/**
 * Workflow Handlers - Simplified 3-Step Workflow
 */

import { appState, setCroppedEmbryos, setCurrentEmbryoIndex, getEmbryoRemark, setEmbryoRemark } from '../state.js';
import { runClassification, evaluateEmbryo } from '../models/inference.js';
import { detectEmbryos, isYOLOAvailable } from '../models/yoloDetection.js';
import { showToast } from '../ui/toast.js';
import { displayClassificationStatus, displayFinalResults } from '../ui/results.js';
import { displayCroppedEmbryo } from '../ui/imageDisplay.js';
import { enableNextButton, disableNextButton, markStepCompleted } from '../ui/stepper.js';
import { showCropEditor, hideCropEditor } from '../ui/cropEditor.js';
import { showConfirmModal } from '../ui/modal.js';
import { initializeInlineDetection } from '../ui/inlineDetection.js';

/**
 * Classify if image contains embryo (auto-triggered on upload)
 */
export async function classifyImage(imageData) {
    const statusDiv = document.getElementById('classificationStatus');
    
    try {
        if (statusDiv) {
            statusDiv.innerHTML = `
                <div style="text-align: center;">
                    <div class="spinner" style="width: 30px; height: 30px; margin: 10px auto;"></div>
                    <p>Analyzing image...</p>
                </div>
            `;
        }
        
        showToast('Classifying image...', 'info');
        
        const result = await runClassification(imageData);
        displayClassificationStatus(result);
        
        // Enable next button if classification successful and it's an embryo
        if (result && result.label === 'yes') {
            enableNextButton(1);
            showToast('Image classified successfully - Embryo detected!', 'success');
        } else if (result && result.label === 'no') {
            disableNextButton(1); // Ensure button is disabled for non-embryo images
            showToast('No embryo detected in the image', 'warning');
            if (statusDiv) {
                statusDiv.innerHTML = `
                    <p style="color: var(--warning-color);"><strong>No embryo detected</strong></p>
                    <p>Please upload an image containing an embryo to continue.</p>
                `;
            }
        }
    } catch (error) {
        console.error('Classification error:', error);
        showToast(`Classification failed: ${error.message}`, 'error');
        if (statusDiv) {
            statusDiv.innerHTML = `
                <p style="color: var(--error-color);"><strong>Classification failed</strong></p>
                <p>${error.message}</p>
            `;
        }
    }
}

/**
 * Show embryo image in Step 2 and then trigger detection
 */
export async function showEmbryoImageAndDetect() {
    // First, display the original embryo image
    const step2Content = document.getElementById('step2');
    if (!step2Content || !step2Content.classList.contains('active')) {
        console.error('Step 2 not active yet, waiting...');
        await new Promise(resolve => setTimeout(resolve, 200));
    }
    
    const canvas = document.getElementById('detectionCanvas');
    
    // Show the original embryo image on the canvas first
    if (canvas && appState.currentImage) {
        try {
            const ctx = canvas.getContext('2d');
            const { loadImage } = await import('../utils/imageUtils.js');
            const imageElement = await loadImage(appState.currentImage);
            
            // Set canvas size to match image
            canvas.width = imageElement.width;
            canvas.height = imageElement.height;
            
            // Calculate scale factor for display
            const container = canvas.parentElement;
            if (container) {
                const maxWidth = container.clientWidth - 40;
                const maxHeight = 600;
                
                const scaleFactor = Math.min(
                    maxWidth / imageElement.width,
                    maxHeight / imageElement.height,
                    1
                );
                
                canvas.style.width = `${imageElement.width * scaleFactor}px`;
                canvas.style.height = `${imageElement.height * scaleFactor}px`;
            }
            
            // Draw the original image
            ctx.drawImage(imageElement, 0, 0);
        } catch (error) {
            console.error('Error displaying embryo image:', error);
        }
    }
    
    // Wait a moment to let the UI update and show the image
    await new Promise(resolve => setTimeout(resolve, 500));
    
    // Now trigger detection
    await detectAndDisplayEmbryos();
}

/**
 * Detect and display embryos (triggered on Step 2)
 */
export async function detectAndDisplayEmbryos() {
    if (!isYOLOAvailable()) {
        showToast('Detection model not available', 'error');
        return;
    }
    
    // Verify Step 2 is visible
    const step2Content = document.getElementById('step2');
    if (!step2Content || !step2Content.classList.contains('active')) {
        console.error('Step 2 not active yet, waiting...');
        // Wait and retry
        await new Promise(resolve => setTimeout(resolve, 200));
    }
    
    try {
        showToast('Detecting embryos...', 'info');
        
        const detections = await detectEmbryos(appState.currentImage);
        
        if (detections.length === 0) {
            showToast('No embryos detected - You can add manually', 'info');
            
            // Initialize with empty array to allow manual addition
            setCroppedEmbryos([]);
            await displayDetectedEmbryosForSelection([]);
            return;
        }
        
        setCroppedEmbryos(detections);
        await displayDetectedEmbryosForSelection(detections);
        
        showToast(`Detected ${detections.length} embryo(s) - Click to select`, 'success');
    } catch (error) {
        console.error('Detection error:', error);
        showToast(`Detection failed: ${error.message}`, 'error');
    }
}

/**
 * Display detected embryos for selection (Step 2) - Using inline detection view
 */
async function displayDetectedEmbryosForSelection(detections) {
    // Wait a bit for DOM to be ready (Step 2 to be visible)
    await new Promise(resolve => setTimeout(resolve, 100));
    
    // Initialize the inline detection canvas with all embryos (or empty array)
    await initializeInlineDetection(appState.currentImage, detections);
    
    // Enable next button only if there are embryos (either detected or manually added)
    if (detections.length > 0) {
        enableNextButton(2);
    }
}

/**
 * Select embryo for analysis (updates selection in Step 2)
 */
function selectEmbryoForAnalysis(index) {
    setCurrentEmbryoIndex(index);
    displayCroppedEmbryo(index, appState.croppedEmbryos[index], appState.croppedEmbryos.length);
    
    // Update active thumbnail
    document.querySelectorAll('.embryo-thumbnail-wrapper').forEach((wrapper, i) => {
        const thumbnail = wrapper.querySelector('.embryo-thumbnail');
        if (thumbnail) {
            thumbnail.classList.toggle('active', i === index);
        }
    });
    
    const selectionInfo = document.getElementById('selectionInfo');
    if (selectionInfo) {
        selectionInfo.innerHTML = `
            <p><strong>Embryo ${index + 1} of ${appState.croppedEmbryos.length} selected</strong></p>
            <p>Click 'Analyze Selected Embryo' to continue</p>
        `;
    }
    
    // Show crop editor for selected embryo
    showCropEditor(index);
    
    // Update navigation buttons
    updateNavigationButtons();
}

/**
 * Navigate between embryos in Step 2
 */
export function navigateEmbryo(direction) {
    const newIndex = appState.currentEmbryoIndex + direction;
    if (newIndex >= 0 && newIndex < appState.croppedEmbryos.length) {
        selectEmbryoForAnalysis(newIndex);
    }
    
    // Update navigation button states
    updateNavigationButtons();
}

/**
 * Update navigation button states
 */
function updateNavigationButtons() {
    const prevBtn = document.getElementById('prevEmbryoBtn');
    const nextBtn = document.getElementById('nextEmbryoBtn');
    
    if (prevBtn) {
        prevBtn.disabled = appState.currentEmbryoIndex === 0;
    }
    
    if (nextBtn) {
        nextBtn.disabled = appState.currentEmbryoIndex >= appState.croppedEmbryos.length - 1;
    }
}

/**
 * Discard an embryo from the analysis
 */
async function discardEmbryo(index) {
    if (appState.croppedEmbryos.length <= 1) {
        showToast('Cannot discard the last embryo', 'warning');
        return;
    }
    
    const confirmed = await showConfirmModal(
        `Are you sure you want to discard Embryo ${index + 1}?`,
        'Discard Embryo'
    );
    
    if (!confirmed) {
        return;
    }
    
    // Remove embryo from array
    appState.croppedEmbryos.splice(index, 1);
    
    // Adjust current index if necessary
    if (appState.currentEmbryoIndex >= appState.croppedEmbryos.length) {
        appState.currentEmbryoIndex = Math.max(0, appState.croppedEmbryos.length - 1);
    }
    
    // Update the display
    redisplayEmbryos();
    
    showToast('Embryo discarded', 'success');
}

/**
 * Redisplay all embryos after changes (e.g., discard)
 */
function redisplayEmbryos() {
    const thumbnailContainer = document.getElementById('embryoThumbnails');
    if (!thumbnailContainer) return;
    
    thumbnailContainer.innerHTML = '';
    
    appState.croppedEmbryos.forEach((detection, index) => {
        const thumbnailWrapper = document.createElement('div');
        thumbnailWrapper.className = 'embryo-thumbnail-wrapper';
        thumbnailWrapper.setAttribute('data-embryo-index', index);
        
        const thumbnail = document.createElement('div');
        thumbnail.className = 'embryo-thumbnail';
        if (index === appState.currentEmbryoIndex) thumbnail.classList.add('active');
        
        const img = document.createElement('img');
        img.src = detection.imageData;
        img.alt = `Embryo ${index + 1}`;
        
        // Add discard button with closure to capture current index
        const discardBtn = document.createElement('button');
        discardBtn.className = 'discard-embryo-btn';
        discardBtn.innerHTML = '×';
        discardBtn.title = 'Discard this embryo';
        discardBtn.addEventListener('click', ((currentIndex) => {
            return (e) => {
                e.stopPropagation();
                discardEmbryo(currentIndex);
            };
        })(index));
        
        thumbnail.appendChild(img);
        thumbnail.appendChild(discardBtn);
        
        // Add click handler with closure to capture current index
        thumbnail.addEventListener('click', ((currentIndex) => {
            return () => selectEmbryoForAnalysis(currentIndex);
        })(index));
        
        thumbnailWrapper.appendChild(thumbnail);
        thumbnailContainer.appendChild(thumbnailWrapper);
    });
    
    // Select current embryo (index has been adjusted in discardEmbryo)
    if (appState.croppedEmbryos.length > 0) {
        selectEmbryoForAnalysis(appState.currentEmbryoIndex);
    }
}


/**
 * Evaluate all embryos in background (triggered when entering Step 3)
 */
export async function evaluateAllEmbryos() {
    const resultsDiv = document.getElementById('finalResults');
    
    try {
        showToast('Processing all embryos...', 'info');
        
        if (resultsDiv) {
            resultsDiv.innerHTML = `
                <div style="text-align: center;">
                    <div class="spinner" style="width: 40px; height: 40px; margin: 20px auto;"></div>
                    <p>Analyzing ${appState.croppedEmbryos.length} embryo(s)...</p>
                    <p style="font-size: 0.9em; color: var(--text-secondary);">This may take a few moments</p>
                </div>
            `;
        }
        
        // Process all embryos in parallel
        const evaluationPromises = appState.croppedEmbryos.map(async (embryo, index) => {
            try {
                const result = await evaluateEmbryo(embryo.imageData);
                return {
                    index,
                    embryo,
                    result,
                    success: true
                };
            } catch (error) {
                console.error(`Error evaluating embryo ${index + 1}:`, error);
                return {
                    index,
                    embryo,
                    result: null,
                    success: false,
                    error: error.message
                };
            }
        });
        
        const results = await Promise.all(evaluationPromises);
        
        // Store results in appState
        appState.embryoResults = results;
        
        // Display all embryos with their results
        displayAllEmbryosWithResults(results);
        
        // Mark step as completed
        markStepCompleted(3);
        
        const successCount = results.filter(r => r.success).length;
        if (successCount === results.length) {
            showToast(`Successfully processed all ${results.length} embryos`, 'success');
        } else {
            showToast(`Processed ${successCount} of ${results.length} embryos (${results.length - successCount} failed)`, 'warning');
        }
    } catch (error) {
        console.error('Evaluation error:', error);
        showToast(`Evaluation failed: ${error.message}`, 'error');
        if (resultsDiv) {
            resultsDiv.innerHTML = `
                <p style="color: var(--error-color);"><strong>Evaluation failed</strong></p>
                <p>${error.message}</p>
            `;
        }
    }
}

/**
 * Display all embryos with clickable thumbnails in Step 3
 */
function displayAllEmbryosWithResults(results) {
    const resultsDiv = document.getElementById('finalResults');
    if (!resultsDiv) return;
    
    resultsDiv.innerHTML = `
        <div class="all-embryos-results">
            <h3>All Embryos Results</h3>
            <p style="margin-bottom: 20px; color: var(--text-secondary);">
                Click on any embryo to view its detailed results
            </p>
            <div class="embryo-results-grid" id="embryoResultsGrid"></div>
            <div class="selected-embryo-details" id="selectedEmbryoDetails" style="margin-top: 30px;"></div>
        </div>
    `;
    
    const grid = document.getElementById('embryoResultsGrid');
    
    results.forEach((resultData, index) => {
        const card = document.createElement('div');
        card.className = 'embryo-result-card';
        card.setAttribute('data-embryo-index', index);
        
        const hasRemark = getEmbryoRemark(index).trim().length > 0;
        
        if (resultData.success) {
            const grade = resultData.result.grade || 'Unknown';
            const quality = resultData.result.quality || 'Unknown';
            
            card.innerHTML = `
                <div class="embryo-result-thumbnail">
                    <img src="${resultData.embryo.imageData}" alt="Embryo ${index + 1}">
                    <div class="embryo-result-badge">${grade}</div>
                </div>
                <div class="embryo-result-info">
                    <strong>Embryo ${index + 1}</strong>
                    <span class="quality-indicator quality-${quality.toLowerCase()}">${quality}</span>
                </div>
            `;
        } else {
            card.innerHTML = `
                <div class="embryo-result-thumbnail">
                    <img src="${resultData.embryo.imageData}" alt="Embryo ${index + 1}">
                    <div class="embryo-result-badge error">Error</div>
                </div>
                <div class="embryo-result-info">
                    <strong>Embryo ${index + 1}</strong>
                    <span class="quality-indicator quality-error">Failed</span>
                </div>
            `;
        }
        
        card.addEventListener('click', () => showEmbryoDetailedResult(index, resultData));
        
        grid.appendChild(card);
    });
    
    // Auto-select first embryo
    if (results.length > 0) {
        showEmbryoDetailedResult(0, results[0]);
    }
}

/**
 * Show detailed result for a specific embryo
 */
function showEmbryoDetailedResult(index, resultData) {
    const detailsDiv = document.getElementById('selectedEmbryoDetails');
    if (!detailsDiv) return;
    
    // Update active card
    document.querySelectorAll('.embryo-result-card').forEach((card, i) => {
        card.classList.toggle('active', i === index);
    });
    
    const currentRemark = getEmbryoRemark(index);
    
    if (!resultData.success) {
        detailsDiv.innerHTML = `
            <div class="detailed-result-container">
                <h3>Embryo ${index + 1} - Processing Failed</h3>
                <div class="error-message">
                    <p>${resultData.error || 'Unknown error occurred'}</p>
                </div>
                <div class="remarks-section">
                    <label for="embryoRemark${index}">Remarks:</label>
                    <textarea 
                        id="embryoRemark${index}" 
                        class="remarks-textarea" 
                        placeholder="Add your observations, notes, or comments about this embryo..."
                        data-embryo-index="${index}"
                    >${currentRemark}</textarea>
                </div>
            </div>
        `;
        
        // Add event listener to save remarks when changed
        const remarkTextarea = document.getElementById(`embryoRemark${index}`);
        if (remarkTextarea) {
            remarkTextarea.addEventListener('input', (e) => {
                setEmbryoRemark(index, e.target.value);
            });
        }
        return;
    }
    
    const result = resultData.result;
    
    detailsDiv.innerHTML = `
        <div class="detailed-result-container">
            <div class="result-header">
                <h3>Embryo ${index + 1} - Detailed Results</h3>
            </div>
            <div class="result-content">
                <div class="result-image-section">
                    <img src="${resultData.embryo.imageData}" alt="Embryo ${index + 1}" class="result-embryo-image">
                </div>
                <div class="result-details-section">
                    <div class="result-row">
                        <span class="result-label">Quality Assessment:</span>
                        <span class="result-value quality-${result.quality?.toLowerCase() || 'unknown'}">${result.quality || 'Unknown'}</span>
                    </div>
                    <div class="result-row">
                        <span class="result-label">Predicted Grade:</span>
                        <span class="result-value grade-value">${result.grade || 'Unknown'}</span>
                    </div>
                    <div class="result-row">
                        <span class="result-label">Actual Grade:</span>
                        <div class="actual-grade-selectors">
                            <select id="actualGradeNum${index}" class="grade-select" data-embryo-index="${index}">
                                <option value="">-</option>
                                <option value="1">1</option>
                                <option value="2">2</option>
                                <option value="3">3</option>
                                <option value="4">4</option>
                                <option value="5">5</option>
                                <option value="6">6</option>
                            </select>
                            <select id="actualGradeLetter1${index}" class="grade-select" data-embryo-index="${index}">
                                <option value="">-</option>
                                <option value="A">A</option>
                                <option value="B">B</option>
                                <option value="C">C</option>
                            </select>
                            <select id="actualGradeLetter2${index}" class="grade-select" data-embryo-index="${index}">
                                <option value="">-</option>
                                <option value="A">A</option>
                                <option value="B">B</option>
                                <option value="C">C</option>
                            </select>
                            <span class="grade-preview" id="gradePreview${index}"></span>
                        </div>
                    </div>
                    ${result.confidence ? `
                    <div class="result-row">
                        <span class="result-label">Confidence:</span>
                        <span class="result-value">${(result.confidence * 100).toFixed(1)}%</span>
                    </div>
                    ` : ''}
                    ${result.poorGoodConfidence ? `
                    <div class="result-row">
                        <span class="result-label">Quality Confidence:</span>
                        <span class="result-value">${(result.poorGoodConfidence * 100).toFixed(1)}%</span>
                    </div>
                    ` : ''}
                    <div class="remarks-section">
                        <label for="embryoRemark${index}">Remarks:</label>
                        <textarea 
                            id="embryoRemark${index}" 
                            class="remarks-textarea" 
                            placeholder="Add your observations, notes, or comments about this embryo..."
                            data-embryo-index="${index}"
                        >${currentRemark}</textarea>
                    </div>
                </div>
            </div>
        </div>
    `;
    
    // Add event listener to save remarks when changed
    const remarkTextarea = document.getElementById(`embryoRemark${index}`);
    if (remarkTextarea) {
        remarkTextarea.addEventListener('input', (e) => {
            setEmbryoRemark(index, e.target.value);
        });
    }
    
    // Parse existing actualGrade if available
    const existingGrade = resultData.embryo.actualGrade || '';
    if (existingGrade) {
        // Parse grade like "3AA" into number and letters
        const match = existingGrade.match(/^(\d)([A-C])([A-C])$/);
        if (match) {
            const numSelect = document.getElementById(`actualGradeNum${index}`);
            const letter1Select = document.getElementById(`actualGradeLetter1${index}`);
            const letter2Select = document.getElementById(`actualGradeLetter2${index}`);
            
            if (numSelect) numSelect.value = match[1];
            if (letter1Select) letter1Select.value = match[2];
            if (letter2Select) letter2Select.value = match[3];
        }
    }
    
    // Function to update the combined grade
    const updateActualGrade = () => {
        const numSelect = document.getElementById(`actualGradeNum${index}`);
        const letter1Select = document.getElementById(`actualGradeLetter1${index}`);
        const letter2Select = document.getElementById(`actualGradeLetter2${index}`);
        const gradePreview = document.getElementById(`gradePreview${index}`);
        
        const num = numSelect?.value || '';
        const letter1 = letter1Select?.value || '';
        const letter2 = letter2Select?.value || '';
        
        const combinedGrade = num + letter1 + letter2;
        
        // Update preview
        if (gradePreview) {
            gradePreview.textContent = combinedGrade || '-';
        }
        
        // Save to embryo object
        const embryo = appState.croppedEmbryos[index];
        if (embryo) {
            embryo.actualGrade = combinedGrade;
        }
    };
    
    // Add event listeners to all three selects
    const numSelect = document.getElementById(`actualGradeNum${index}`);
    const letter1Select = document.getElementById(`actualGradeLetter1${index}`);
    const letter2Select = document.getElementById(`actualGradeLetter2${index}`);
    
    if (numSelect) {
        numSelect.addEventListener('change', updateActualGrade);
    }
    if (letter1Select) {
        letter1Select.addEventListener('change', updateActualGrade);
    }
    if (letter2Select) {
        letter2Select.addEventListener('change', updateActualGrade);
    }
    
    // Initial update
    updateActualGrade();
}

/**
 * Legacy function - kept for compatibility but redirects to new function
 */
export async function evaluateSelectedEmbryo() {
    return evaluateAllEmbryos();
}