<?php

namespace App\Controllers\Dashboard;

use App\Controllers\BaseController;
use App\Libraries\AuditLogger;
use App\Models\ChartModel;
use App\Models\DashboardModel;
use App\Models\DashboardWidgetModel;
use App\Models\QueryVariableModel;

class DashboardController extends BaseController
{
    public function index()
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $dashboards = (new DashboardModel())->forWorkspace($workspaceId);

        return view('dashboard/index', [
            'title'       => 'Dashboards | Chart-Board',
            'dashboards'  => $dashboards,
        ]);
    }

    public function store()
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $userId = (int) $this->session->get('user_id');

        $rules = [
            'name'        => 'required|min_length[2]|max_length[200]',
            'description' => 'permit_empty|max_length[2000]',
        ];

        if (! $this->validate($rules)) {
            return redirect()->back()->withInput()->with('errors', $this->validator->getErrors());
        }

        $name = strip_tags((string) $this->request->getPost('name'));
        $desc = trim((string) $this->request->getPost('description')) ?: null;

        $model = new DashboardModel();
        $slug = $model->generateUniqueSlug($workspaceId, $name);

        $id = (int) $model->insert([
            'workspace_id'     => $workspaceId,
            'name'             => $name,
            'description'      => $desc,
            'slug'             => $slug,
            'layout_config'    => null,
            'filters_config'   => null,
            'refresh_interval' => 0,
            'theme'            => 'system',
            'is_public'        => 0,
            'public_token'     => null,
            'public_password'  => null,
            'public_expires_at'=> null,
            'is_pinned'        => 0,
            'created_by'       => $userId,
        ], true);

        AuditLogger::log(
            'dashboard.created',
            'dashboard',
            $id,
            null,
            ['name' => $name],
            $workspaceId,
            $userId
        );

        return redirect()->to('/dashboard/view/' . $id)->with('success', 'Dashboard created. Add widgets and arrange your layout.');
    }

    public function viewBoard(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $dashModel = new DashboardModel();
        $dashboard = $dashModel->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return redirect()->to('/dashboard')->with('error', 'Dashboard not found.');
        }

        $widgets = (new DashboardWidgetModel())->forDashboard($id);
        $charts = (new ChartModel())->forWorkspace($workspaceId);

        return view('dashboard/view', [
            'title'       => (string) $dashboard['name'] . ' | Chart-Board',
            'dashboard'   => $dashboard,
            'widgets'     => $widgets,
            'chartsList'  => $charts,
            'dashBoot'    => [
                'dashboardId'   => $id,
                'dashboardName' => (string) ($dashboard['name'] ?? 'dashboard'),
                'workspaceTheme'=> (string) ($dashboard['theme'] ?? 'system'),
                'refreshSec'   => max(0, (int) ($dashboard['refresh_interval'] ?? 0)),
                'widgets'       => $this->widgetsBootPayload($widgets),
                'charts'        => array_map(static fn (array $c) => [
                    'id'   => (int) $c['id'],
                    'name' => (string) $c['name'],
                    'type' => (string) ($c['chart_type'] ?? ''),
                ], $charts),
                'urls' => [
                    'chartData'   => rtrim(base_url(), '/') . '/chart/',
                    'chartEdit'   => rtrim(base_url(), '/') . '/chart/edit/',
                    'chartExportBase' => rtrim(base_url(), '/') . '/chart/',
                    'dashboardVariables' => rtrim(base_url(), '/') . '/dashboard/' . $id . '/variables',
                    'saveLayout'  => rtrim(base_url(), '/') . '/dashboard/' . $id . '/layout',
                    'addWidget'   => rtrim(base_url(), '/') . '/dashboard/' . $id . '/widget',
                    'delWidget'   => rtrim(base_url(), '/') . '/dashboard/widget/',
                    'updateWidget' => rtrim(base_url(), '/') . '/dashboard/widget/',
                    'savedQueryVars' => rtrim(base_url(), '/') . '/chart/saved-query/',
                ],
                'csrf' => [
                    'name' => csrf_token(),
                    'hash' => csrf_hash(),
                ],
            ],
        ]);
    }

    /**
     * @param list<array<string, mixed>> $widgets
     * @return list<array<string, mixed>>
     */
    private function widgetsBootPayload(array $widgets): array
    {
        $out = [];
        foreach ($widgets as $w) {
            $cfg = null;
            if (! empty($w['widget_config'])) {
                $d = json_decode((string) $w['widget_config'], true);
                $cfg = is_array($d) ? $d : null;
            }
            $out[] = [
                'id'             => (int) $w['id'],
                'chart_id'       => isset($w['chart_id']) ? (int) $w['chart_id'] : null,
                'widget_type'    => (string) ($w['widget_type'] ?? 'chart'),
                'title'          => $w['title'] !== null && $w['title'] !== '' ? (string) $w['title'] : null,
                'grid_x'         => (int) ($w['grid_x'] ?? 0),
                'grid_y'         => (int) ($w['grid_y'] ?? 0),
                'grid_w'         => (int) ($w['grid_w'] ?? 4),
                'grid_h'         => (int) ($w['grid_h'] ?? 3),
                'content'        => $w['content'] !== null ? (string) $w['content'] : null,
                'widget_config'  => $cfg,
                'chart_name'     => isset($w['chart_name']) ? (string) $w['chart_name'] : null,
                'chart_type'     => isset($w['chart_type']) ? (string) $w['chart_type'] : null,
                'saved_query_id' => isset($w['saved_query_id']) ? (int) $w['saved_query_id'] : null,
            ];
        }

        return $out;
    }

    public function settings(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $dashboard = (new DashboardModel())->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return redirect()->to('/dashboard')->with('error', 'Dashboard not found.');
        }

        return view('dashboard/settings', [
            'title'     => 'Dashboard settings | Chart-Board',
            'dashboard' => $dashboard,
        ]);
    }

    /**
     * Return merged query variable definitions used by dashboard chart widgets.
     */
    public function variables(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $dashboard = (new DashboardModel())->findForWorkspace($id, $workspaceId);
        if (! $dashboard) {
            return $this->response->setJSON(['success' => false, 'message' => 'Dashboard not found.'])->setStatusCode(404);
        }

        $widgets = (new DashboardWidgetModel())->forDashboard($id);
        $queryIds = [];
        foreach ($widgets as $w) {
            if (($w['widget_type'] ?? '') !== 'chart') {
                continue;
            }
            $qid = (int) ($w['saved_query_id'] ?? 0);
            if ($qid > 0) {
                $queryIds[$qid] = true;
            }
        }
        $queryIds = array_keys($queryIds);
        if ($queryIds === []) {
            return $this->response->setJSON(['success' => true, 'variables' => []]);
        }

        $rows = (new QueryVariableModel())
            ->whereIn('saved_query_id', $queryIds)
            ->where('workspace_id', $workspaceId)
            ->orderBy('saved_query_id', 'ASC')
            ->orderBy('sort_order', 'ASC')
            ->findAll();

        $merged = [];
        foreach ($rows as $row) {
            $name = (string) ($row['name'] ?? '');
            if ($name === '') {
                continue;
            }
            $options = [];
            $optsRaw = $row['options_json'] ?? null;
            if ($optsRaw !== null && $optsRaw !== '') {
                $decoded = json_decode((string) $optsRaw, true);
                if (is_array($decoded)) {
                    $options = $decoded;
                }
            }

            if (! isset($merged[$name])) {
                $merged[$name] = [
                    'name' => $name,
                    'label' => (string) ($row['label'] ?? $name),
                    'type' => (string) ($row['type'] ?? 'text'),
                    'default_value' => (string) ($row['default_value'] ?? ''),
                    'is_required' => ! empty($row['is_required']),
                    'options' => $options,
                ];
                continue;
            }

            $merged[$name]['is_required'] = $merged[$name]['is_required'] || ! empty($row['is_required']);
            if ($merged[$name]['default_value'] === '' && (string) ($row['default_value'] ?? '') !== '') {
                $merged[$name]['default_value'] = (string) $row['default_value'];
            }
            if (($merged[$name]['label'] ?? '') === '' && (string) ($row['label'] ?? '') !== '') {
                $merged[$name]['label'] = (string) $row['label'];
            }
            if (($merged[$name]['type'] ?? 'text') === 'text' && (string) ($row['type'] ?? 'text') !== 'text') {
                $merged[$name]['type'] = (string) $row['type'];
            }
            if (is_array($options) && $options !== []) {
                $existing = is_array($merged[$name]['options']) ? $merged[$name]['options'] : [];
                foreach ($options as $opt) {
                    if (! in_array($opt, $existing, true)) {
                        $existing[] = $opt;
                    }
                }
                $merged[$name]['options'] = $existing;
            }
        }

        return $this->response->setJSON([
            'success' => true,
            'variables' => array_values($merged),
        ]);
    }

    public function updateSettings(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $model = new DashboardModel();
        $dashboard = $model->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return redirect()->to('/dashboard')->with('error', 'Dashboard not found.');
        }

        $rules = [
            'name'              => 'required|min_length[2]|max_length[200]',
            'description'       => 'permit_empty|max_length[2000]',
            'theme'             => 'required|in_list[light,dark,system]',
            'refresh_interval'  => 'permit_empty|integer',
        ];

        if (! $this->validate($rules)) {
            return redirect()->back()->withInput()->with('errors', $this->validator->getErrors());
        }

        $oldSnap = [
            'name'             => $dashboard['name'] ?? null,
            'theme'            => $dashboard['theme'] ?? null,
            'refresh_interval' => $dashboard['refresh_interval'] ?? null,
        ];
        $model->update($id, [
            'name'             => strip_tags((string) $this->request->getPost('name')),
            'description'      => trim((string) $this->request->getPost('description')) ?: null,
            'theme'            => (string) $this->request->getPost('theme'),
            'refresh_interval' => max(0, (int) $this->request->getPost('refresh_interval')),
        ]);

        AuditLogger::log(
            'dashboard.updated',
            'dashboard',
            $id,
            $oldSnap,
            [
                'name'             => strip_tags((string) $this->request->getPost('name')),
                'theme'            => (string) $this->request->getPost('theme'),
                'refresh_interval' => max(0, (int) $this->request->getPost('refresh_interval')),
            ],
            $workspaceId,
            (int) $this->session->get('user_id')
        );

        return redirect()->back()->with('success', 'Settings saved.');
    }

    public function delete(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $model = new DashboardModel();
        $dashboard = $model->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return redirect()->to('/dashboard')->with('error', 'Dashboard not found.');
        }

        $confirm = trim((string) $this->request->getPost('confirm_name'));
        if ($confirm !== (string) $dashboard['name']) {
            return redirect()->back()->with('error', 'Type the dashboard name exactly to confirm deletion.');
        }

        AuditLogger::log(
            'dashboard.deleted',
            'dashboard',
            $id,
            ['name' => $dashboard['name'] ?? null],
            null,
            $workspaceId,
            (int) $this->session->get('user_id')
        );

        $model->delete($id);

        return redirect()->to('/dashboard')->with('success', 'Dashboard deleted.');
    }

    public function pinToggle(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $model = new DashboardModel();
        $dashboard = $model->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return redirect()->to('/dashboard')->with('error', 'Dashboard not found.');
        }

        $pinned = (int) ($dashboard['is_pinned'] ?? 0) === 1;
        $model->update($id, ['is_pinned' => $pinned ? 0 : 1]);

        return redirect()->back()->with('success', 'Pin updated.');
    }

    /**
     * Batch-update widget grid positions (JSON body or form).
     */
    public function saveLayout(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $dashModel = new DashboardModel();
        $dashboard = $dashModel->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return $this->response->setJSON(['success' => false, 'message' => 'Not found.'])->setStatusCode(404);
        }

        // Do not use IncomingRequest::getJSON() here: the front-end posts
        // application/x-www-form-urlencoded (csrf + items_json), and getJSON()
        // decodes the *entire* body as JSON, which throws HTTPException.
        $items = null;
        $ct = strtolower($this->request->getHeaderLine('Content-Type'));
        if (str_contains($ct, 'application/json')) {
            $body = $this->request->getBody();
            if ($body !== null && $body !== '') {
                $decoded = json_decode($body, true);
                if (is_array($decoded)) {
                    if (isset($decoded['items']) && is_array($decoded['items'])) {
                        $items = $decoded['items'];
                    } elseif (array_is_list($decoded)) {
                        $items = $decoded;
                    }
                }
            }
        }
        if (! is_array($items)) {
            $items = json_decode((string) $this->request->getPost('items_json'), true);
        }
        if (! is_array($items)) {
            return $this->response->setJSON(['success' => false, 'message' => 'Invalid layout payload.'])->setStatusCode(422);
        }

        $widgetModel = new DashboardWidgetModel();
        $db = $widgetModel->db;
        $db->transStart();

        foreach ($items as $row) {
            if (! is_array($row)) {
                continue;
            }
            $wid = (int) ($row['id'] ?? 0);
            if ($wid <= 0) {
                continue;
            }
            $w = $widgetModel->find($wid);
            if (! $w || (int) $w['dashboard_id'] !== $id) {
                continue;
            }

            $widgetModel->update($wid, [
                'grid_x' => max(0, min(255, (int) ($row['x'] ?? 0))),
                'grid_y' => max(0, min(255, (int) ($row['y'] ?? 0))),
                'grid_w' => max(1, min(12, (int) ($row['w'] ?? 4))),
                'grid_h' => max(1, min(24, (int) ($row['h'] ?? 3))),
            ]);
        }

        // Keep DB row order aligned with visual layout (top-to-bottom, left-to-right) so PHP render matches the grid.
        $posById = [];
        foreach ($items as $row) {
            if (! is_array($row)) {
                continue;
            }
            $wid = (int) ($row['id'] ?? 0);
            if ($wid <= 0) {
                continue;
            }
            $posById[$wid] = [
                'y' => (int) ($row['y'] ?? 0),
                'x' => (int) ($row['x'] ?? 0),
            ];
        }
        $allWidgets = $widgetModel->where('dashboard_id', $id)->findAll();
        usort($allWidgets, static function (array $a, array $b) use ($posById): int {
            $ida = (int) $a['id'];
            $idb = (int) $b['id'];
            $pa = $posById[$ida] ?? null;
            $pb = $posById[$idb] ?? null;
            if ($pa !== null && $pb !== null) {
                if ($pa['y'] !== $pb['y']) {
                    return $pa['y'] <=> $pb['y'];
                }
                if ($pa['x'] !== $pb['x']) {
                    return $pa['x'] <=> $pb['x'];
                }

                return $ida <=> $idb;
            }
            if ($pa !== null) {
                return -1;
            }
            if ($pb !== null) {
                return 1;
            }

            $ya = (int) ($a['grid_y'] ?? 0);
            $yb = (int) ($b['grid_y'] ?? 0);
            if ($ya !== $yb) {
                return $ya <=> $yb;
            }
            $xa = (int) ($a['grid_x'] ?? 0);
            $xb = (int) ($b['grid_x'] ?? 0);
            if ($xa !== $xb) {
                return $xa <=> $xb;
            }

            return $ida <=> $idb;
        });
        $order = 1;
        foreach ($allWidgets as $wRow) {
            $widgetModel->update((int) $wRow['id'], ['sort_order' => $order]);
            $order++;
        }

        $db->transComplete();

        if (! $db->transStatus()) {
            return $this->response->setJSON(['success' => false, 'message' => 'Could not save layout.'])->setStatusCode(500);
        }

        return $this->response->setJSON([
            'success' => true,
            'csrf'    => ['name' => csrf_token(), 'hash' => csrf_hash()],
        ]);
    }

    public function addWidget(int $id)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $dashModel = new DashboardModel();
        $dashboard = $dashModel->findForWorkspace($id, $workspaceId);

        if (! $dashboard) {
            return $this->response->setJSON(['success' => false, 'message' => 'Not found.'])->setStatusCode(404);
        }

        $type = (string) $this->request->getPost('widget_type');
        if (! in_array($type, ['chart', 'text', 'image', 'filter_date', 'filter_dropdown'], true)) {
            return $this->response->setJSON(['success' => false, 'message' => 'Invalid widget type.'])->setStatusCode(422);
        }

        $chartId = null;
        if ($type === 'chart') {
            $chartId = (int) $this->request->getPost('chart_id');
            $chart = (new ChartModel())->where('workspace_id', $workspaceId)->find($chartId);
            if (! $chart) {
                return $this->response->setJSON(['success' => false, 'message' => 'Chart not found.'])->setStatusCode(404);
            }
        }

        $title = trim((string) $this->request->getPost('title')) ?: null;
        $content = trim((string) $this->request->getPost('content')) ?: null;
        $widgetConfig = $this->request->getPost('widget_config');

        if ($type === 'text' && ($content === null || $content === '')) {
            return $this->response->setJSON(['success' => false, 'message' => 'Text widgets need content.'])->setStatusCode(422);
        }

        if ($type === 'image' && ($content === null || $content === '')) {
            return $this->response->setJSON(['success' => false, 'message' => 'Image widgets need a URL.'])->setStatusCode(422);
        }

        if ($type === 'image' && ! $this->isSafeImageUrl((string) $content)) {
            return $this->response->setJSON(['success' => false, 'message' => 'Only http(s) image URLs are allowed.'])->setStatusCode(422);
        }

        if ($type === 'image') {
            $fit = (string) $this->request->getPost('image_fit');
            if (! in_array($fit, ['cover', 'contain', 'fill', 'scale-down'], true)) {
                $fit = 'cover';
            }
            $widgetConfig = json_encode(['object_fit' => $fit], JSON_UNESCAPED_UNICODE);
        }

        if ($type === 'filter_date') {
            $sv = preg_replace('/[^a-zA-Z0-9_]/', '', (string) $this->request->getPost('filter_start_var')) ?: 'date_from';
            $ev = preg_replace('/[^a-zA-Z0-9_]/', '', (string) $this->request->getPost('filter_end_var')) ?: 'date_to';
            $widgetConfig = json_encode(['start_var' => $sv, 'end_var' => $ev], JSON_UNESCAPED_UNICODE);
        }

        if ($type === 'filter_dropdown') {
            $vn = preg_replace('/[^a-zA-Z0-9_]/', '', (string) $this->request->getPost('filter_var_name')) ?: 'region';
            $optRaw = (string) $this->request->getPost('filter_options');
            $options = array_values(array_filter(array_map('trim', explode(',', $optRaw)), static fn ($s) => $s !== ''));
            $widgetConfig = json_encode(['var_name' => $vn, 'options' => $options], JSON_UNESCAPED_UNICODE);
        }

        $configJson = $this->normalizeWidgetConfig($widgetConfig, $type);

        $widgetModel = new DashboardWidgetModel();
        $maxRow = $widgetModel->selectMax('sort_order')->where('dashboard_id', $id)->first();
        $maxOrder = (int) ($maxRow['sort_order'] ?? 0);

        $newId = (int) $widgetModel->insert([
            'dashboard_id'  => $id,
            'chart_id'      => $chartId,
            'widget_type'   => $type,
            'title'         => $title,
            'grid_x'        => 0,
            'grid_y'        => 0,
            'grid_w'        => $type === 'chart' ? 6 : 4,
            'grid_h'        => $type === 'chart' ? 4 : 2,
            'content'       => $type === 'chart' ? null : $content,
            'widget_config' => $configJson,
            'sort_order'    => $maxOrder + 1,
        ], true);

        $row = $widgetModel->forDashboard($id);
        $created = null;
        foreach ($row as $r) {
            if ((int) $r['id'] === $newId) {
                $created = $r;
                break;
            }
        }

        return $this->response->setJSON([
            'success' => true,
            'widget'  => $created,
            'csrf'    => ['name' => csrf_token(), 'hash' => csrf_hash()],
        ]);
    }

    /**
     * Update markdown content for a text widget (AJAX).
     */
    public function updateWidget(int $widgetId)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $widgetModel = new DashboardWidgetModel();
        $w = $widgetModel->find($widgetId);

        if (! $w) {
            return $this->response->setJSON(['success' => false, 'message' => 'Widget not found.'])->setStatusCode(404);
        }

        $dashboard = (new DashboardModel())->findForWorkspace((int) $w['dashboard_id'], $workspaceId);
        if (! $dashboard) {
            return $this->response->setJSON(['success' => false, 'message' => 'Not found.'])->setStatusCode(404);
        }

        if (($w['widget_type'] ?? '') !== 'text') {
            return $this->response->setJSON(['success' => false, 'message' => 'Only text widgets can be updated here.'])->setStatusCode(422);
        }

        $content = trim((string) $this->request->getPost('content'));
        if ($content === '') {
            return $this->response->setJSON(['success' => false, 'message' => 'Content is required.'])->setStatusCode(422);
        }

        $widgetModel->update($widgetId, [
            'content' => $content,
        ]);

        $fresh = $widgetModel->find($widgetId);

        return $this->response->setJSON([
            'success' => true,
            'widget'  => [
                'id'      => (int) ($fresh['id'] ?? $widgetId),
                'content' => (string) ($fresh['content'] ?? ''),
            ],
            'csrf' => ['name' => csrf_token(), 'hash' => csrf_hash()],
        ]);
    }

    public function removeWidget(int $widgetId)
    {
        $workspaceId = (int) $this->session->get('active_workspace_id');
        $widgetModel = new DashboardWidgetModel();
        $w = $widgetModel->find($widgetId);

        if (! $w) {
            return $this->response->setJSON(['success' => false, 'message' => 'Widget not found.'])->setStatusCode(404);
        }

        $dashboard = (new DashboardModel())->findForWorkspace((int) $w['dashboard_id'], $workspaceId);
        if (! $dashboard) {
            return $this->response->setJSON(['success' => false, 'message' => 'Not found.'])->setStatusCode(404);
        }

        $widgetModel->delete($widgetId);

        return $this->response->setJSON([
            'success' => true,
            'csrf'    => ['name' => csrf_token(), 'hash' => csrf_hash()],
        ]);
    }

    private function isSafeImageUrl(string $url): bool
    {
        $url = trim($url);
        if ($url === '') {
            return false;
        }
        if (preg_match('#^https?://#i', $url) !== 1) {
            return false;
        }

        return filter_var($url, FILTER_VALIDATE_URL) !== false;
    }

    private function normalizeWidgetConfig(mixed $raw, string $type): ?string
    {
        if ($raw === null || $raw === '') {
            if ($type === 'filter_dropdown') {
                return json_encode(['var_name' => 'filter', 'options' => []], JSON_UNESCAPED_UNICODE);
            }
            if ($type === 'filter_date') {
                return json_encode(['start_var' => 'date_from', 'end_var' => 'date_to'], JSON_UNESCAPED_UNICODE);
            }
            if ($type === 'image') {
                return json_encode(['object_fit' => 'cover'], JSON_UNESCAPED_UNICODE);
            }

            return null;
        }

        if (is_string($raw)) {
            $d = json_decode($raw, true);

            return is_array($d) ? json_encode($d, JSON_UNESCAPED_UNICODE) : null;
        }

        if (is_array($raw)) {
            return json_encode($raw, JSON_UNESCAPED_UNICODE);
        }

        return null;
    }
}