/**
 * Stepper Navigation - Handles multi-step workflow
 */

import { showConfirmModal } from './modal.js';
import { saveGradingResults, prepareEmbryoData, isFirebaseReady } from '../utils/firebaseService.js';
import { appState } from '../state.js';
import { showToast } from './toast.js';

let currentStep = 1;
const totalSteps = 3;

/**
 * Initialize stepper navigation
 */
export function initializeStepper() {
    updateStepperUI();
    attachStepperEventListeners();
}

/**
 * Navigate to a specific step
 */
export function goToStep(stepNumber) {
    if (stepNumber < 1 || stepNumber > totalSteps) return;
    
    currentStep = stepNumber;
    updateStepperUI();
    scrollToTop();
}

/**
 * Go to next step
 */
export function nextStep() {
    if (currentStep < totalSteps) {
        currentStep++;
        updateStepperUI();
        scrollToTop();
    }
}

/**
 * Go to previous step
 */
export function prevStep() {
    if (currentStep > 1) {
        currentStep--;
        updateStepperUI();
        scrollToTop();
    }
}

/**
 * Mark a step as completed
 */
export function markStepCompleted(stepNumber) {
    const step = document.querySelector(`.step[data-step="${stepNumber}"]`);
    if (step) {
        step.classList.add('completed');
    }
    
    // Update step line
    const stepLines = document.querySelectorAll('.step-line');
    if (stepLines[stepNumber - 1]) {
        stepLines[stepNumber - 1].classList.add('completed');
    }
}

/**
 * Update stepper UI
 */
function updateStepperUI() {
    // Update step indicators
    document.querySelectorAll('.step').forEach((step, index) => {
        const stepNum = index + 1;
        step.classList.remove('active');
        
        if (stepNum === currentStep) {
            step.classList.add('active');
        }
    });
    
    // Update step content visibility
    document.querySelectorAll('.step-content').forEach((content, index) => {
        const stepNum = index + 1;
        content.classList.remove('active');
        
        if (stepNum === currentStep) {
            content.classList.add('active');
        }
    });
}

/**
 * Reset stepper to first step
 */
export function resetStepper() {
    currentStep = 1;
    
    // Remove completed status from all steps
    document.querySelectorAll('.step').forEach(step => {
        step.classList.remove('completed', 'active');
    });
    
    document.querySelectorAll('.step-line').forEach(line => {
        line.classList.remove('completed');
    });
    
    updateStepperUI();
}

/**
 * Get current step number
 */
export function getCurrentStep() {
    return currentStep;
}

/**
 * Scroll to top of page
 */
function scrollToTop() {
    window.scrollTo({ top: 0, behavior: 'smooth' });
}

/**
 * Attach event listeners for step navigation
 */
function attachStepperEventListeners() {
    // Step 1 navigation
    const nextStep1 = document.getElementById('nextStep1');
    if (nextStep1) {
        nextStep1.addEventListener('click', () => {
            markStepCompleted(1);
            goToStep(2);
            initializeStep2();
        });
    }

    const startOverBtn = document.getElementById('startOverBtn');
    if (startOverBtn) {
        startOverBtn.addEventListener('click', async () => {
            const confirmed = await showConfirmModal(
                'Are you sure you want to start over? All progress will be lost.',
                'Start Over'
            );
            
            if (confirmed) {
                resetStepper();
                resetWorkflow();
            }
        });
    }

    // Step 2 navigation
    const prevStep2 = document.getElementById('prevStep2');
    if (prevStep2) {
        prevStep2.addEventListener('click', () => goToStep(1));
    }

    const nextStep2 = document.getElementById('nextStep2');
    if (nextStep2) {
        nextStep2.addEventListener('click', () => {
            markStepCompleted(2);
            goToStep(3);
            initializeStep3();
        });
    }

    // Step 3 navigation
    const prevStep3 = document.getElementById('prevStep3');
    if (prevStep3) {
        prevStep3.addEventListener('click', () => goToStep(2));
    }

    const analyzeAnother = document.getElementById('analyzeAnother');
    if (analyzeAnother) {
        analyzeAnother.addEventListener('click', async () => {
            // Save results first, then reset
            await handleSaveAndReset();
        });
    }
}

/**
 * Initialize Step 2 - Show embryo image and prepare for detection
 */
function initializeStep2() {
    // Show the embryo image first, then trigger detection after UI is ready
    setTimeout(() => {
        import('./workflow.js').then(module => {
            module.showEmbryoImageAndDetect();
        });
    }, 150);
}

/**
 * Initialize Step 3 - Evaluate all embryos in background
 */
function initializeStep3() {
    // Trigger evaluation of all embryos in background
    import('./workflow.js').then(module => {
        module.evaluateAllEmbryos();
    });
}

/**
 * Reset workflow (to be called from workflow.js)
 */
export function resetWorkflow() {
    // Reset file input to allow re-uploading the same file
    const imageInput = document.getElementById('imageInput');
    if (imageInput) {
        imageInput.value = '';
    }
    
    // Clear images
    const mainImage = document.getElementById('mainImage');
    const mainImagePreview = document.getElementById('mainImagePreview');
    const croppedImage = document.getElementById('croppedImage');
    const cropCanvas = document.getElementById('cropCanvas');
    
    if (mainImage) {
        mainImage.style.display = 'none';
        mainImage.src = '';
    }
    
    if (croppedImage) {
        croppedImage.style.display = 'none';
        croppedImage.src = '';
    }
    
    if (cropCanvas) {
        cropCanvas.style.display = 'none';
    }
    
    if (mainImagePreview) {
        const placeholder = mainImagePreview.querySelector('.placeholder');
        if (placeholder) placeholder.style.display = 'flex';
    }
    
    // Reset buttons
    const nextStep1 = document.getElementById('nextStep1');
    if (nextStep1) nextStep1.disabled = true;
    
    const nextStep2 = document.getElementById('nextStep2');
    if (nextStep2) nextStep2.disabled = true;
    
    // Clear classification status
    const classificationStatus = document.getElementById('classificationStatus');
    if (classificationStatus) {
        classificationStatus.innerHTML = `
            <p>Upload an image to check if it contains an embryo.</p>
            <p>The system will automatically classify the image upon upload.</p>
        `;
    }
    
    // Clear results
    const finalResults = document.getElementById('finalResults');
    if (finalResults) finalResults.innerHTML = '<p>Processing all embryos...</p>';
    
    const finalPredictions = document.getElementById('finalPredictions');
    if (finalPredictions) finalPredictions.innerHTML = '';
    
    const selectionInfo = document.getElementById('selectionInfo');
    if (selectionInfo) {
        selectionInfo.innerHTML = '<p>Select an embryo to continue.</p>';
    }
    
    // Clear embryo thumbnails
    const embryoThumbnails = document.getElementById('embryoThumbnails');
    if (embryoThumbnails) {
        embryoThumbnails.innerHTML = '';
    }
    
    // Disable zoom controls
    const zoomIn = document.getElementById('zoomIn');
    const zoomOut = document.getElementById('zoomOut');
    const zoomReset = document.getElementById('zoomReset');
    if (zoomIn) zoomIn.disabled = true;
    if (zoomOut) zoomOut.disabled = true;
    if (zoomReset) zoomReset.disabled = true;
    
    // Hide crop editor
    const cropControls = document.getElementById('cropControls');
    const editCropBtn = document.getElementById('editCropBtn');
    if (cropControls) cropControls.style.display = 'none';
    if (editCropBtn) editCropBtn.style.display = 'none';
    
    // Reset appState
    import('../state.js').then(module => {
        module.appState.croppedEmbryos = [];
        module.appState.embryoResults = [];
        module.appState.embryoRemarks = {};  // Clear all remarks
        module.appState.currentEmbryoIndex = 0;
        module.appState.currentImage = null;
        module.appState.zoomLevel = 1;
        module.appState.finalResult = null;
    });
}

/**
 * Enable next button for a step
 */
export function enableNextButton(stepNumber) {
    const button = document.getElementById(`nextStep${stepNumber}`);
    if (button) {
        button.disabled = false;
    }
}

/**
 * Disable next button for a step
 */
export function disableNextButton(stepNumber) {
    const button = document.getElementById(`nextStep${stepNumber}`);
    if (button) {
        button.disabled = true;
    }
}

/**
 * Handle saving results to Firebase
 */
async function handleSaveResults() {
    if (!isFirebaseReady()) {
        console.warn('Firebase is not configured.');
        return false;
    }
    
    if (!appState.croppedEmbryos || appState.croppedEmbryos.length === 0) {
        console.warn('No embryos to save');
        return false;
    }
    
    try {
        // Prepare the data with results and remarks
        const embryoData = prepareEmbryoData(
            appState.croppedEmbryos, 
            appState.currentImage,
            appState.embryoResults,
            appState.embryoRemarks
        );
        
        // Save to Firebase silently
        const docId = await saveGradingResults(embryoData);
        
        // Log to console for debugging
        console.log('Results saved successfully! Document ID:', docId);
        return true;
    } catch (error) {
        console.error('Error saving results:', error);
        return false;
    }
}

/**
 * Handle saving results and then resetting for a new analysis
 */
async function handleSaveAndReset() {
    // Save silently in background
    await handleSaveResults();
    
    // Reset immediately
    resetStepper();
    resetWorkflow();
}