                        const tag = template.firstChild;
                        if (tag) {
                            tag.style.display = 'contents';
                            stack[stack.length - 1].appendChild(tag);
                            stack.push(tag);
                        }
                    }

                } else if (node.type === 'glue' && j > breaks[i-1].position && node.width !== 0 && j <= currentBreak.position) {
                    // Apply justification: adjust glue width based on line's ratio
                    let adjustedWidth = node.width;

                    if (ratio > 0) {
                        // Line needs stretching
                        adjustedWidth = node.width + (node.stretch * ratio);
                    } else if (ratio < 0) {
                        // Line needs shrinking
                        adjustedWidth = node.width + (node.shrink * ratio);
                    }
                    // If ratio === 0, line fits perfectly, use natural width

                    if (wordCount < 3) {
                        // Debug first line's glue adjustments
                        console.log(`    Glue at position ${j}: natural=${node.width.toFixed(2)}px, adjusted=${adjustedWidth.toFixed(2)}px, ratio=${ratio.toFixed(3)}, left before: ${currentLeft.toFixed(2)}px`);
                    }

                    // Increment position by the adjusted glue width
                    currentLeft += adjustedWidth;

                } else if (node.type === 'penalty' && node.penalty === 100 && j === currentBreak.position) {
                    // Add hyphen at line break
                    if (lastChild) {
                        lastChild.innerHTML = `${lastChild.innerHTML}-`;
                        continue;
                    }

                    const word = document.createElement('span');
                    word.className = 'word';
                    word.style.position = 'absolute';
                    word.style.display = 'inline-block';
                    word.style.whiteSpace = 'nowrap';
                    word.dataset.line = String(lineIndex);
                    word.dataset.lineStart = String(lineOffset);
                    word.dataset.lineWidth = String(lineWidth);
                    const topPercent = ((contentTopLines + lineIndex) * lineHeight * 100) / parseFloat(paragraph.style.height);
                    const leftPercent = ((lineOffset + currentLeft) * 100) / maxLineWidth;
                    word.style.top = `${topPercent}%`;
                    word.style.left = `${leftPercent}%`;
                    word.style.opacity = '0';
                    word.style.visibility = 'hidden';
                    word.style.clipPath = 'inset(0 100% 0 0)';
                    word.innerHTML = "-";
                    this.decorateInlineWord(word, stack);
                    stack[stack.length - 1].appendChild(word);
                }
            }
        }

        this.applyGlossaryEntries(paragraph, layoutData.glossaryEntries);
        return paragraph;
    }

    decorateInlineWord(word, stack = []) {
        if (!word || !Array.isArray(stack)) return;

        const glossaryElement = stack
            .slice()
            .reverse()
            .find(element => element?.classList?.contains('story-glossary-term'));
        if (!glossaryElement) return;

        const definition = glossaryElement.dataset.glossary || glossaryElement.getAttribute('title') || '';
        word.classList.add('story-glossary-word');
        word.dataset.glossary = definition;
        word.removeAttribute('title');
        word.tabIndex = 0;
        word.setAttribute('aria-label', `${word.textContent}: ${definition}`);
    }

    applyGlossaryEntries(paragraph, entries = []) {
        if (!paragraph || !Array.isArray(entries) || entries.length === 0) return;

        const words = Array.from(paragraph.querySelectorAll('.word'))
            .map(element => ({
                element,
                text: this.normalizeGlossaryText(element.textContent || '')
            }))
            .filter(word => word.text.length > 0 && word.text !== '-');

        if (words.length === 0) return;

        let cursor = 0;
        const segments = [];
        const fullText = words.map((word, index) => {
            if (index > 0) cursor += 1;
            const start = cursor;
            cursor += word.text.length;
            segments.push({ ...word, start, end: cursor });
            return word.text;
        }).join(' ');

        entries
            .filter(entry => entry && entry.term && entry.definition)
            .forEach(entry => {
                const normalizedTerm = this.normalizeGlossaryText(entry.term);
                if (!normalizedTerm) return;

                const matcher = new RegExp(`(^|\\s)(${this.escapeRegExp(normalizedTerm)})(?=\\s|$|[.,;:!?])`, 'giu');
                let match;
                while ((match = matcher.exec(fullText)) !== null) {
                    const matchStart = match.index + match[1].length;
                    const matchEnd = matchStart + match[2].length;
                    segments
                        .filter(segment => segment.end > matchStart && segment.start < matchEnd)
                        .forEach(segment => this.decorateGlossaryWord(segment.element, entry));
                }
            });
    }

    normalizeGlossaryText(text) {
        return String(text || '')
            .replace(/\u200c/g, '')
            .replace(/\u00ad/g, '')
            .replace(/-\s*$/g, '')
            .replace(/\s+/g, ' ')
            .trim();
    }

    decorateGlossaryWord(word, entry) {
        if (!word || !entry?.definition) return;
        word.classList.add('story-glossary-word');
        word.dataset.glossaryTerm = entry.term || this.normalizeGlossaryText(word.textContent || '');
        word.dataset.glossary = entry.definition;
        word.removeAttribute('title');
        word.tabIndex = 0;
        word.setAttribute('aria-label', `${this.normalizeGlossaryText(word.textContent || '')}: ${entry.definition}`);
        if (word.dataset.glossaryBound === 'true') return;
        word.dataset.glossaryBound = 'true';
        word.addEventListener('mouseenter', this.showGlossaryTooltip);
        word.addEventListener('focus', this.showGlossaryTooltip);
        word.addEventListener('mousemove', this.positionGlossaryTooltip);
        word.addEventListener('mouseleave', this.hideGlossaryTooltip);
        word.addEventListener('blur', this.hideGlossaryTooltip);
    }

    ensureGlossaryTooltip() {
        let tooltip = document.getElementById('story_glossary_tooltip');
        if (tooltip) return tooltip;

        tooltip = document.createElement('div');
        tooltip.id = 'story_glossary_tooltip';
        tooltip.className = 'story-glossary-tooltip';
        tooltip.setAttribute('role', 'tooltip');
        tooltip.setAttribute('aria-hidden', 'true');

        const header = document.createElement('div');
        header.className = 'story-glossary-tooltip-header';
        const title = document.createElement('h2');
        title.className = 'story-glossary-tooltip-title';
        header.appendChild(title);

        const body = document.createElement('div');
        body.className = 'story-glossary-tooltip-body';

        tooltip.append(header, body);
        document.body.appendChild(tooltip);
        return tooltip;
    }

    showGlossaryTooltip(event) {
        const word = event.currentTarget;
        if (!word) return;
        const tooltip = this.ensureGlossaryTooltip();
        const title = tooltip.querySelector('.story-glossary-tooltip-title');
        const body = tooltip.querySelector('.story-glossary-tooltip-body');
        if (title) title.textContent = word.dataset.glossaryTerm || this.normalizeGlossaryText(word.textContent || '');
        if (body) body.textContent = word.dataset.glossary || '';
        tooltip.dataset.anchorId = word.id || '';
        tooltip.__anchorElement = word;
        tooltip.classList.add('visible');
        tooltip.setAttribute('aria-hidden', 'false');
        this.positionGlossaryTooltip(event);
    }

    hideGlossaryTooltip() {
        const tooltip = document.getElementById('story_glossary_tooltip');
        if (!tooltip) return;
        tooltip.classList.remove('visible');
        tooltip.setAttribute('aria-hidden', 'true');
        tooltip.__anchorElement = null;
    }

    positionGlossaryTooltip(event) {
        const tooltip = document.getElementById('story_glossary_tooltip');
        if (!tooltip || !tooltip.classList.contains('visible')) return;

        const anchor = event?.currentTarget || tooltip.__anchorElement;
        if (!anchor || typeof anchor.getBoundingClientRect !== 'function') return;

        const anchorRect = anchor.getBoundingClientRect();
        const margin = Math.max(8, window.innerWidth * 0.006);
        const tooltipRect = tooltip.getBoundingClientRect();
        const preferredLeft = anchorRect.left + (anchorRect.width / 2) - (tooltipRect.width / 2);
        let left = Math.min(
            Math.max(margin, preferredLeft),
            Math.max(margin, window.innerWidth - tooltipRect.width - margin)
        );
        let top = anchorRect.top - tooltipRect.height - margin;
        if (top < margin) {
            top = anchorRect.bottom + margin;
        }
        top = Math.min(
            Math.max(margin, top),
            Math.max(margin, window.innerHeight - tooltipRect.height - margin)
        );

        tooltip.style.left = `${left}px`;
        tooltip.style.top = `${top}px`;
    }

    escapeRegExp(value) {
        return String(value).replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
    }

    renderLine({ paragraph, line, lineIndex, contentTopLines, lineHeight, maxLineWidth }) {
        const lineWidth = Number(line.measure || maxLineWidth);
        const lineOffset = Number(line.offset || 0);
        const ratio = line.isFinal ? 0 : Number(line.ratio || 0);
        const stack = [paragraph];
        let currentLeft = 0;
        let lastChild = null;
        let syllable = '';

        for (let j = 0; j < line.nodes.length; j += 1) {
            const node = line.nodes[j];
            if (!node) continue;

            if (node.type === 'box' && node.value !== '') {
                const followsGlue = j > 0 && line.nodes[j - 1].type === 'glue';
                const isTrailingPunctuation = /^[,.;:!?…)]$/.test(node.value) && !followsGlue;

                if (lastChild && isTrailingPunctuation) {
                    syllable += node.value;
                    lastChild.innerHTML = syllable;
                    this.decorateInlineWord(lastChild, stack);
                    currentLeft += node.width || 0;
                    continue;
                }

                const word = document.createElement('span');
                word.className = ['word', line.styleClass || ''].filter(Boolean).join(' ');
                word.style.position = 'absolute';
                word.style.display = 'inline-block';
                word.style.whiteSpace = 'nowrap';
                word.dataset.line = String(lineIndex);
                word.dataset.lineStart = String(lineOffset);
                word.dataset.lineWidth = String(lineWidth);
                word.style.top = `${((contentTopLines + lineIndex) * lineHeight * 100) / parseFloat(paragraph.style.height)}%`;
                word.style.left = `${((lineOffset + currentLeft) * 100) / maxLineWidth}%`;
                word.style.opacity = '0';
                word.style.visibility = 'hidden';
                word.style.clipPath = 'inset(0 100% 0 0)';
                syllable = node.value;
                word.innerHTML = syllable;
                this.decorateInlineWord(word, stack);
                stack[stack.length - 1].appendChild(word);
                lastChild = word;
                currentLeft += node.width || 0;
            } else if (node.type === 'tag') {
                if (String(node.value || '').startsWith('</')) {
                    if (stack.length > 1) stack.pop();
                } else {
                    const template = document.createElement('div');
                    template.innerHTML = node.value;
                    const tag = template.firstChild;
                    if (tag) {
                        tag.style.display = 'contents';
                        stack[stack.length - 1].appendChild(tag);
                        stack.push(tag);
                    }
                }
            } else if (node.type === 'glue' && node.width !== 0) {
                let adjustedWidth = node.width || 0;
                if (ratio > 0) {
                    adjustedWidth += (node.stretch || 0) * ratio;
                } else if (ratio < 0) {
                    adjustedWidth += (node.shrink || 0) * ratio;
                }
                currentLeft += adjustedWidth;
            } else if (node.type === 'penalty' && node.penalty === 100 && line.hyphenated && j === line.nodes.length - 1 && lastChild) {
                lastChild.innerHTML = `${lastChild.innerHTML}-`;
            }
        }
    }

    measureNaturalLineWidth(nodes, startPosition, endPosition) {
        let width = 0;
        for (let j = startPosition; j <= endPosition; j++) {
            const node = nodes[j];
            if (!node) continue;
            if (node.type === 'box' || node.type === 'glue') {
                width += node.width || 0;
            } else if (node.type === 'penalty' && node.penalty === 100 && j === endPosition) {
                width += node.width || 0;
            }
        }
        return width;
    }

    /**
     * Paragraph positions are already computed from browser DOM measurements.
     * Keep this hook for callers that still invoke it, but do not reflow the
     * prototype layout after rendering.
     * @param {HTMLElement} paragraph - Rendered paragraph element
     */
    adjustJustification(paragraph) {
        return paragraph;
    }
    
}

// Create the singleton instance
const LayoutRenderer = new LayoutRendererModule();

// Export the module
export { LayoutRenderer };

// Register with the module registry
if (window.moduleRegistry) {
    window.moduleRegistry.register(LayoutRenderer);
}

// Keep a reference in window for loader system
window.LayoutRenderer = LayoutRenderer;