<?php

namespace Modules\ProjectReports\Http\Controllers;

use App\Http\Controllers\Controller;
use App\Models\User;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Inertia\Inertia;
use Modules\ApprovalWorkflow\Services\ApprovalService;
use Modules\ProjectManagement\Enums\DelayReason;
use Modules\ProjectManagement\Enums\ReportStatus;
use Modules\ProjectManagement\Enums\WeatherCondition;
use Modules\ProjectManagement\Models\HseRecord;
use Modules\ProjectManagement\Models\Project;
use Modules\ProjectManagement\Models\TaskDelay;
use Modules\ProjectManagement\Models\WeeklyStatusReport;
use Modules\ProjectManagement\Models\WorkforceMetric;

class StatusReportController extends Controller
{
    public function __construct(
        private ApprovalService $approvalService,
    ) {}

    public function index(Request $request, Project $project)
    {
        $reports = $project->statusReports()
            ->with(['workforceMetric', 'hseRecord', 'submitter:id,name'])
            ->when($request->status, fn ($q, $s) => $q->where('status', $s))
            ->paginate(15)
            ->withQueryString();

        return Inertia::render('ProjectReports::Reports/Index', [
            'project' => $project->load('status'), // we need status for transitions if we want to show it
            'reports' => $reports,
            'filters' => $request->only(['status']),
            'statuses' => collect(ReportStatus::cases())->map(fn ($s) => [
                'value' => $s->value,
                'label' => $s->label(),
            ]),
            'allowedTransitions' => collect($project->status->allowedTransitions())->map(fn ($s) => [
                'value' => $s->value,
                'label' => $s->label(),
            ]),
        ]);
    }

    public function create(Project $project)
    {
        $latestReport = $project->statusReports()->first();

        $defaultStart = $latestReport
            ? $latestReport->period_end->addDay()->format('Y-m-d')
            : ($project->start_date?->format('Y-m-d') ?? now()->format('Y-m-d'));

        return Inertia::render('ProjectManagement::Reports/Create', [
            'project' => $project->only('id', 'name', 'code'),
            'defaultPeriodStart' => $defaultStart,
            'defaultPeriodEnd' => now()->format('Y-m-d'),
        ]);
    }

    public function store(Request $request, Project $project)
    {
        $validated = $this->validateReport($request);

        $report = DB::transaction(function () use ($validated, $project, $request) {
            $report = $project->statusReports()->create([
                'period_start' => $validated['period_start'],
                'period_end' => $validated['period_end'],
                'narrative_status' => $validated['narrative_status'] ?? null,
                'narrative_weather' => $validated['narrative_weather'] ?? null,
                'narrative_compliance' => $validated['narrative_compliance'] ?? null,
                'submitted_by' => $request->user()->id,
            ]);

            $periodManHours = (float) ($validated['period_man_hours'] ?? 0);
            $cumulative = WorkforceMetric::calculateCumulative(
                $project->id,
                $validated['period_start'],
                $periodManHours,
            );

            $report->workforceMetric()->create([
                'active_workforce' => $validated['active_workforce'] ?? 0,
                'period_man_hours' => $periodManHours,
                'cumulative_man_hours' => $cumulative,
                'logistics_km' => $validated['logistics_km'] ?? 0,
            ]);

            $report->hseRecord()->create([
                'toolbox_meetings' => $validated['toolbox_meetings'] ?? 0,
                'safety_observations' => $validated['safety_observations'] ?? 0,
                'fatalities' => $validated['fatalities'] ?? 0,
                'major_injuries' => $validated['major_injuries'] ?? 0,
                'first_aid_cases' => $validated['first_aid_cases'] ?? 0,
                'medical_cases' => $validated['medical_cases'] ?? 0,
                'near_misses' => $validated['near_misses'] ?? 0,
                'environmental_damage' => $validated['environmental_damage'] ?? 0,
                'property_damage' => $validated['property_damage'] ?? 0,
                'fines' => $validated['fines'] ?? 0,
            ]);

            return $report;
        });

        // Auto-populate weather from task delays if user left fields empty
        $this->autoPopulateWeather($report, $project);

        return redirect()->route('projects.reports.show', [$project, $report])
            ->with('success', 'Status report created.');
    }

    public function show(Project $project, WeeklyStatusReport $report)
    {
        $report->load([
            'workforceMetric',
            'hseRecord',
            'submitter:id,name',
            'approver:id,name',
            'approvalChains.steps.approver:id,name',
        ]);

        return Inertia::render('ProjectManagement::Reports/Show', [
            'project' => $project->load(['customer:id,name', 'contractor:id,company_name']),
            'report' => $report,
        ]);
    }

    public function edit(Project $project, WeeklyStatusReport $report)
    {
        if (!in_array($report->status, [ReportStatus::Draft, ReportStatus::Rejected])) {
            return back()->with('error', 'Only draft or rejected reports can be edited.');
        }

        $report->load(['workforceMetric', 'hseRecord']);

        return Inertia::render('ProjectManagement::Reports/Edit', [
            'project' => $project->only('id', 'name', 'code'),
            'report' => $report,
        ]);
    }

    public function update(Request $request, Project $project, WeeklyStatusReport $report)
    {
        if (!in_array($report->status, [ReportStatus::Draft, ReportStatus::Rejected])) {
            return back()->with('error', 'Only draft or rejected reports can be edited.');
        }

        $validated = $this->validateReport($request);

        DB::transaction(function () use ($validated, $project, $report) {
            $report->update([
                'period_start' => $validated['period_start'],
                'period_end' => $validated['period_end'],
                'narrative_status' => $validated['narrative_status'] ?? null,
                'narrative_weather' => $validated['narrative_weather'] ?? null,
                'narrative_compliance' => $validated['narrative_compliance'] ?? null,
                'status' => ReportStatus::Draft, // reset to draft on edit
            ]);

            $periodManHours = (float) ($validated['period_man_hours'] ?? 0);
            $cumulative = WorkforceMetric::calculateCumulative(
                $project->id,
                $validated['period_start'],
                $periodManHours,
                $report->id,
            );

            $report->workforceMetric()->updateOrCreate(
                ['weekly_status_report_id' => $report->id],
                [
                    'active_workforce' => $validated['active_workforce'] ?? 0,
                    'period_man_hours' => $periodManHours,
                    'cumulative_man_hours' => $cumulative,
                    'logistics_km' => $validated['logistics_km'] ?? 0,
                ]
            );

            $report->hseRecord()->updateOrCreate(
                ['weekly_status_report_id' => $report->id],
                [
                    'toolbox_meetings' => $validated['toolbox_meetings'] ?? 0,
                    'safety_observations' => $validated['safety_observations'] ?? 0,
                    'fatalities' => $validated['fatalities'] ?? 0,
                    'major_injuries' => $validated['major_injuries'] ?? 0,
                    'first_aid_cases' => $validated['first_aid_cases'] ?? 0,
                    'medical_cases' => $validated['medical_cases'] ?? 0,
                    'near_misses' => $validated['near_misses'] ?? 0,
                    'environmental_damage' => $validated['environmental_damage'] ?? 0,
                    'property_damage' => $validated['property_damage'] ?? 0,
                    'fines' => $validated['fines'] ?? 0,
                ]
            );
        });

        // Auto-populate weather from task delays if user left fields empty
        $this->autoPopulateWeather($report, $project);

        return redirect()->route('projects.reports.show', [$project, $report])
            ->with('success', 'Status report updated.');
    }

    public function submitForApproval(Request $request, Project $project, WeeklyStatusReport $report)
    {
        if ($report->status !== ReportStatus::Draft) {
            return back()->with('error', 'Only draft reports can be submitted for approval.');
        }

        $report->transitionTo(ReportStatus::Submitted);

        // Get PM as the approver
        $pm = $project->personnel()->wherePivot('role', 'pm')->first();

        if (!$pm) {
            return back()->with('error', 'No Project Manager assigned. Cannot submit for approval.');
        }

        $this->approvalService->createChain(
            approvable: $report,
            approverIds: [$pm->id],
            type: 'weekly_status_report',
            initiatedBy: $request->user()->id,
            notes: "Weekly status report for {$report->period_label}",
        );

        $report->transitionTo(ReportStatus::InReview);

        return back()->with('success', 'Report submitted for approval.');
    }

    public function destroy(Project $project, WeeklyStatusReport $report)
    {
        if ($report->status !== ReportStatus::Draft) {
            return back()->with('error', 'Only draft reports can be deleted.');
        }

        $report->delete();

        return redirect()->route('projects.reports.index', $project)
            ->with('success', 'Report deleted.');
    }

    private function validateReport(Request $request): array
    {
        return $request->validate([
            'period_start' => 'required|date',
            'period_end' => 'required|date|after_or_equal:period_start',
            // Narrative
            'narrative_status' => 'nullable|string|max:2000',
            'narrative_weather' => 'nullable|string|max:2000',
            'narrative_compliance' => 'nullable|string|max:2000',
            // Structured weather
            'weather_work_days_lost' => 'nullable|integer|min:0',
            'weather_conditions' => 'nullable|array',
            'weather_conditions.*' => 'string',
            // Workforce
            'active_workforce' => 'nullable|integer|min:0',
            'period_man_hours' => 'nullable|numeric|min:0',
            'logistics_km' => 'nullable|numeric|min:0',
            // HSE Proactive
            'toolbox_meetings' => 'nullable|integer|min:0',
            'safety_observations' => 'nullable|integer|min:0',
            // HSE Reactive
            'fatalities' => 'nullable|integer|min:0',
            'major_injuries' => 'nullable|integer|min:0',
            'first_aid_cases' => 'nullable|integer|min:0',
            'medical_cases' => 'nullable|integer|min:0',
            'near_misses' => 'nullable|integer|min:0',
            'environmental_damage' => 'nullable|integer|min:0',
            'property_damage' => 'nullable|integer|min:0',
            'fines' => 'nullable|numeric|min:0',
        ]);
    }

    private function autoPopulateWeather(WeeklyStatusReport $report, Project $project): void
    {
        $delays = TaskDelay::whereIn('task_id', $project->tasks()->pluck('id'))
            ->where('reason_type', DelayReason::Weather)
            ->whereBetween('delay_date', [$report->period_start, $report->period_end])
            ->get();

        if ($delays->isEmpty()) return;

        $totalHours = (float) $delays->sum('lost_hours');
        $daysLost = (int) ceil($totalHours / 8);
        $conditions = $delays->pluck('weather_condition')
            ->filter()
            ->map(fn ($c) => $c instanceof WeatherCondition ? $c->value : $c)
            ->unique()
            ->values()
            ->toArray();

        $updates = [];

        if ($report->weather_work_days_lost === 0 && $daysLost > 0) {
            $updates['weather_work_days_lost'] = $daysLost;
        }

        if (empty($report->weather_conditions) && !empty($conditions)) {
            $updates['weather_conditions'] = $conditions;
        }

        // Auto-generate narrative if empty
        if (empty($report->narrative_weather) && !empty($conditions)) {
            $labels = collect($conditions)->map(fn ($v) => WeatherCondition::tryFrom($v)?->label() ?? $v)->join(', ');
            $updates['narrative_weather'] = "Weather delays recorded: {$labels}. Total {$daysLost} work day(s) lost ({$totalHours} hours).";
        }

        if (!empty($updates)) {
            $report->update($updates);
        }
    }
}