@extends('layouts.app')

@section('title', 'Аналитика')

{{--
    Ports app/Views/analytics/index.php (legacy) — see the Phase 49 plan.
    The ЕНТ score entry form uses Laravel's own $errors/old() — confirmed
    safe since the legacy view genuinely repopulates old input here (via
    Old::get()/Old::hasError()/Old::error()).
--}}

@push('styles')
<style>
    .stat-card { border-radius: 12px; transition: .15s; }
    .stat-card:hover { transform: translateY(-2px); }
    .big-number { font-size: 1.6rem; font-weight: 600; }
    .section-title { margin: 2rem 0 1rem; }
</style>
@endpush

@section('content')
<div class="container mt-4 pb-5">

    <!-- ── Period picker ─────────────────────────────────────────── -->
    <div class="d-flex align-items-center gap-3 mb-3 flex-wrap">
        <h2 class="mb-0">Аналитика</h2>
        <div class="d-flex align-items-center gap-2 ms-auto">
            <a href="?year={{ $prevYear }}&month={{ $prevMonth }}"
               class="btn btn-outline-secondary btn-sm">&larr;</a>

            <form method="GET" action="/analytics.php" class="d-flex gap-2 align-items-center">
                @php
                    $monthNames = ['Январь','Февраль','Март','Апрель','Май','Июнь',
                                   'Июль','Август','Сентябрь','Октябрь','Ноябрь','Декабрь'];
                @endphp
                <select name="month" class="form-select form-select-sm" style="width:130px;" onchange="this.form.submit()">
                    @foreach ($monthNames as $i => $mn)
                        <option value="{{ $i + 1 }}" @selected($i + 1 === $month)>{{ $mn }}</option>
                    @endforeach
                </select>
                <select name="year" class="form-select form-select-sm" style="width:90px;" onchange="this.form.submit()">
                    @for ($y = date('Y'); $y >= 2023; $y--)
                        <option value="{{ $y }}" @selected($y === $year)>{{ $y }}</option>
                    @endfor
                </select>
            </form>

            <a href="?year={{ $nextYear }}&month={{ $nextMonth }}"
               class="btn btn-outline-secondary btn-sm">&rarr;</a>
        </div>
    </div>
    <p class="text-muted small">Период применяется к метрикам за месяц. Отдельные показатели помечены как «на данный момент».</p>

    <!-- ══════════════════════════ 1. ОБЗОР ══════════════════════════ -->
    @if ($overview)
    <h4 class="section-title">Обзор</h4>
    <div class="row g-3 mb-4">
        <div class="col-6 col-md-3">
            <div class="card stat-card border-success shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Активных учеников (сейчас)</div>
                    <div class="big-number text-success">{{ $overview['active_students'] }}</div>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-secondary shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Активных на дату</div>
                    <div class="big-number">{{ $overview['active_students_asof'] }}</div>
                    <form method="GET" action="/analytics.php" class="d-flex gap-1 mt-1">
                        <input type="hidden" name="year" value="{{ $year }}">
                        <input type="hidden" name="month" value="{{ $month }}">
                        <input type="date" name="as_of" class="form-control form-control-sm"
                               value="{{ $asOfDate }}" onchange="this.form.submit()">
                    </form>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-info shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Средняя заполняемость группы</div>
                    <div class="big-number text-info">{{ $overview['avg_group_size'] }}</div>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-primary shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Ср. предметов на ученика</div>
                    <div class="big-number text-primary">{{ $overview['avg_disciplines'] }}</div>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-warning shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Загрузка мощностей</div>
                    <div class="big-number text-warning">{{ $overview['capacity_utilization'] }}%</div>
                </div>
            </div>
        </div>
        @isset($overview['overdue_count'])
        <div class="col-6 col-md-3">
            <div class="card stat-card border-danger shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Просрочки (сейчас)</div>
                    <div class="big-number text-danger">{{ $overview['overdue_count'] }}</div>
                </div>
            </div>
        </div>
        @endisset
    </div>
    @endif

    <!-- ══════════════════════════ ТРЕНДЫ ══════════════════════════ -->
    @if ($trends)
    <h4 class="section-title">Тренды за 6 месяцев</h4>
    <div class="row g-3 mb-4">
        <div class="col-12 {{ isset($trends['revenue']) ? 'col-lg-6' : '' }}">
            <div class="card shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-2">Активных учеников</div>
                    <canvas id="trendActiveStudents" height="90"></canvas>
                </div>
            </div>
        </div>
        @isset($trends['revenue'])
        <div class="col-12 col-lg-6">
            <div class="card shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-2">Выручка, ₸</div>
                    <canvas id="trendRevenue" height="90"></canvas>
                </div>
            </div>
        </div>
        @endisset
    </div>
    @endif

    <!-- ══════════════════════ УЧЕНИКИ ГРУППЫ РИСКА ══════════════════════ -->
    @if ($atRisk && (!empty($atRisk['overdue']) || !empty($atRisk['low_nps'])))
    @php $atRiskCount = count($atRisk['overdue']) + count($atRisk['low_nps']); @endphp
    <h4 class="section-title">Ученики группы риска</h4>
    <div class="row g-3 mb-4">
        <div class="col-6 col-md-3">
            <div class="card stat-card border-danger shadow-sm h-100" role="button" tabindex="0"
                 style="cursor:pointer;" data-bs-toggle="modal" data-bs-target="#atRiskModal">
                <div class="card-body">
                    <div class="small text-muted mb-1">Ученики группы риска</div>
                    <div class="big-number text-danger">{{ $atRiskCount }}</div>
                    <div class="small text-primary">Показать список &rarr;</div>
                </div>
            </div>
        </div>
    </div>

    <div class="modal fade" id="atRiskModal" tabindex="-1" aria-hidden="true">
        <div class="modal-dialog modal-lg modal-dialog-scrollable">
            <div class="modal-content">
                <div class="modal-header">
                    <h5 class="modal-title">Ученики группы риска</h5>
                    <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Закрыть"></button>
                </div>
                <div class="modal-body">
                    <div class="table-responsive">
                        <table class="table table-sm table-hover align-middle mb-0">
                            <thead>
                                <tr>
                                    <th>Ученик</th>
                                    <th>Телефон</th>
                                    <th>Причина</th>
                                </tr>
                            </thead>
                            <tbody>
                                @foreach ($atRisk['overdue'] as $student)
                                    @php $balance = (float) $student['total_paid'] - (float) $student['total_charged']; @endphp
                                    <tr>
                                        <td>{{ $student['last_name'] . ' ' . $student['first_name'] }}</td>
                                        <td>{{ $student['phone'] ?? '—' }}</td>
                                        <td>
                                            <span class="badge bg-danger">
                                                Задолженность {{ number_format(abs($balance), 0, '.', ' ') }} ₸
                                            </span>
                                        </td>
                                    </tr>
                                @endforeach
                                @foreach ($atRisk['low_nps'] as $response)
                                    <tr>
                                        <td>{{ $response['last_name'] . ' ' . $response['first_name'] }}</td>
                                        <td>—</td>
                                        <td><span class="badge bg-warning text-dark">Низкий NPS: {{ (int) $response['score'] }}</span></td>
                                    </tr>
                                @endforeach
                            </tbody>
                        </table>
                    </div>
                </div>
                <div class="modal-footer">
                    <a href="/admin/export_at_risk_students.csv" class="btn btn-outline-secondary btn-sm">Экспорт CSV</a>
                    <button type="button" class="btn btn-secondary btn-sm" data-bs-dismiss="modal">Закрыть</button>
                </div>
            </div>
        </div>
    </div>
    @endif

    <!-- ══════════════════════ 2. ОПЛАТЫ И ВЫРУЧКА ══════════════════════ -->
    @if ($payments)
    <h4 class="section-title">Оплаты и выручка</h4>
    <div class="row g-3 mb-4">
        <div class="col-6 col-md-3">
            <div class="card stat-card border-success shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Средний чек новых учеников</div>
                    <div class="big-number text-success">{{ number_format($payments['new_student_arpu'], 0, ',', ' ') }} ₸</div>
                    <div class="small text-muted">{{ $payments['new_student_count'] }} новых оплат</div>
                </div>
            </div>
        </div>
        @isset($payments['overall_arpu'])
        <div class="col-6 col-md-3">
            <div class="card stat-card border-info shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Общий средний чек</div>
                    <div class="big-number text-info">{{ number_format($payments['overall_arpu'], 0, ',', ' ') }} ₸</div>
                </div>
            </div>
        </div>
        @endisset
        <div class="col-6 col-md-3">
            <div class="card stat-card border-primary shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">% продления после 1-й оплаты</div>
                    <div class="big-number text-primary">{{ $payments['renewal_after_first']['rate'] }}%</div>
                    <div class="small text-muted">
                        {{ $payments['renewal_after_first']['renewed'] }} из {{ $payments['renewal_after_first']['first_time_payers'] }}
                    </div>
                </div>
            </div>
        </div>
        @isset($payments['period_retention'])
        <div class="col-6 col-md-3">
            <div class="card stat-card border-primary shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">% продления в целом</div>
                    <div class="big-number text-primary">{{ $payments['period_retention']['rate'] }}%</div>
                    <div class="small text-muted">
                        {{ $payments['period_retention']['retained'] }} из {{ $payments['period_retention']['prev_payers'] }} (пред. период)
                    </div>
                </div>
            </div>
        </div>
        @endisset
        @isset($payments['charges_total'])
        <div class="col-6 col-md-3">
            <div class="card stat-card border-dark shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Начисления за месяц</div>
                    <div class="big-number">{{ number_format($payments['charges_total'], 0, ',', ' ') }} ₸</div>
                </div>
            </div>
        </div>
        @endisset
    </div>
    @endif

    <!-- ══════════════════════════ 3. ФИНАНСЫ ══════════════════════════ -->
    @if ($finance)
    <h4 class="section-title">Финансы</h4>
    <div class="row g-3 mb-4">
        <div class="col-6 col-md-3">
            <div class="card stat-card border-{{ $finance['net_profit'] >= 0 ? 'success' : 'danger' }} shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Чистая прибыль за месяц</div>
                    <div class="big-number {{ $finance['net_profit'] >= 0 ? 'text-success' : 'text-danger' }}">
                        {{ number_format($finance['net_profit'], 0, ',', ' ') }} ₸
                    </div>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-warning shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">CAC (стоимость клиента)</div>
                    <div class="big-number text-warning">{{ number_format($finance['cac'], 0, ',', ' ') }} ₸</div>
                    <div class="small text-muted">маркетинг {{ number_format($finance['marketing_spend'], 0, ',', ' ') }} ₸</div>
                </div>
            </div>
        </div>
    </div>
    <div class="row g-3 mb-4">
        <div class="col-md-6">
            <div class="card shadow-sm h-100">
                <div class="card-header"><strong>Доли расходов по категориям</strong></div>
                <div class="card-body">
                    @if (empty($finance['expenses_by_category']))
                        <p class="text-muted mb-0">Нет расходов за этот период.</p>
                    @else
                        <canvas id="expenseChart" height="220"></canvas>
                    @endif
                </div>
            </div>
        </div>
        <div class="col-md-6">
            <div class="card shadow-sm h-100">
                <div class="card-header"><strong>Доли выручки по дисциплинам</strong></div>
                <div class="card-body">
                    @if (empty($finance['revenue_by_discipline']))
                        <p class="text-muted mb-0">Нет начислений за этот период.</p>
                    @else
                        <canvas id="revenueChart" height="220"></canvas>
                    @endif
                </div>
            </div>
        </div>
    </div>
    @endif

    <!-- ═════════════ 4. ПРЕПОДАВАТЕЛИ / ЗАМЕНЫ / КУРАТОРЫ ═════════════ -->
    @if ($teachers)
    <h4 class="section-title">Преподаватели, замены, кураторы</h4>
    <div class="row g-3 mb-4">
        @isset($teachers['substitutions_count'])
        <div class="col-6 col-md-3">
            <div class="card stat-card border-secondary shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Замен за период</div>
                    <div class="big-number">{{ $teachers['substitutions_count'] }}</div>
                </div>
            </div>
        </div>
        @endisset
        <div class="col-6 col-md-3">
            <div class="card stat-card border-info shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Ср. прогресс по ЕНТ</div>
                    <div class="big-number {{ $teachers['ent_progress']['avg_delta'] >= 0 ? 'text-success' : 'text-danger' }}">
                        {{ ($teachers['ent_progress']['avg_delta'] >= 0 ? '+' : '') . $teachers['ent_progress']['avg_delta'] }}
                    </div>
                    <div class="small text-muted">{{ $teachers['ent_progress']['count'] }} учеников с 2+ результатами</div>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-primary shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">NPS (последний)</div>
                    <div class="big-number text-primary">{{ $teachers['nps_latest'] }}</div>
                </div>
            </div>
        </div>
        <div class="col-6 col-md-3">
            <div class="card stat-card border-success shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Выполнение задач куратором</div>
                    @php $cc = $teachers['curator_completion']; $ccOverall = $cc['overall'] ?? $cc; @endphp
                    <div class="big-number text-success">{{ $ccOverall['rate'] }}%</div>
                    <div class="small text-muted">{{ $ccOverall['resolved'] }} из {{ $ccOverall['total'] }}</div>
                </div>
            </div>
        </div>
        @isset($teachers['total_salary'])
        <div class="col-6 col-md-3">
            <div class="card stat-card border-dark shadow-sm h-100">
                <div class="card-body">
                    <div class="small text-muted mb-1">Зарплата за месяц</div>
                    <div class="big-number">{{ number_format($teachers['total_salary'], 0, ',', ' ') }} ₸</div>
                    <a href="/admin/teachers_count.php" class="small">по преподавателям &rarr;</a>
                </div>
            </div>
        </div>
        @endisset
    </div>

    @if (!empty($teachers['substitutions_by_teacher']))
    <div class="card shadow-sm mb-4">
        <div class="card-header"><strong>Замены по преподавателям</strong></div>
        <div class="table-responsive">
            <table class="table table-hover align-middle mb-0">
                <thead class="table-light">
                    <tr><th>Преподаватель</th><th class="text-center">Заменил</th><th class="text-center">Заменился</th></tr>
                </thead>
                <tbody>
                @foreach ($teachers['substitutions_by_teacher'] as $row)
                    <tr>
                        <td>{{ $row['teacher_name'] }}</td>
                        <td class="text-center">{{ $row['covered_for_others'] }}</td>
                        <td class="text-center">{{ $row['was_covered'] }}</td>
                    </tr>
                @endforeach
                </tbody>
            </table>
        </div>
    </div>
    @endif

    @if (!empty($teachers['performance']))
    <div class="card shadow-sm mb-4">
        <div class="card-header"><strong>Показатели учителей</strong></div>
        <div class="table-responsive">
            <table class="table table-sm table-hover align-middle mb-0">
                <thead class="table-light">
                    <tr>
                        <th>Учитель</th>
                        <th class="text-center">Уроков</th>
                        <th class="text-center">Часы</th>
                        <th class="text-center">Заработок</th>
                        <th class="text-center">Выручка группы</th>
                        <th class="text-center">Посещаемость</th>
                        <th class="text-center">Ср. ДЗ</th>
                        <th class="text-center">Ср. КР</th>
                        <th class="text-center">Замены</th>
                    </tr>
                </thead>
                <tbody>
                @foreach ($teachers['performance'] as $row)
                    <tr>
                        <td>{{ $row['teacher_name'] }}</td>
                        <td class="text-center">{{ (int) $row['lessons_count'] }}</td>
                        <td class="text-center">{{ number_format((float) $row['hours'], 1, ',', ' ') }}</td>
                        <td class="text-center">{{ number_format((float) $row['earnings'], 0, ',', ' ') }} ₸</td>
                        <td class="text-center">{{ number_format((float) $row['revenue'], 0, ',', ' ') }} ₸</td>
                        <td class="text-center">{{ $row['attendance_pct'] !== null ? (int) $row['attendance_pct'] . '%' : '—' }}</td>
                        <td class="text-center">{{ $row['avg_dz'] ?? '—' }}</td>
                        <td class="text-center">{{ $row['avg_kr'] ?? '—' }}</td>
                        <td class="text-center">{{ $row['covered_for_others'] }} / {{ $row['was_covered'] }}</td>
                    </tr>
                @endforeach
                </tbody>
            </table>
        </div>
    </div>
    @endif

    @if (isset($cc['by_curator']) && !empty($cc['by_curator']))
    <div class="card shadow-sm mb-4">
        <div class="card-header"><strong>Выполнение задач по кураторам</strong></div>
        <div class="table-responsive">
            <table class="table table-hover align-middle mb-0">
                <thead class="table-light">
                    <tr><th>Куратор</th><th class="text-center">Выполнено</th><th class="text-center">Всего</th><th class="text-center">%</th></tr>
                </thead>
                <tbody>
                @foreach ($cc['by_curator'] as $row)
                    <tr>
                        <td>{{ $row['curator_name'] }}</td>
                        <td class="text-center">{{ $row['resolved'] }}</td>
                        <td class="text-center">{{ $row['total'] }}</td>
                        <td class="text-center">{{ $row['rate'] }}%</td>
                    </tr>
                @endforeach
                </tbody>
            </table>
        </div>
    </div>
    @endif

    @if (isset($teachers['nps_detail']) && !empty($teachers['nps_detail']))
    <div class="card shadow-sm mb-4">
        <div class="card-header"><strong>NPS — детализация</strong></div>
        <div class="table-responsive">
            <table class="table table-hover align-middle mb-0">
                <thead class="table-light">
                    <tr><th>Ученик</th><th class="text-center">Оценка</th><th>Комментарий</th><th>Дата</th></tr>
                </thead>
                <tbody>
                @foreach ($teachers['nps_detail'] as $row)
                    <tr>
                        <td>{{ $row['first_name'] . ' ' . $row['last_name'] }}</td>
                        <td class="text-center">{{ (int) $row['score'] }}</td>
                        <td>{{ $row['comment'] ?? '—' }}</td>
                        <td>{{ $row['created_at'] }}</td>
                    </tr>
                @endforeach
                </tbody>
            </table>
        </div>
    </div>
    @endif

    @endif

</div>
@endsection

@push('scripts')
<script src="https://cdn.jsdelivr.net/npm/chart.js@4.4.4/dist/chart.umd.min.js"></script>
@if ($trends)
<script>
document.addEventListener('DOMContentLoaded', () => {
    const labels = {!! json_encode($trends['labels']) !!};

    new Chart(document.getElementById('trendActiveStudents'), {
        type: 'line',
        data: {
            labels: labels,
            datasets: [{
                label: 'Активных учеников',
                data: {!! json_encode(array_map('intval', $trends['active_students'])) !!},
                borderColor: '#0d6efd',
                backgroundColor: 'rgba(13,110,253,.1)',
                tension: .3,
                fill: true,
            }]
        },
        options: { plugins: { legend: { display: false } } }
    });

    @isset($trends['revenue'])
    new Chart(document.getElementById('trendRevenue'), {
        type: 'line',
        data: {
            labels: labels,
            datasets: [{
                label: 'Выручка',
                data: {!! json_encode(array_map('floatval', $trends['revenue'])) !!},
                borderColor: '#198754',
                backgroundColor: 'rgba(25,135,84,.1)',
                tension: .3,
                fill: true,
            }]
        },
        options: { plugins: { legend: { display: false } } }
    });
    @endisset
});
</script>
@endif

@if ($finance && !empty($finance['expenses_by_category']))
<script>
document.addEventListener('DOMContentLoaded', () => {
    new Chart(document.getElementById('expenseChart'), {
        type: 'doughnut',
        data: {
            labels: {!! json_encode(array_column($finance['expenses_by_category'], 'category'), JSON_UNESCAPED_UNICODE) !!},
            datasets: [{
                data: {!! json_encode(array_map('floatval', array_column($finance['expenses_by_category'], 'total'))) !!},
            }]
        },
        options: { plugins: { legend: { position: 'bottom' } } }
    });
});
</script>
@endif

@if ($finance && !empty($finance['revenue_by_discipline']))
<script>
document.addEventListener('DOMContentLoaded', () => {
    new Chart(document.getElementById('revenueChart'), {
        type: 'doughnut',
        data: {
            labels: {!! json_encode(array_column($finance['revenue_by_discipline'], 'discipline_name'), JSON_UNESCAPED_UNICODE) !!},
            datasets: [{
                data: {!! json_encode(array_map('floatval', array_column($finance['revenue_by_discipline'], 'revenue'))) !!},
            }]
        },
        options: { plugins: { legend: { position: 'bottom' } } }
    });
});
</script>
@endif
@endpush