<?php
require_once __DIR__ . '/../helpers.php';
runAuth();

/**
 * Get Menu for Builder
 * Returns categories and items in structured format for the menu builder UI
 */

/**
 * Recursively build nested options tree from flat rows.
 */
function buildOptionsTree(array $allOptions, int $parentId): array {
    $result = [];
    foreach ($allOptions as $opt) {
        if ((int) $opt['ParentItemID'] !== $parentId) continue;

        $children = buildOptionsTree($allOptions, (int) $opt['ItemID']);
        $result[] = [
            'id'                => 'opt_' . $opt['ItemID'],
            'dbId'              => (int) $opt['ItemID'],
            'name'              => $opt['Name'],
            'price'             => $opt['Price'],
            'isDefault'         => (int) $opt['IsDefault'] === 1,
            'sortOrder'         => (int) $opt['SortOrder'],
            'requiresSelection' => (int) ($opt['RequiresSelection'] ?? 0) === 1,
            'maxSelections'     => (int) ($opt['MaxSelections'] ?? 0),
            'options'           => $children,
        ];
    }
    usort($result, fn($a, $b) => $a['sortOrder'] - $b['sortOrder']);
    return $result;
}

$data = readJsonBody();
$businessID = (int) ($data['BusinessID'] ?? 0);

if ($businessID === 0) {
    jsonResponse(['OK' => false, 'ERROR' => 'missing_business_id', 'MESSAGE' => 'BusinessID is required']);
}

$menuID = (int) ($data['MenuID'] ?? 0);

try {
    // Get business default menu and timezone
    $defaultMenuID = 0;
    $businessTimezone = 'America/Los_Angeles';
    try {
        $qBiz = queryOne("SELECT DefaultMenuID, Timezone FROM Businesses WHERE ID = ?", [$businessID]);
        if ($qBiz) {
            if (!empty($qBiz['DefaultMenuID'])) $defaultMenuID = (int) $qBiz['DefaultMenuID'];
            if (!empty($qBiz['Timezone'])) $businessTimezone = $qBiz['Timezone'];
        }
    } catch (Exception $e) {}

    // Get all menus for this business
    $allMenus = [];
    try {
        $qMenus = queryTimed("
            SELECT ID, Name, Description, DaysActive, StartTime, EndTime, SortOrder
            FROM Menus
            WHERE BusinessID = ? AND IsActive = 1
            ORDER BY SortOrder, Name
        ", [$businessID]);

        foreach ($qMenus as $m) {
            $allMenus[] = [
                'MenuID'          => (int) $m['ID'],
                'MenuName'        => $m['Name'],
                'MenuDescription' => $m['Description'] ?? '',
                'MenuDaysActive'  => (int) $m['DaysActive'],
                'MenuStartTime'   => !empty($m['StartTime']) ? (new DateTime($m['StartTime']))->format('H:i') : '',
                'MenuEndTime'     => !empty($m['EndTime']) ? (new DateTime($m['EndTime']))->format('H:i') : '',
                'SortOrder'       => (int) $m['SortOrder'],
            ];
        }

        // Auto-select menu based on current time when no specific menu requested
        if ($menuID === 0 && count($qMenus) > 1) {
            $currentTime = substr(getTimeInZone($businessTimezone), 0, 5); // "HH:mm"
            $currentDay = getDayInZone($businessTimezone); // 1=Sun, 2=Mon, ... 7=Sat
            $dayBit = pow(2, $currentDay - 1);
            $activeMenuIds = [];

            foreach ($qMenus as $m) {
                if (((int) $m['DaysActive'] & $dayBit) === 0) continue;

                $hasStart = !empty($m['StartTime']);
                $hasEnd = !empty($m['EndTime']);
                if ($hasStart && $hasEnd) {
                    $startT = (new DateTime($m['StartTime']))->format('H:i');
                    $endT = (new DateTime($m['EndTime']))->format('H:i');
                    if ($currentTime >= $startT && $currentTime <= $endT) {
                        $activeMenuIds[] = (int) $m['ID'];
                    }
                } else {
                    $activeMenuIds[] = (int) $m['ID'];
                }
            }

            if (count($activeMenuIds) === 1) {
                $menuID = $activeMenuIds[0];
            } elseif (count($activeMenuIds) > 1 && $defaultMenuID > 0 && in_array($defaultMenuID, $activeMenuIds)) {
                $menuID = $defaultMenuID;
            }
        }
    } catch (Exception $e) {
        // Menus table might not exist yet
    }

    // Check if Categories table has data
    $hasCategoriesData = false;
    try {
        $qCatCheck = queryOne("SELECT 1 as x FROM Categories WHERE BusinessID = ? LIMIT 1", [$businessID]);
        $hasCategoriesData = $qCatCheck !== null;
    } catch (Exception $e) {}

    if ($hasCategoriesData) {
        // Use Categories table
        $catParams = [$businessID];
        $menuFilter = '';
        if ($menuID > 0) {
            $menuFilter = ' AND MenuID = ?';
            $catParams[] = $menuID;
        }

        $qCatRows = queryTimed("
            SELECT ID, Name, ParentCategoryID, SortOrder, MenuID
            FROM Categories
            WHERE BusinessID = ? $menuFilter
            ORDER BY SortOrder, Name
        ", $catParams);

        $qItemRows = queryTimed("
            SELECT
                i.ID, i.CategoryID as CategoryItemID, i.Name, i.Description,
                i.Price, i.SortOrder, i.IsActive
            FROM Items i
            WHERE i.BusinessID = ?
              AND i.IsActive = 1
              AND i.CategoryID > 0
            ORDER BY i.SortOrder, i.Name
        ", [$businessID]);

        $qDirectModifiers = queryTimed("
            SELECT
                m.ID as ItemID, m.ParentItemID, m.Name, m.Price,
                m.IsCheckedByDefault as IsDefault, m.SortOrder,
                m.RequiresChildSelection as RequiresSelection,
                m.MaxNumSelectionReq as MaxSelections
            FROM Items m
            WHERE m.BusinessID = ?
              AND m.IsActive = 1
              AND m.ParentItemID > 0
              AND (m.CategoryID = 0 OR m.CategoryID IS NULL)
            ORDER BY m.SortOrder, m.Name
        ", [$businessID]);

    } else {
        // Unified schema: Categories are Items at ParentID=0
        $qCatRows = queryTimed("
            SELECT DISTINCT
                p.ID, p.Name, 0 AS ParentCategoryID, p.SortOrder, 0 AS MenuID
            FROM Items p
            INNER JOIN Items c ON c.ParentItemID = p.ID
            WHERE p.BusinessID = ?
              AND p.ParentItemID = 0
              AND p.IsActive = 1
              AND NOT EXISTS (
                SELECT 1 FROM lt_ItemID_TemplateItemID tl WHERE tl.TemplateItemID = p.ID
              )
            ORDER BY p.SortOrder, p.Name
        ", [$businessID]);

        $qItemRows = queryTimed("
            SELECT
                i.ID, i.ParentItemID as CategoryItemID, i.Name, i.Description,
                i.Price, i.SortOrder, i.IsActive
            FROM Items i
            INNER JOIN Items cat ON cat.ID = i.ParentItemID
            WHERE i.BusinessID = ?
              AND i.IsActive = 1
              AND cat.ParentItemID = 0
              AND NOT EXISTS (
                SELECT 1 FROM lt_ItemID_TemplateItemID tl WHERE tl.TemplateItemID = cat.ID
              )
            ORDER BY i.SortOrder, i.Name
        ", [$businessID]);

        $qDirectModifiers = queryTimed("
            SELECT
                m.ID as ItemID, m.ParentItemID, m.Name, m.Price,
                m.IsCheckedByDefault as IsDefault, m.SortOrder,
                m.RequiresChildSelection as RequiresSelection,
                m.MaxNumSelectionReq as MaxSelections
            FROM Items m
            WHERE m.BusinessID = ?
              AND m.IsActive = 1
              AND m.ParentItemID > 0
            ORDER BY m.SortOrder, m.Name
        ", [$businessID]);
    }

    // Collect menu item IDs
    $menuItemIds = array_column($qItemRows, 'ID');

    // Get template links for this business's menu items
    $qTemplateLinkRows = [];
    if (count($menuItemIds) > 0) {
        $placeholders = implode(',', array_fill(0, count($menuItemIds), '?'));
        $qTemplateLinkRows = queryTimed("
            SELECT tl.ItemID as ParentItemID, tl.TemplateItemID, tl.SortOrder
            FROM lt_ItemID_TemplateItemID tl
            WHERE tl.ItemID IN ($placeholders)
            ORDER BY tl.ItemID, tl.SortOrder
        ", $menuItemIds);
    }

    // Get templates for this business
    $qTemplateRows = queryTimed("
        SELECT DISTINCT
            t.ID as ItemID, t.Name, t.Price,
            t.IsCheckedByDefault as IsDefault, t.SortOrder,
            t.RequiresChildSelection as RequiresSelection,
            t.MaxNumSelectionReq as MaxSelections
        FROM Items t
        WHERE t.BusinessID = ?
          AND (t.CategoryID = 0 OR t.CategoryID IS NULL)
          AND t.ParentItemID = 0
          AND t.IsActive = 1
        ORDER BY t.SortOrder, t.Name
    ", [$businessID]);

    $templateIds = array_column($qTemplateRows, 'ItemID');

    // Get template children
    $qTemplateChildRows = [];
    if (count($templateIds) > 0) {
        $placeholders = implode(',', array_fill(0, count($templateIds), '?'));
        $qTemplateChildRows = queryTimed("
            SELECT
                c.ID as ItemID, c.ParentItemID, c.Name, c.Price,
                c.IsCheckedByDefault as IsDefault, c.SortOrder,
                c.RequiresChildSelection as RequiresSelection,
                c.MaxNumSelectionReq as MaxSelections
            FROM Items c
            WHERE c.ParentItemID IN ($placeholders) AND c.IsActive = 1
            ORDER BY c.SortOrder, c.Name
        ", $templateIds);
    }

    // Build templates lookup with options
    $templatesById = [];
    foreach ($qTemplateRows as $t) {
        $tid = (int) $t['ItemID'];
        $options = buildOptionsTree($qTemplateChildRows, $tid);
        $templatesById[$tid] = [
            'id'                => 'mod_' . $tid,
            'dbId'              => $tid,
            'name'              => $t['Name'],
            'price'             => $t['Price'],
            'isDefault'         => (int) $t['IsDefault'] === 1,
            'sortOrder'         => (int) $t['SortOrder'],
            'isTemplate'        => true,
            'requiresSelection' => (int) ($t['RequiresSelection'] ?? 0) === 1,
            'maxSelections'     => (int) ($t['MaxSelections'] ?? 0),
            'options'           => $options,
        ];
    }

    // Build template links lookup by parent ItemID
    $templateLinksByItem = [];
    foreach ($qTemplateLinkRows as $link) {
        $parentID = (int) $link['ParentItemID'];
        $templateID = (int) $link['TemplateItemID'];

        if (isset($templatesById[$templateID])) {
            $tmpl = $templatesById[$templateID]; // copy
            $tmpl['sortOrder'] = (int) $link['SortOrder'];
            $templateLinksByItem[$parentID][] = $tmpl;
        }
    }

    // Build direct modifiers by item
    $directModsByItem = [];
    foreach ($menuItemIds as $itemId) {
        $options = buildOptionsTree($qDirectModifiers, (int) $itemId);
        if (count($options) > 0) {
            $directModsByItem[(int) $itemId] = $options;
        }
    }

    // Build items lookup by CategoryID
    $itemsByCategory = [];
    $uploadsDir = luceeWebroot() . '/uploads/items';
    foreach ($qItemRows as $item) {
        $catID = (int) $item['CategoryItemID'];
        $itemID = (int) $item['ID'];

        // Get template-linked modifiers
        $itemModifiers = isset($templateLinksByItem[$itemID]) ? $templateLinksByItem[$itemID] : [];

        // Add direct modifiers
        if (isset($directModsByItem[$itemID])) {
            $itemModifiers = array_merge($itemModifiers, $directModsByItem[$itemID]);
        }

        // Sort modifiers by sortOrder
        usort($itemModifiers, fn($a, $b) => $a['sortOrder'] - $b['sortOrder']);

        // Check for existing item photo
        $itemImageUrl = null;
        foreach (['jpg', 'jpeg', 'png', 'gif', 'webp'] as $ext) {
            if (file_exists("$uploadsDir/{$itemID}.{$ext}")) {
                $itemImageUrl = "/uploads/items/{$itemID}.{$ext}";
                break;
            }
        }

        $itemsByCategory[$catID][] = [
            'id'          => 'item_' . $itemID,
            'dbId'        => $itemID,
            'name'        => $item['Name'],
            'description' => $item['Description'] ?? '',
            'price'       => $item['Price'],
            'imageUrl'    => $itemImageUrl,
            'photoTaskId' => null,
            'modifiers'   => $itemModifiers,
            'sortOrder'   => (int) $item['SortOrder'],
        ];
    }

    // Build categories array
    $categories = [];
    $catIndex = 0;
    foreach ($qCatRows as $cat) {
        $catID = (int) $cat['ID'];
        $catItems = $itemsByCategory[$catID] ?? [];

        $catStruct = [
            'id'          => 'cat_' . $catID,
            'dbId'        => $catID,
            'name'        => $cat['Name'],
            'description' => '',
            'sortOrder'   => $catIndex,
            'items'       => $catItems,
        ];

        if ($hasCategoriesData) {
            $catStruct['menuId'] = (int) ($cat['MenuID'] ?? 0);
            $catStruct['parentCategoryId'] = (int) ($cat['ParentCategoryID'] ?? 0);
            $catStruct['parentCategoryDbId'] = (int) ($cat['ParentCategoryID'] ?? 0);
        }

        $categories[] = $catStruct;
        $catIndex++;
    }

    // Build template library
    $templateLibrary = array_values($templatesById);

    // Get brand colors
    $brandColor = '';
    $brandColorLight = '';
    try {
        $qBrand = queryOne("SELECT BrandColor, BrandColorLight FROM Businesses WHERE ID = ?", [$businessID]);
        if ($qBrand) {
            if (!empty($qBrand['BrandColor'])) {
                $brandColor = $qBrand['BrandColor'][0] === '#' ? $qBrand['BrandColor'] : '#' . $qBrand['BrandColor'];
            }
            if (!empty($qBrand['BrandColorLight'])) {
                $brandColorLight = $qBrand['BrandColorLight'][0] === '#' ? $qBrand['BrandColorLight'] : '#' . $qBrand['BrandColorLight'];
            }
        }
    } catch (Exception $e) {}

    $totalItems = 0;
    foreach ($categories as $cat) {
        $totalItems += count($cat['items']);
    }

    jsonResponse([
        'OK'              => true,
        'MENU'            => ['categories' => $categories],
        'MENUS'           => $allMenus,
        'SELECTED_MENU_ID' => $menuID,
        'DEFAULT_MENU_ID'  => $defaultMenuID,
        'TEMPLATES'       => $templateLibrary,
        'BRANDCOLOR'      => $brandColor,
        'BRANDCOLORLIGHT' => $brandColorLight,
        'CATEGORY_COUNT'  => count($categories),
        'TEMPLATE_COUNT'  => count($templateLibrary),
        'MENU_COUNT'      => count($allMenus),
        'SCHEMA'          => $hasCategoriesData ? 'legacy' : 'unified',
        'ITEM_COUNT'      => $totalItems,
    ]);

} catch (Exception $e) {
    jsonResponse(['OK' => false, 'ERROR' => 'server_error', 'MESSAGE' => $e->getMessage(), 'DETAIL' => '']);
}