<?php
defined('BASEPATH') OR exit('No direct script access allowed');

class Dashboard extends MY_Controller
{
    public function __construct()
    {
        parent::__construct();
        $this->load->library('PerformanceCacheService');
    }

    public function index()
    {
        $companyId = (int) $this->companycontext->id();
        $year = (int) date('Y');
        $summary = $this->performancecacheservice->remember(
            'dashboard:summary:' . $companyId . ':' . $year,
            300,
            function () use ($companyId, $year) {
                return $this->financialSummary($companyId, $year);
            }
        );
        $previous = $this->financialSummary($companyId, $year - 1);
        $overview = $this->operationalOverview($companyId);

        $data = array(
            'active_menu' => 'dashboard',
            'summary' => $summary,
            'comparison' => array(
                'revenue' => $this->percentageChange($summary['total_revenue'], $previous['total_revenue']),
                'expense' => $this->percentageChange($summary['total_expense'], $previous['total_expense']),
                'profit' => $this->percentageChange($summary['net_profit'], $previous['net_profit']),
            ),
            'overview' => $overview,
            'ai_insight' => $this->insights($companyId),
            'dashboard_year' => $year,
            'quick_links' => $this->quickLinks(),
            'show_financial' => is_master_admin_user()
                || check_permission('reports', 'can_view')
                || check_permission('jurnal', 'can_view'),
        );

        $this->load->view('partials/header', $data);
        $this->load->view('dashboard/layout', $data);
        $this->load->view('partials/footer');
    }

    public function get_activity()
    {
        $this->activityQuery();
        $rows = $this->db->order_by('activity_logs.created_at', 'DESC')->limit(10)->get()->result();
        return $this->json($rows);
    }

    public function log_activity()
    {
        $data = array(
            'active_menu' => 'dashboard',
            'use_datatables' => true,
        );
        $this->load->view('partials/header', $data);
        $this->load->view('dashboard/activity_logs', $data);
        $this->load->view('partials/footer');
    }

    public function get_activity_datatable()
    {
        $draw = (int) $this->input->post('draw');
        $start = max(0, (int) $this->input->post('start'));
        $length = (int) $this->input->post('length');
        $searchInput = $this->input->post('search');
        $search = is_array($searchInput) ? trim((string) ($searchInput['value'] ?? '')) : '';

        $this->activityQuery($search);
        $recordsFiltered = (int) $this->db->count_all_results();

        $this->activityQuery($search);
        $this->db->order_by('activity_logs.id', 'DESC');
        if ($length !== -1) {
            $this->db->limit(max(1, $length), $start);
        }
        $rows = $this->db->get()->result();

        $this->activityQuery();
        $recordsTotal = (int) $this->db->count_all_results();
        $result = array();
        foreach ($rows as $row) {
            $result[] = array(
                'created_at' => $row->created_at,
                'nama' => $row->nama ?: 'System',
                'module' => $row->module,
                'action' => $row->action,
                'description' => $row->description,
                'status' => $row->status,
                'ip_address' => $row->ip_address,
            );
        }

        return $this->json(array(
            'draw' => $draw,
            'recordsTotal' => $recordsTotal,
            'recordsFiltered' => $recordsFiltered,
            'data' => $result,
        ));
    }

    public function get_chart()
    {
        $year = (int) $this->input->get('year');
        if ($year < 2000 || $year > 2200) {
            $year = (int) date('Y');
        }

        $companyId = (int) $this->companycontext->id();
        $rows = $this->db->query(
            "SELECT MONTH(j.tanggal) month_no,
                    COALESCE(SUM(CASE WHEN a.tipe='revenue' THEN d.kredit-d.debit ELSE 0 END),0) revenue,
                    COALESCE(SUM(CASE WHEN a.tipe='expense' THEN d.debit-d.kredit ELSE 0 END),0) expense
             FROM journal_details d
             JOIN journals j ON j.id=d.journal_id
             JOIN accounts a ON a.id=d.account_id
             WHERE j.company_id=? AND j.status IN('posted','reversed')
               AND a.kategori='laba_rugi' AND a.is_active=1 AND YEAR(j.tanggal)=?
             GROUP BY MONTH(j.tanggal)
             ORDER BY month_no",
            array($companyId, $year)
        )->result();

        $months = array('Jan', 'Feb', 'Mar', 'Apr', 'Mei', 'Jun', 'Jul', 'Agu', 'Sep', 'Okt', 'Nov', 'Des');
        $revenue = array_fill(0, 12, 0);
        $expense = array_fill(0, 12, 0);
        foreach ($rows as $row) {
            $index = (int) $row->month_no - 1;
            if ($index >= 0 && $index < 12) {
                $revenue[$index] = (float) $row->revenue;
                $expense[$index] = (float) $row->expense;
            }
        }

        return $this->json(array(
            'year' => $year,
            'labels' => $months,
            'revenue' => $revenue,
            'expense' => $expense,
        ));
    }

    public function get_years()
    {
        $this->db->select('DISTINCT YEAR(tanggal) year', false)
            ->from('journals')
            ->where('company_id', (int) $this->companycontext->id())
            ->where_in('status', array('posted', 'reversed'))
            ->order_by('year', 'DESC');
        $years = $this->db->get()->result();
        if (!$years) {
            $years = array((object) array('year' => (int) date('Y')));
        }
        return $this->json($years);
    }

    private function financialSummary($companyId, $year)
    {
        $row = $this->db->query(
            "SELECT
                COALESCE(SUM(CASE WHEN a.tipe='revenue' THEN d.kredit-d.debit ELSE 0 END),0) total_revenue,
                COALESCE(SUM(CASE WHEN a.tipe='expense' THEN d.debit-d.kredit ELSE 0 END),0) total_expense
             FROM journal_details d
             JOIN journals j ON j.id=d.journal_id
             JOIN accounts a ON a.id=d.account_id
             WHERE j.company_id=? AND j.status IN('posted','reversed')
               AND a.kategori='laba_rugi' AND a.is_active=1 AND YEAR(j.tanggal)=?",
            array((int) $companyId, (int) $year)
        )->row_array();

        $revenue = (float) ($row['total_revenue'] ?? 0);
        $expense = (float) ($row['total_expense'] ?? 0);
        return array(
            'total_revenue' => $revenue,
            'total_expense' => $expense,
            'net_profit' => $revenue - $expense,
        );
    }

    private function operationalOverview($companyId)
    {
        $result = array(
            'receivable_amount' => 0,
            'receivable_count' => 0,
            'receivable_overdue' => 0,
            'payable_amount' => 0,
            'payable_count' => 0,
            'payable_overdue' => 0,
            'inventory_value' => 0,
            'active_items' => 0,
            'pending_items' => 0,
            'pending_approvals' => 0,
        );

        if ($this->db->table_exists('invoices')) {
            $whereDeleted = $this->db->field_exists('deleted_at', 'invoices') ? ' AND deleted_at IS NULL' : '';
            $row = $this->db->query(
                "SELECT COUNT(*) total,
                        COALESCE(SUM(sisa_piutang),0) amount,
                        SUM(CASE WHEN jatuh_tempo<CURDATE() THEN 1 ELSE 0 END) overdue
                 FROM invoices
                 WHERE company_id=? AND workflow_status='posted' AND sisa_piutang>0.001" . $whereDeleted,
                array($companyId)
            )->row();
            if ($row) {
                $result['receivable_count'] = (int) $row->total;
                $result['receivable_amount'] = (float) $row->amount;
                $result['receivable_overdue'] = (int) $row->overdue;
            }
        }

        if ($this->db->table_exists('supplier_invoices')) {
            $companyFilter = $this->db->field_exists('company_id', 'supplier_invoices')
                ? ' AND company_id=?'
                : '';
            $bindings = $companyFilter === '' ? array() : array($companyId);
            $row = $this->db->query(
                "SELECT COUNT(*) total,
                        COALESCE(SUM(balance),0) amount,
                        SUM(CASE WHEN due_date<=CURDATE() THEN 1 ELSE 0 END) overdue
                 FROM supplier_invoices
                 WHERE status='partial' AND balance>0.001" . $companyFilter,
                $bindings
            )->row();
            if ($row) {
                $result['payable_count'] = (int) $row->total;
                $result['payable_amount'] = (float) $row->amount;
                $result['payable_overdue'] = (int) $row->overdue;
            }
        }

        if ($this->db->table_exists('items')) {
            $result['active_items'] = (int) $this->db
                ->where(array('company_id' => $companyId, 'status' => 'active'))
                ->count_all_results('items');

            if ($this->db->table_exists('item_barcodes')) {
                $pending = $this->db->query(
                    "SELECT COUNT(DISTINCT i.id) total
                     FROM items i
                     LEFT JOIN item_barcodes b ON b.item_id=i.id AND b.status='pending'
                     WHERE i.company_id=? AND (i.status='draft' OR b.id IS NOT NULL)",
                    array($companyId)
                )->row();
                $result['pending_items'] = (int) ($pending ? $pending->total : 0);
            } else {
                $result['pending_items'] = (int) $this->db
                    ->where(array('company_id' => $companyId, 'status' => 'draft'))
                    ->count_all_results('items');
            }
        }

        if ($this->db->table_exists('inventory_ledger') && $this->db->field_exists('value', 'inventory_ledger')) {
            $inventory = $this->db->query(
                "SELECT COALESCE(SUM(CASE WHEN l.direction='in' THEN l.value ELSE -l.value END),0) amount
                 FROM inventory_ledger l JOIN items i ON i.id=l.item_id WHERE i.company_id=?",
                array($companyId)
            )->row();
            $result['inventory_value'] = (float) ($inventory ? $inventory->amount : 0);
        }

        if ($this->db->table_exists('approval_requests')
            && (is_master_admin_user() || check_permission('approvals', 'can_view'))) {
            $result['pending_approvals'] = (int) $this->db
                ->where('status', 'pending')
                ->count_all_results('approval_requests');
        }

        return $result;
    }

    private function insights($companyId)
    {
        if (!$this->db->table_exists('ai_insights')) {
            return array();
        }
        $this->db->select('type,severity,message,meta,created_at')
            ->where('period', date('Y-m'));
        if ($this->db->field_exists('company_id', 'ai_insights')) {
            $this->db->where('company_id', $companyId);
        }
        return $this->db
            ->order_by("CASE severity WHEN 'critical' THEN 1 WHEN 'warning' THEN 2 ELSE 3 END", '', false)
            ->order_by('created_at', 'DESC')
            ->limit(8)
            ->get('ai_insights')
            ->result();
    }

    private function quickLinks()
    {
        $definitions = array(
            array('feature' => 'invoices', 'action' => 'can_create', 'label' => 'Buat Invoice', 'description' => 'Catat tagihan penjualan', 'icon' => 'bi-receipt-cutoff', 'url' => 'invoices/create'),
            array('feature' => 'purchases', 'action' => 'can_create', 'label' => 'Purchase Workflow', 'description' => 'Buat permintaan pembelian', 'icon' => 'bi-cart-plus', 'url' => 'purchases'),
            array('feature' => 'jurnal', 'action' => 'can_create', 'label' => 'Jurnal Umum', 'description' => 'Catat jurnal manual', 'icon' => 'bi-journal-plus', 'url' => 'jurnal'),
            array('feature' => 'items', 'action' => 'can_view', 'label' => 'Scan Persediaan', 'description' => 'Periksa barcode dan stok', 'icon' => 'bi-qr-code-scan', 'url' => 'inventoryprofessional#scanner'),
        );

        $links = array();
        foreach ($definitions as $definition) {
            if (is_master_admin_user() || check_permission($definition['feature'], $definition['action'])) {
                $links[] = $definition;
            }
        }
        return $links;
    }

    private function activityQuery($search = '')
    {
        $this->db->select('activity_logs.*,users.nama')
            ->from('activity_logs')
            ->join('users', 'users.id=activity_logs.user_id', 'left');

        if ($this->db->field_exists('company_id', 'activity_logs')) {
            $this->db->where('activity_logs.company_id', (int) $this->companycontext->id());
        } elseif (!is_master_admin_user()) {
            $this->db->where('activity_logs.user_id', (int) $this->session->userdata('user_id'));
        }

        if ($search !== '') {
            $this->db->group_start()
                ->like('activity_logs.module', $search)
                ->or_like('activity_logs.action', $search)
                ->or_like('activity_logs.description', $search)
                ->or_like('activity_logs.status', $search)
                ->or_like('users.nama', $search)
                ->group_end();
        }
    }

    private function percentageChange($current, $previous)
    {
        $previous = (float) $previous;
        if (abs($previous) < 0.01) {
            return null;
        }
        return round((((float) $current - $previous) / abs($previous)) * 100, 1);
    }

    private function json($payload)
    {
        return $this->output
            ->set_content_type('application/json', 'utf-8')
            ->set_output(json_encode($payload, JSON_UNESCAPED_UNICODE));
    }
}