<?php
session_start();
header('Content-Type: application/json');

if (!isset($_SESSION['admin_id'])) {
    echo json_encode(['success' => false, 'message' => 'Unauthorized access']);
    exit;
}

require_once '../config/config.php';
require_once '../config/db.php';

$action = $_POST['action'] ?? '';
$current_user_id = $_SESSION['admin_id'];

// ==================== ADD TEMPLATE ====================
if ($action === 'add_template') {
    
    $template_name = mysqli_real_escape_string($con, $_POST['template_name']);
    $template_code = mysqli_real_escape_string($con, $_POST['template_code']);
    $category = mysqli_real_escape_string($con, $_POST['category']);
    $is_active = mysqli_real_escape_string($con, $_POST['is_active']);
    $color_scheme = mysqli_real_escape_string($con, $_POST['color_scheme']);
    
    $introduction = mysqli_real_escape_string($con, $_POST['introduction']);
    $company_overview = mysqli_real_escape_string($con, $_POST['company_overview']);
    $services_offered = mysqli_real_escape_string($con, $_POST['services_offered']);
    $methodology = mysqli_real_escape_string($con, $_POST['methodology']);
    $timeline_structure = mysqli_real_escape_string($con, $_POST['timeline_structure']);
    $pricing_structure = mysqli_real_escape_string($con, $_POST['pricing_structure']);
    $terms_conditions = mysqli_real_escape_string($con, $_POST['terms_conditions']);
    $conclusion = mysqli_real_escape_string($con, $_POST['conclusion']);
    $footer_text = mysqli_real_escape_string($con, $_POST['footer_text'] ?? '');
    
    // Check if template code exists
    $check_code = mysqli_query($con, "SELECT template_id FROM tbl_proposal_templates WHERE template_code = '$template_code'");
    if (mysqli_num_rows($check_code) > 0) {
        echo json_encode(['success' => false, 'message' => 'Template code already exists']);
        exit;
    }
    
    $query = "INSERT INTO tbl_proposal_templates (
                template_name, template_code, category, is_active, color_scheme,
                introduction, company_overview, services_offered, methodology,
                timeline_structure, pricing_structure, terms_conditions, conclusion,
                footer_text, created_by
              ) VALUES (
                '$template_name', '$template_code', '$category', '$is_active', '$color_scheme',
                '$introduction', '$company_overview', '$services_offered', '$methodology',
                '$timeline_structure', '$pricing_structure', '$terms_conditions', '$conclusion',
                '$footer_text', $current_user_id
              )";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Template created successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== EDIT TEMPLATE ====================
elseif ($action === 'edit_template') {
    
    $template_id = intval($_POST['template_id']);
    $template_name = mysqli_real_escape_string($con, $_POST['template_name']);
    $template_code = mysqli_real_escape_string($con, $_POST['template_code']);
    $category = mysqli_real_escape_string($con, $_POST['category']);
    $is_active = mysqli_real_escape_string($con, $_POST['is_active']);
    $color_scheme = mysqli_real_escape_string($con, $_POST['color_scheme']);
    
    $introduction = mysqli_real_escape_string($con, $_POST['introduction']);
    $company_overview = mysqli_real_escape_string($con, $_POST['company_overview']);
    $services_offered = mysqli_real_escape_string($con, $_POST['services_offered']);
    $methodology = mysqli_real_escape_string($con, $_POST['methodology']);
    $timeline_structure = mysqli_real_escape_string($con, $_POST['timeline_structure']);
    $pricing_structure = mysqli_real_escape_string($con, $_POST['pricing_structure']);
    $terms_conditions = mysqli_real_escape_string($con, $_POST['terms_conditions']);
    $conclusion = mysqli_real_escape_string($con, $_POST['conclusion']);
    $footer_text = mysqli_real_escape_string($con, $_POST['footer_text'] ?? '');
    
    // Check if template code exists for other templates
    $check_code = mysqli_query($con, "SELECT template_id FROM tbl_proposal_templates WHERE template_code = '$template_code' AND template_id != $template_id");
    if (mysqli_num_rows($check_code) > 0) {
        echo json_encode(['success' => false, 'message' => 'Template code already exists']);
        exit;
    }
    
    $query = "UPDATE tbl_proposal_templates SET 
                template_name = '$template_name',
                template_code = '$template_code',
                category = '$category',
                is_active = '$is_active',
                color_scheme = '$color_scheme',
                introduction = '$introduction',
                company_overview = '$company_overview',
                services_offered = '$services_offered',
                methodology = '$methodology',
                timeline_structure = '$timeline_structure',
                pricing_structure = '$pricing_structure',
                terms_conditions = '$terms_conditions',
                conclusion = '$conclusion',
                footer_text = '$footer_text'
              WHERE template_id = $template_id";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Template updated successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== DELETE TEMPLATE ====================
elseif ($action === 'delete_template') {
    
    $template_id = intval($_POST['template_id']);
    
    // Check if template is default
    $check_default = mysqli_query($con, "SELECT is_default FROM tbl_proposal_templates WHERE template_id = $template_id");
    $template_data = mysqli_fetch_assoc($check_default);
    
    if ($template_data && $template_data['is_default'] === 'Yes') {
        echo json_encode(['success' => false, 'message' => 'Cannot delete default template']);
        exit;
    }
    
    // Check if template is used in any quotations
    $check_usage = mysqli_query($con, "SELECT COUNT(*) as count FROM tbl_quotations WHERE template_id = $template_id");
    $usage_data = mysqli_fetch_assoc($check_usage);
    
    if ($usage_data['count'] > 0) {
        echo json_encode(['success' => false, 'message' => 'Cannot delete template - it is used in ' . $usage_data['count'] . ' quotation(s)']);
        exit;
    }
    
    $query = "DELETE FROM tbl_proposal_templates WHERE template_id = $template_id";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Template deleted successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== DUPLICATE TEMPLATE ====================
elseif ($action === 'duplicate_template') {
    
    $template_id = intval($_POST['template_id']);
    
    // Get original template
    $get_template = mysqli_query($con, "SELECT * FROM tbl_proposal_templates WHERE template_id = $template_id");
    $template = mysqli_fetch_assoc($get_template);
    
    if (!$template) {
        echo json_encode(['success' => false, 'message' => 'Template not found']);
        exit;
    }
    
    // Generate new template code
    $new_code = $template['template_code'] . '-COPY';
    $counter = 1;
    while (mysqli_num_rows(mysqli_query($con, "SELECT template_id FROM tbl_proposal_templates WHERE template_code = '$new_code'")) > 0) {
        $new_code = $template['template_code'] . '-COPY' . $counter;
        $counter++;
    }
    
    $new_name = $template['template_name'] . ' (Copy)';
    
    $query = "INSERT INTO tbl_proposal_templates (
                template_name, template_code, category, is_active, color_scheme,
                introduction, company_overview, services_offered, methodology,
                timeline_structure, pricing_structure, terms_conditions, conclusion,
                footer_text, is_default, created_by
              ) VALUES (
                '$new_name', '$new_code', '{$template['category']}', '{$template['is_active']}', '{$template['color_scheme']}',
                '{$template['introduction']}', '{$template['company_overview']}', '{$template['services_offered']}', '{$template['methodology']}',
                '{$template['timeline_structure']}', '{$template['pricing_structure']}', '{$template['terms_conditions']}', '{$template['conclusion']}',
                '{$template['footer_text']}', 'No', $current_user_id
              )";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Template duplicated successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== SET DEFAULT TEMPLATE ====================
elseif ($action === 'set_default_template') {
    
    $template_id = intval($_POST['template_id']);
    
    // First, remove default from all templates
    mysqli_query($con, "UPDATE tbl_proposal_templates SET is_default = 'No'");
    
    // Then set the selected template as default
    $query = "UPDATE tbl_proposal_templates SET is_default = 'Yes' WHERE template_id = $template_id";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Default template updated successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== GET DEFAULT TEMPLATE ====================
// Updated: Removed customer default_template_id references since that field was removed
elseif ($action === 'get_customer_template') {
    
    // Simply get the system default template
    $default_query = "SELECT * FROM tbl_proposal_templates WHERE is_default = 'Yes' LIMIT 1";
    $default_result = mysqli_query($con, $default_query);
    $default_template = mysqli_fetch_assoc($default_result);
    
    if ($default_template) {
        echo json_encode(['success' => true, 'template' => $default_template]);
    } else {
        // If no default template set, get the first active template
        $fallback_query = "SELECT * FROM tbl_proposal_templates WHERE is_active = 'Yes' ORDER BY created_at DESC LIMIT 1";
        $fallback_result = mysqli_query($con, $fallback_query);
        $fallback_template = mysqli_fetch_assoc($fallback_result);
        
        if ($fallback_template) {
            echo json_encode(['success' => true, 'template' => $fallback_template]);
        } else {
            echo json_encode(['success' => false, 'message' => 'No template found']);
        }
    }
}

// ==================== ADD QUOTATION ====================
elseif ($action === 'add_quotation') {
    
    $customer_id = intval($_POST['customer_id']);
    $template_id = intval($_POST['template_id']);
    $quotation_title = mysqli_real_escape_string($con, $_POST['quotation_title']);
    $quotation_date = mysqli_real_escape_string($con, $_POST['quotation_date']);
    $valid_until = mysqli_real_escape_string($con, $_POST['valid_until']);
    
    $quotation_items = mysqli_real_escape_string($con, $_POST['quotation_items'] ?? '[]');
    $total_amount = floatval($_POST['total_amount']);
    $discount_percentage = floatval($_POST['discount_percentage'] ?? 0);
    $discount_amount = floatval($_POST['discount_amount'] ?? 0);
    $final_amount = floatval($_POST['final_amount']);
    
    $internal_notes = mysqli_real_escape_string($con, $_POST['internal_notes'] ?? '');
    $status = mysqli_real_escape_string($con, $_POST['status'] ?? 'Draft');
    
    // Generate quotation code
    $last_code_query = mysqli_query($con, "SELECT quotation_code FROM tbl_quotations ORDER BY quotation_id DESC LIMIT 1");
    if (mysqli_num_rows($last_code_query) > 0) {
        $last_row = mysqli_fetch_assoc($last_code_query);
        $last_number = intval(str_replace('QUOT-', '', $last_row['quotation_code']));
        $new_number = $last_number + 1;
    } else {
        $new_number = 1;
    }
    $quotation_code = 'QUOT-' . str_pad($new_number, 4, '0', STR_PAD_LEFT);
    
    $query = "INSERT INTO tbl_quotations (
                quotation_code, customer_id, template_id, quotation_title, quotation_date, valid_until,
                quotation_items, total_amount, discount_percentage, discount_amount, final_amount,
                internal_notes, status, created_by
              ) VALUES (
                '$quotation_code', $customer_id, $template_id, '$quotation_title', '$quotation_date', '$valid_until',
                '$quotation_items', $total_amount, $discount_percentage, $discount_amount, $final_amount,
                '$internal_notes', '$status', $current_user_id
              )";
    
    if (mysqli_query($con, $query)) {
        echo json_encode([
            'success' => true, 
            'message' => 'Quotation created successfully!',
            'quotation_code' => $quotation_code
        ]);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== EDIT QUOTATION ====================
elseif ($action === 'edit_quotation') {
    
    $quotation_id = intval($_POST['quotation_id']);
    $customer_id = intval($_POST['customer_id']);
    $template_id = intval($_POST['template_id']);
    $quotation_title = mysqli_real_escape_string($con, $_POST['quotation_title']);
    $quotation_date = mysqli_real_escape_string($con, $_POST['quotation_date']);
    $valid_until = mysqli_real_escape_string($con, $_POST['valid_until']);
    
    $quotation_items = mysqli_real_escape_string($con, $_POST['quotation_items'] ?? '[]');
    $total_amount = floatval($_POST['total_amount']);
    $discount_percentage = floatval($_POST['discount_percentage'] ?? 0);
    $discount_amount = floatval($_POST['discount_amount'] ?? 0);
    $final_amount = floatval($_POST['final_amount']);
    
    $internal_notes = mysqli_real_escape_string($con, $_POST['internal_notes'] ?? '');
    $status = mysqli_real_escape_string($con, $_POST['status'] ?? 'Draft');
    
    $query = "UPDATE tbl_quotations SET 
                customer_id = $customer_id,
                template_id = $template_id,
                quotation_title = '$quotation_title',
                quotation_date = '$quotation_date',
                valid_until = '$valid_until',
                quotation_items = '$quotation_items',
                total_amount = $total_amount,
                discount_percentage = $discount_percentage,
                discount_amount = $discount_amount,
                final_amount = $final_amount,
                internal_notes = '$internal_notes',
                status = '$status'
              WHERE quotation_id = $quotation_id";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Quotation updated successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== DELETE QUOTATION ====================
elseif ($action === 'delete_quotation') {
    
    $quotation_id = intval($_POST['quotation_id']);
    
    $query = "DELETE FROM tbl_quotations WHERE quotation_id = $quotation_id";
    
    if (mysqli_query($con, $query)) {
        echo json_encode(['success' => true, 'message' => 'Quotation deleted successfully!']);
    } else {
        echo json_encode(['success' => false, 'message' => 'Database error: ' . mysqli_error($con)]);
    }
}

// ==================== GET QUOTATION (FOR EDITING) ====================
elseif ($action === 'get_quotation') {
    
    $quotation_id = intval($_POST['quotation_id']);
    
    $query = "SELECT * FROM tbl_quotations WHERE quotation_id = $quotation_id";
    $result = mysqli_query($con, $query);
    
    if ($result && mysqli_num_rows($result) > 0) {
        $quotation = mysqli_fetch_assoc($result);
        echo json_encode(['success' => true, 'quotation' => $quotation]);
    } else {
        echo json_encode(['success' => false, 'message' => 'Quotation not found']);
    }
}

else {
    echo json_encode(['success' => false, 'message' => 'Invalid action']);
}

mysqli_close($con);
?>