<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Http\Requests\StoreDocumentTemplateRequest;
use App\Http\Requests\UpdateDocumentTemplateRequest;
use App\Models\Action;
use App\Models\DocumentTemplate;
use App\Services\Documents\TokenScanner;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Gate;
use Illuminate\Support\Facades\Schema;
use Illuminate\Support\Str;
use Inertia\Inertia;

class DocumentTemplateController extends Controller
{
    public function index()
    {
        $this->ensurePermission();
        $templates = DocumentTemplate::query()->orderByDesc('updated_at')->get();
        $actions = Action::with(['decisions:id,name'])->orderBy('name')->get(['id', 'name']);
        $actionsMapped = $actions->map(fn ($a) => [
            'id' => $a->id,
            'name' => $a->name,
            'decisions' => $a->decisions->map(fn ($d) => ['id' => $d->id, 'name' => $d->name])->values(),
        ]);

        return Inertia::render('Admin/DocumentTemplates/Index', [
            'templates' => $templates,
            'actions' => $actionsMapped,
        ]);
    }

    public function toggleActive(DocumentTemplate $template)
    {
        $this->ensurePermission();
        $template->active = ! $template->active;
        $template->updated_by = Auth::id();
        $template->save();

        return redirect()->back()->with('success', 'Status predloge posodobljen.');
    }

    public function show(DocumentTemplate $template)
    {
        $this->ensurePermission();

        return Inertia::render('Admin/DocumentTemplates/Show', [
            'template' => $template,
        ]);
    }

    public function edit(DocumentTemplate $template)
    {
        $this->ensurePermission();
        $actions = Action::with(['decisions:id,name'])->orderBy('name')->get(['id', 'name']);
        $actionsMapped = $actions->map(fn ($a) => [
            'id' => $a->id,
            'name' => $a->name,
            'decisions' => $a->decisions->map(fn ($d) => ['id' => $d->id, 'name' => $d->name])->values(),
        ]);

        return Inertia::render('Admin/DocumentTemplates/Edit', [
            'template' => $template,
            'actions' => $actionsMapped,
        ]);
    }

    public function updateSettings(UpdateDocumentTemplateRequest $request, DocumentTemplate $template)
    {
        $this->ensurePermission();
        $template->fill($request->only([
            'output_filename_pattern', 'date_format', 'action_id', 'decision_id', 'activity_note_template',
        ]));
        // If both action & decision provided, ensure decision belongs to action (parity with import templates)
        if ($request->filled('action_id') && $request->filled('decision_id')) {
            $belongs = \DB::table('action_decision')
                ->where('action_id', $request->integer('action_id'))
                ->where('decision_id', $request->integer('decision_id'))
                ->exists();
            if (! $belongs) {
                return redirect()->back()->withErrors(['decision_id' => 'Izbrana odločitev ne pripada izbrani akciji.']);
            }
        } elseif ($request->filled('action_id') && ! $request->filled('decision_id')) {
            // Allow clearing decision when action changes
            if ($template->isDirty('action_id')) {
                $template->decision_id = null;
            }
        }
        if ($request->has('fail_on_unresolved')) {
            $template->fail_on_unresolved = (bool) $request->boolean('fail_on_unresolved');
        }
        // Build formatting options array from discrete fields if provided
        $fmt = $template->formatting_options ?? [];
        $dirty = false;
        foreach ([
            'number_decimals', 'decimal_separator', 'thousands_separator',
            'currency_symbol', 'currency_position',
        ] as $key) {
            if ($request->filled($key)) {
                $fmt[$key] = $request->input($key);
                $dirty = true;
            } elseif ($request->has($key) && $request->input($key) === null) {
                unset($fmt[$key]);
                $dirty = true;
            }
        }
        if ($request->has('currency_space')) {
            $fmt['currency_space'] = (bool) $request->boolean('currency_space');
            $dirty = true;
        }
        if ($request->filled('default_date_format')) {
            $fmt['default_date_format'] = $request->input('default_date_format');
            $dirty = true;
        }
        if ($request->has('date_formats')) {
            $fmt['date_formats'] = array_filter((array) $request->input('date_formats'), fn ($v) => $v !== null && $v !== '');
            $dirty = true;
        }
        if ($dirty) {
            $template->formatting_options = $fmt;
        }
        // Merge meta, including custom_defaults
        if ($request->has('meta') && is_array($request->input('meta'))) {
            $meta = array_filter($request->input('meta'), fn ($v) => $v !== null && $v !== '');
            $template->meta = array_replace($template->meta ?? [], $meta);
        }
        $template->updated_by = Auth::id();
        $template->save();

        return redirect()->back()->with('success', 'Nastavitve predloge shranjene.');
    }

    public function store(StoreDocumentTemplateRequest $request)
    {
        $this->ensurePermission();
        $file = $request->file('file');

        // Basic extension guard (defense in depth vs only MIME detection)
        if (strtolower($file->getClientOriginalExtension()) !== 'docx') {
            return redirect()->back()->withErrors(['file' => 'Datoteka mora biti DOCX.']);
        }

        $slug = Str::slug($request->slug);

        // Determine next version if slug exists
        $latest = DocumentTemplate::where('slug', $slug)->orderByDesc('version')->first();
        $nextVersion = $latest ? ($latest->version + 1) : 1;

        $hash = hash_file('sha256', $file->getRealPath());
        $path = $file->store("document-templates/{$slug}/v{$nextVersion}", 'public');

        // Scan tokens from uploaded DOCX (best effort)
        $tokens = [];
        try {
            /** @var TokenScanner $scanner */
            $scanner = app(TokenScanner::class);
            $zip = new \ZipArchive;
            $tmp = tempnam(sys_get_temp_dir(), 'tmpl');
            copy($file->getRealPath(), $tmp);
            if ($zip->open($tmp) === true) {
                $xml = $zip->getFromName('word/document.xml');
                if ($xml !== false) {
                    $tokens = $scanner->scan($xml);
                }
                $zip->close();
            }
        } catch (\Throwable $e) {
            // swallow scanning errors
        }

        // (Future) Could refine allowed columns automatically based on tokens
        $entities = ['contract', 'client_case', 'client', 'person', 'account'];
        $columns = [
            'contract' => ['reference', 'start_date', 'end_date', 'description'],
            'client_case' => ['client_ref'],
            'client' => [],
            'person' => ['full_name', 'first_name', 'last_name', 'nu'],
            // Add common account attributes; whitelist may further refine
            'account' => ['reference', 'initial_amount', 'balance_amount', 'promise_date'],
        ];

        $payload = [
            'name' => $request->name,
            'slug' => $slug,
            'custom_name' => $request->custom_name,
            'description' => $request->description,
            'core_entity' => 'contract',
            'entities' => $entities,
            'columns' => $columns,
            'version' => $nextVersion,
            'engine' => 'tokens',
            'file_path' => $path,
            'file_hash' => $hash,
            'file_size' => $file->getSize(),
            'mime_type' => $file->getMimeType(),
            'active' => true,
            'created_by' => $latest ? $latest->created_by : Auth::id(), // preserve original author for lineage if re-upload
            'updated_by' => Auth::id(),
            'formatting_options' => [
                'number_decimals' => 2,
                'decimal_separator' => ',',
                'thousands_separator' => '.',
                'currency_symbol' => '€',
                'currency_position' => 'after',
                'currency_space' => true,
            ],
        ];
        // Optional meta + activity linkage fields (parity with import templates style)
        if ($request->filled('meta') && is_array($request->input('meta'))) {
            $payload['meta'] = array_filter($request->input('meta'), fn ($v) => $v !== null && $v !== '');
        }
        if ($request->filled('action_id')) {
            $payload['action_id'] = $request->integer('action_id');
        }
        if ($request->filled('decision_id')) {
            $payload['decision_id'] = $request->integer('decision_id');
        }
        if ($request->filled('activity_note_template')) {
            $payload['activity_note_template'] = $request->input('activity_note_template');
        }
        if (Schema::hasColumn('document_templates', 'tokens')) {
            $payload['tokens'] = $tokens;
        }
        $template = DocumentTemplate::create($payload);

        return redirect()->back()->with('success', 'Predloga uspešno shranjena. (v'.$template->version.')')->with('template_id', $template->id);
    }

    private function ensurePermission(): void
    {
        if (Gate::denies('manage-document-templates') && Gate::denies('manage-settings')) {
            abort(403);
        }
    }
}