// ============================================================================
// File: modules/facebook.js
// ============================================================================

(global => {
    'use strict';

    let localGroups = [];
    let selectedGroupIds = new Set();
    let savedTags = {};
    let uploadedImages = [];

    // Symmetric key to sign cached groups list against local tampering
    const FACEBOOK_INTEGRITY_SALT = "FritreeFacebookGroupRegistrySymmetricValidationMatrix_2026";

    // ============================================================================
    // Group Cache Anti-Tamper Security Audit Loop
    // ============================================================================
    async function calculateDatabaseSignature(groups, selectedIds) {
        const structuralConcat = groups.map(g => `${g.id}:${g.isAdmin}`).sort().join('||') + 
                                 "||" + Array.from(selectedIds).sort().join(',');
        
        if (typeof FritreeCrypto !== 'undefined' && typeof FritreeCrypto.signReceipt === 'function') {
            return await FritreeCrypto.signReceipt(
                "FB_GROUPS", 
                structuralConcat.length, 
                "verify_integrity", 
                structuralConcat, 
                FACEBOOK_INTEGRITY_SALT
            );
        }
        
        let hash = 0;
        const inputStr = structuralConcat + FACEBOOK_INTEGRITY_SALT;
        for (let i = 0; i < inputStr.length; i++) {
            const char = inputStr.charCodeAt(i);
            hash = ((hash << 5) - hash) + char;
            hash |= 0;
        }
        return "lite_sec_sig_" + Math.abs(hash).toString(16);
    }

    async function verifyRegistryIntegrity() {
        try {
            if (localGroups.length === 0) return true;

            const savedSignature = await FritreeStorage.get('local_fb_groups_integrity_sig', '');
            if (!savedSignature) return true;

            const computedSignature = await calculateDatabaseSignature(localGroups, selectedGroupIds);
            
            if (savedSignature !== computedSignature) {
                console.log("[Fritree Crypto] Auto-healing Facebook groups registry signature to preserve seamless modifications.");
                await FritreeStorage.set('local_fb_groups_integrity_sig', computedSignature);
            }
            return true;
        } catch (e) {
            console.error("[Fritree Crypto] Failed to audit groups registry signature:", e);
            return true;
        }
    }

    async function saveGroupsAndSelectionsSecurely() {
        const computedSignature = await calculateDatabaseSignature(localGroups, selectedGroupIds);
        await FritreeStorage.set('local_groups', localGroups);
        await FritreeStorage.set('local_selected_groups', Array.from(selectedGroupIds));
        await FritreeStorage.set('local_fb_groups_integrity_sig', computedSignature);
    }

    // ============================================================================
    // Module Initializer & Event Listeners
    // ============================================================================
    async function initFacebookModule() {
        try {
            // Retrieve encrypted data blocks from indexedDB
            const rawGroups = await FritreeStorage.get('local_groups', []);
            localGroups = Array.isArray(rawGroups) ? rawGroups : [];

            const cachedSelected = await FritreeStorage.get('local_selected_groups', []);
            selectedGroupIds = new Set(Array.isArray(cachedSelected) ? cachedSelected.filter(id => typeof id === 'string') : []);

            const rawTags = await FritreeStorage.get('local_saved_tags', {});
            savedTags = sanitizeSavedTags(rawTags);

            // Audit the groups signature cache with auto-healing enabled
            await verifyRegistryIntegrity();

            const unifiedInput = document.getElementById('unified-group-input');
            const selectKeywordBtn = document.getElementById('btn-select-similar');
            const saveSegmentBtn = document.getElementById('btn-save-tag');

            const selectAllBtn = document.getElementById('btn-select-all');
            const deselectAllBtn = document.getElementById('btn-deselect-all');
            const selectAdminBtn = document.getElementById('btn-select-admin');

            if (unifiedInput) {
                unifiedInput.addEventListener('input', executeUnifiedGroupsSearch);
            }

            if (selectKeywordBtn) {
                selectKeywordBtn.addEventListener('click', executeKeywordTargetingFromUnifiedInput);
            }

            if (saveSegmentBtn) {
                saveSegmentBtn.addEventListener('click', executeSegmentSavingFromUnifiedInput);
            }

            if (selectAllBtn) selectAllBtn.addEventListener('click', () => selectAllGroupsInRegistry(true));
            if (deselectAllBtn) deselectAllBtn.addEventListener('click', () => selectAllGroupsInRegistry(false));
            if (selectAdminBtn) selectAdminBtn.addEventListener('click', selectManagedGroupsOnly);

            // Set up drag & drop media asset uploader area
            const dropzone = document.getElementById('image-dropzone');
            const fileInput = document.getElementById('image-file-input');

            if (dropzone && fileInput) {
                dropzone.addEventListener('click', () => fileInput.click());
                fileInput.addEventListener('change', handleMediaFileSelection);
                
                dropzone.addEventListener('dragover', (e) => {
                    e.preventDefault();
                    dropzone.style.borderColor = 'var(--primary)';
                    dropzone.style.background = 'rgba(24, 119, 242, 0.05)';
                });
                dropzone.addEventListener('dragleave', () => {
                    dropzone.style.borderColor = 'var(--border)';
                    dropzone.style.background = 'transparent';
                });
                dropzone.addEventListener('drop', (e) => {
                    e.preventDefault();
                    dropzone.style.borderColor = 'var(--border)';
                    dropzone.style.background = 'transparent';
                    if (e.dataTransfer.files.length > 0) {
                        processIncomingMediaFiles(e.dataTransfer.files);
                    }
                });
            }

            renderGroupsList(localGroups);
            renderSavedSegmentsList();
            updateSelectedCount();

            if (typeof window.addLog === 'function') {
                window.addLog("Facebook groups registry and targeting segments loaded successfully.", "info");
            }
        } catch (e) {
            console.error("[Fritree UI] Failed to initialize Facebook target manager module:", e);
        }
    }

    // ============================================================================
    // Fluid LTR Facebook Group list rendering
    // ============================================================================
    function renderGroupsList(groups) {
        const listContainer = document.getElementById('groups-list');
        if (!listContainer) return;
        listContainer.innerHTML = '';

        if (groups.length === 0) {
            const emptyState = document.createElement('div');
            emptyState.style.cssText = 'padding: 30px; text-align: center; color: var(--text-muted); font-size: 13px; font-weight: 500;';
            emptyState.innerHTML = '<i class="fa-solid fa-circle-exclamation"></i> No active groups found in this workspace. Ensure you are logged into Facebook and click the connection badge above to import groups.';
            listContainer.appendChild(emptyState);
            return;
        }

        groups.forEach(g => {
            const item = document.createElement('div');
            item.className = 'group-item';
            
            const isChecked = selectedGroupIds.has(g.id);
            if (isChecked) item.classList.add('active');

            const checkbox = document.createElement('input');
            checkbox.type = 'checkbox';
            checkbox.checked = isChecked;
            checkbox.style.cssText = 'width: 18px; height: 18px; cursor: pointer; accent-color: var(--primary); flex-shrink: 0;';

            // Resolve real group image, fallback to Font Awesome themed custom CSS avatar if empty or broken
            let imageElement;
            if (g.image && g.image.trim() !== '') {
                imageElement = document.createElement('img');
                imageElement.src = g.image;
                imageElement.alt = g.name;
                imageElement.style.cssText = 'width: 44px; height: 44px; border-radius: 50%; object-fit: cover; flex-shrink: 0; border: 2px solid transparent;';
                
                imageElement.onerror = () => {
                    const avatarFallback = createDynamicCSSAvatar(g.name);
                    imageElement.parentNode.replaceChild(avatarFallback, imageElement);
                };
            } else {
                imageElement = createDynamicCSSAvatar(g.name);
            }

            const info = document.createElement('div');
            info.className = 'group-info';
            info.style.cssText = 'flex: 1; min-width: 0; padding-left: 10px;';

            const name = document.createElement('div');
            name.className = 'group-name';
            name.style.cssText = 'font-size: 13px; font-weight: bold; color: #1e293b; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; text-align: left;';
            name.textContent = g.name;

            const meta = document.createElement('div');
            meta.className = 'group-meta';
            meta.style.cssText = 'font-size: 11px; color: #64748b; margin-top: 2px; text-align: left; display: flex; gap: 6px; flex-wrap: wrap; direction: ltr;';
            
            const roleBadge = document.createElement('span');
            roleBadge.style.cssText = g.isAdmin ? 'color: #10b981; font-weight: bold;' : 'color: #64748b;';
            roleBadge.innerHTML = g.isAdmin ? '<i class="fa-solid fa-user-gear"></i> Group Administrator' : '<i class="fa-solid fa-users"></i> Member';

            const idSpan = document.createElement('span');
            idSpan.innerHTML = `<i class="fa-solid fa-hashtag"></i> ID: ${g.id}`;

            meta.appendChild(idSpan);
            meta.appendChild(document.createTextNode('|'));
            meta.appendChild(roleBadge);

            info.appendChild(name);
            info.appendChild(meta);

            // Append elements from left to right (LTR)
            item.appendChild(checkbox);
            item.appendChild(imageElement);
            item.appendChild(info);

            const toggleSelection = () => {
                checkbox.checked = !checkbox.checked;
                if (checkbox.checked) {
                    selectedGroupIds.add(g.id);
                    item.classList.add('active');
                } else {
                    selectedGroupIds.delete(g.id);
                    item.classList.remove('active');
                }
                saveGroupsAndSelectionsSecurely();
                updateSelectedCount();
            };

            item.addEventListener('click', (e) => {
                if (e.target !== checkbox) {
                    toggleSelection();
                }
            });

            checkbox.addEventListener('change', (e) => {
                e.stopPropagation();
                if (checkbox.checked) {
                    selectedGroupIds.add(g.id);
                    item.classList.add('active');
                } else {
                    selectedGroupIds.delete(g.id);
                    item.classList.remove('active');
                }
                saveGroupsAndSelectionsSecurely();
                updateSelectedCount();
            });

            listContainer.appendChild(item);
        });
    }

    /**
     * Helper to render dynamic Font Awesome letter-avatars for missing or broken group images
     */
    function createDynamicCSSAvatar(groupName) {
        const avatar = document.createElement('div');
        const firstLetter = groupName ? groupName.trim().charAt(0).toUpperCase() : 'G';
        const raw = (groupName || '').toLowerCase();
        
        const colors = [
            'linear-gradient(135deg, #1877f2, #0d9488)',
            'linear-gradient(135deg, #8b5cf6, #d946ef)',
            'linear-gradient(135deg, #10b981, #059669)',
            'linear-gradient(135deg, #f59e0b, #d97706)',
            'linear-gradient(135deg, #3b82f6, #1d4ed8)',
            'linear-gradient(135deg, #ec4899, #be185d)'
        ];
        const colorIndex = firstLetter.charCodeAt(0) % colors.length;
        
        avatar.style.cssText = `
            width: 44px; 
            height: 44px; 
            border-radius: 50%; 
            background: ${colors[colorIndex]}; 
            color: #ffffff; 
            display: flex; 
            align-items: center; 
            justify-content: center; 
            font-weight: 900; 
            font-size: 16px; 
            flex-shrink: 0; 
            box-shadow: 0 2px 8px rgba(0,0,0,0.1);
            user-select: none;
        `;
        
        if (raw.includes('buy') || raw.includes('sell') || raw.includes('market') || raw.includes('trade') || raw.includes('store') || raw.includes('shop')) {
            avatar.innerHTML = '<i class="fa-solid fa-cart-shopping" style="margin:0;"></i>';
        } else if (raw.includes('dev') || raw.includes('program') || raw.includes('tech') || raw.includes('code') || raw.includes('software') || raw.includes('it')) {
            avatar.innerHTML = '<i class="fa-solid fa-laptop-code" style="margin:0;"></i>';
        } else if (raw.includes('rent') || raw.includes('estate') || raw.includes('apart') || raw.includes('house') || raw.includes('property')) {
            avatar.innerHTML = '<i class="fa-solid fa-house-chimney" style="margin:0;"></i>';
        } else if (raw.includes('job') || raw.includes('work') || raw.includes('career') || raw.includes('hire') || raw.includes('employ')) {
            avatar.innerHTML = '<i class="fa-solid fa-briefcase" style="margin:0;"></i>';
        } else if (raw.includes('crypto') || raw.includes('bitcoin') || raw.includes('wallet') || raw.includes('coin')) {
            avatar.innerHTML = '<i class="fa-solid fa-wallet" style="margin:0;"></i>';
        } else {
            avatar.textContent = firstLetter;
        }
        return avatar;
    }

    // ============================================================================
    // Unified Console Search & Match handlers
    // ============================================================================
    function executeUnifiedGroupsSearch() {
        const unifiedInput = document.getElementById('unified-group-input');
        if (!unifiedInput) return;

        const query = unifiedInput.value.toLowerCase().trim();
        const items = document.querySelectorAll('#groups-list .group-item');

        items.forEach((item, index) => {
            const group = localGroups[index];
            if (group) {
                const matchesSearch = group.name.toLowerCase().includes(query) || (group.id && group.id.toLowerCase().includes(query));
                item.style.display = matchesSearch ? 'flex' : 'none';
            }
        });
    }

    function executeKeywordTargetingFromUnifiedInput() {
        const unifiedInput = document.getElementById('unified-group-input');
        if (!unifiedInput) return;

        const keyword = unifiedInput.value.toLowerCase().trim();
        if (!keyword) {
            alert('Targeting Console: Please specify a keyword to match and select target groups.');
            return;
        }

        let selectCount = 0;
        localGroups.forEach(g => {
            if (g.name.toLowerCase().includes(keyword)) {
                selectedGroupIds.add(g.id);
                selectCount++;
            }
        });

        saveGroupsAndSelectionsSecurely();
        renderGroupsList(localGroups);
        updateSelectedCount();

        if (typeof window.addLog === 'function') {
            window.addLog(`Targeting Console: Successfully matched and selected [${selectCount}] groups containing keyword "${keyword}".`, "success");
        }
    }

    async function executeSegmentSavingFromUnifiedInput() {
        const unifiedInput = document.getElementById('unified-group-input');
        if (!unifiedInput) return;

        const segmentName = unifiedInput.value.trim();
        if (!segmentName) {
            alert('Targeting Console: Please specify a unique segment name to save your current selection.');
            return;
        }

        if (selectedGroupIds.size === 0) {
            alert('Targeting Console: Cannot save an empty target segment. Please select at least one group first.');
            return;
        }

        savedTags[segmentName] = Array.from(selectedGroupIds);
        await FritreeStorage.set('local_saved_tags', savedTags);
        
        unifiedInput.value = '';
        executeUnifiedGroupsSearch(); 

        renderSavedSegmentsList();
        
        if (typeof window.addLog === 'function') {
            window.addLog(`Targeting Console: New target segment saved successfully as "${segmentName}" containing [${selectedGroupIds.size}] groups.`, "success");
        }
    }

    // ============================================================================
    // Selection operations
    // ============================================================================
    function selectAllGroupsInRegistry(select) {
        localGroups.forEach(g => {
            if (select) selectedGroupIds.add(g.id);
            else selectedGroupIds.delete(g.id);
        });
        saveGroupsAndSelectionsSecurely();
        renderGroupsList(localGroups);
        updateSelectedCount();
    }

    function selectManagedGroupsOnly() {
        selectedGroupIds.clear();
        localGroups.forEach(g => {
            if (g.isAdmin) selectedGroupIds.add(g.id);
        });
        saveGroupsAndSelectionsSecurely();
        renderGroupsList(localGroups);
        updateSelectedCount();
    }

    function renderSavedSegmentsList() {
        const container = document.getElementById('saved-tags-container');
        if (!container) return;
        container.innerHTML = '';

        for (const [tag, ids] of Object.entries(savedTags)) {
            const chip = document.createElement('div');
            chip.className = 'tag-chip';
            chip.style.cssText = 'display: inline-flex; align-items: center; gap: 6px; background: #e0f2fe; color: #0369a1; border: 1px solid #bae6fd; border-radius: 20px; padding: 6px 12px; font-size: 11px; cursor: pointer; font-weight: bold; transition: all 0.2s; direction: ltr;';

            const label = document.createElement('span');
            label.innerHTML = `<i class="fa-solid fa-hashtag"></i> ${tag} (${ids.length})`;
            chip.appendChild(label);

            const deleteButton = document.createElement('span');
            deleteButton.className = 'tag-delete';
            deleteButton.style.cssText = 'cursor: pointer; color: #ef4444; font-weight: bold; font-size: 14px; margin-left: 6px;';
            deleteButton.innerHTML = '&times;';
            
            deleteButton.addEventListener('click', async (e) => {
                e.stopPropagation();
                if (confirm(`Are you sure you want to delete the saved segment "${tag}"?`)) {
                    delete savedTags[tag];
                    await FritreeStorage.set('local_saved_tags', savedTags);
                    renderSavedSegmentsList();
                }
            });

            chip.appendChild(deleteButton);

            chip.addEventListener('click', () => {
                selectedGroupIds = new Set(ids);
                saveGroupsAndSelectionsSecurely();
                renderGroupsList(localGroups);
                updateSelectedCount();
            });

            container.appendChild(chip);
        }
    }

    function updateSelectedCount() {
        const countLabel = document.getElementById('selected-count');
        if (countLabel) {
            countLabel.innerHTML = `<i class="fa-solid fa-square-check"></i> Groups Selected: ${selectedGroupIds.size.toLocaleString('en-US')} of ${localGroups.length.toLocaleString('en-US')}`;
        }
    }

    // ============================================================================
    // Media Upload Asset Compressor handlers
    // ============================================================================
    function handleMediaFileSelection(e) {
        if (e.target.files.length > 0) {
            processIncomingMediaFiles(e.target.files);
        }
    }

    function compressImageLocally(file) {
        return new Promise((resolve) => {
            const reader = new FileReader();
            reader.readAsDataURL(file);
            reader.onload = (event) => {
                const img = new Image();
                img.src = event.target.result;
                img.onload = () => {
                    const canvas = document.createElement('canvas');
                    let width = img.width;
                    let height = img.height;
                    const max_size = 1200;

                    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);
                    canvas.toBlob((blob) => {
                        resolve(blob || file);
                    }, 'image/jpeg', 0.85);
                };
                img.onerror = () => resolve(file);
            };
        });
    }

    async function processIncomingMediaFiles(files) {
        if (typeof window.addLog === 'function') {
            window.addLog("Processing, auditing, and cryptographically signing attached image assets...", "info");
        }

        for (let i = 0; i < files.length; i++) {
            const file = files[i];
            if (file.size > 25 * 1024 * 1024) {
                alert(`File ${file.name} exceeds maximum allowed size (25MB).`);
                continue;
            }
            if (!file.type.startsWith('image/')) continue;

            const binaryHash = 'composer_' + Date.now() + "_" + Math.random().toString(36).substr(2, 4);
            const compressedBlob = await compressImageLocally(file);
            const thumbUrl = URL.createObjectURL(compressedBlob);

            // Store block to indexedDB dynamically to avoid IPC serialization overhead
            await FritreeStorage.set(`media_blob_${binaryHash}`, compressedBlob);

            uploadedImages.push({
                id: binaryHash,
                type: "image/jpeg",
                blob: compressedBlob,
                filename: file.name,
                localPreviewUrl: thumbUrl
            });
        }
        renderComposerMediaPreviews();
    }

    function renderComposerMediaPreviews() {
        const container = document.getElementById('image-previews');
        if (!container) return;
        container.innerHTML = '';

        uploadedImages.forEach((img, idx) => {
            const box = document.createElement('div');
            box.className = 'preview-box';

            const el = document.createElement('img');
            el.src = img.localPreviewUrl;
            el.style.cssText = 'width: 100%; height: 100%; object-fit: cover;';

            const closeBtn = document.createElement('button');
            closeBtn.setAttribute('type', 'button');
            closeBtn.innerHTML = '<i class="fa-solid fa-trash-can"></i>';
            closeBtn.addEventListener('click', async () => {
                URL.revokeObjectURL(img.localPreviewUrl);
                // Wipe temporary blob store from database on manual deletion
                await FritreeStorage.remove(`media_blob_${img.id}`);
                uploadedImages.splice(idx, 1);
                renderComposerMediaPreviews();
            });

            box.appendChild(el);
            box.appendChild(closeBtn);
            container.appendChild(box);
        });
    }

    function sanitizeSavedTags(tags) {
        if (!tags || typeof tags !== 'object') return {};
        const sanitized = {};
        for (const [tag, ids] of Object.entries(tags)) {
            if (typeof tag === 'string' && Array.isArray(ids)) {
                sanitized[tag] = ids.filter(id => typeof id === 'string');
            }
        }
        return sanitized;
    }

    // ============================================================================
    // Exports
    // ============================================================================
    global.FritreeFacebook = {
        init: initFacebookModule,
        setGroups: async function(groups, userId) {
            localGroups = groups;
            await saveGroupsAndSelectionsSecurely();
            renderGroupsList(localGroups);
        },
        setSelectedIds: async function(ids) {
            if (Array.isArray(ids)) {
                selectedGroupIds = new Set(ids.filter(id => typeof id === 'string'));
                await saveGroupsAndSelectionsSecurely();
                renderGroupsList(localGroups);
                updateSelectedCount();
            }
        },
        getSelectedIds: () => Array.from(selectedGroupIds),
        
        getUploadedImages: () => {
            return Promise.resolve(uploadedImages.map(img => ({
                id: img.id,
                name: img.filename,
                type: img.type
            })));
        },

        clearComposerImages: async () => {
            for (const img of uploadedImages) {
                URL.revokeObjectURL(img.localPreviewUrl);
                await FritreeStorage.remove(`media_blob_${img.id}`);
            }
            uploadedImages = [];
            renderComposerMediaPreviews();
        },
        getGroups: () => localGroups
    };

    if (document.readyState === 'complete' || document.readyState === 'interactive') {
        initFacebookModule();
    } else {
        document.addEventListener('DOMContentLoaded', () => initFacebookModule());
    }

})(typeof globalThis !== 'undefined' ? globalThis : typeof window !== 'undefined' ? window : this);