<?php

namespace App\Services\Fox;

use App\Models\Fox\FoxLearningEvent;
use App\Models\Fox\FoxMemoryEdge;
use App\Models\Fox\FoxMemoryNode;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;

class FoxMemoryService
{
    public function createNode(array $data): FoxMemoryNode
    {
        return FoxMemoryNode::create([
            'type'       => $data['type'] ?? 'fact',
            'title'      => $data['title'],
            'content'    => $data['content'] ?? null,
            'meta'       => $data['meta'] ?? null,
            'confidence' => $data['confidence'] ?? 1.0,
            'weight'     => $data['weight'] ?? 1,
        ]);
    }

    public function updateNode(FoxMemoryNode $node, array $data): FoxMemoryNode
    {
        $node->update(array_filter([
            'type'       => $data['type'] ?? null,
            'title'      => $data['title'] ?? null,
            'content'    => $data['content'] ?? null,
            'meta'       => $data['meta'] ?? null,
            'confidence' => $data['confidence'] ?? null,
            'weight'     => $data['weight'] ?? null,
        ], fn ($v) => $v !== null));

        return $node->fresh();
    }

    public function createEdge(
        FoxMemoryNode $source,
        FoxMemoryNode $target,
        string $relation,
        float $strength = 1.0,
        array $meta = [],
    ): FoxMemoryEdge {
        return FoxMemoryEdge::create([
            'source_node_id' => $source->id,
            'target_node_id' => $target->id,
            'relation'       => $relation,
            'strength'       => $strength,
            'meta'           => empty($meta) ? null : $meta,
        ]);
    }

    public function storeLearningEvent(
        string $input,
        array $extractedMemory = [],
        string $status = FoxLearningEvent::STATUS_PENDING,
    ): FoxLearningEvent {
        return FoxLearningEvent::create([
            'input'            => $input,
            'extracted_memory' => empty($extractedMemory) ? null : $extractedMemory,
            'status'           => $status,
        ]);
    }

    public function approveLearningEvent(FoxLearningEvent $event): void
    {
        $event->update([
            'status'      => FoxLearningEvent::STATUS_APPROVED,
            'approved_at' => now(),
        ]);

        $memory = $event->extracted_memory ?? [];
        if (empty($memory)) {
            return;
        }

        DB::transaction(function () use ($memory) {
            foreach ($memory['nodes'] ?? [] as $nodeData) {
                $existing = FoxMemoryNode::where('title', $nodeData['title'])
                    ->where('type', $nodeData['type'] ?? 'fact')
                    ->first();

                if ($existing) {
                    $this->updateNode($existing, $nodeData);
                } else {
                    $this->createNode($nodeData);
                }
            }

            foreach ($memory['edges'] ?? [] as $edgeData) {
                $source = FoxMemoryNode::where('title', $edgeData['source'])->first();
                $target = FoxMemoryNode::where('title', $edgeData['target'])->first();

                if ($source && $target) {
                    $exists = FoxMemoryEdge::where('source_node_id', $source->id)
                        ->where('target_node_id', $target->id)
                        ->where('relation', $edgeData['relation'])
                        ->exists();

                    if (! $exists) {
                        $this->createEdge(
                            $source,
                            $target,
                            $edgeData['relation'],
                            (float) ($edgeData['strength'] ?? 1.0),
                        );
                    }
                }
            }
        });
    }

    public function rejectLearningEvent(FoxLearningEvent $event): void
    {
        $event->update([
            'status'      => FoxLearningEvent::STATUS_REJECTED,
            'rejected_at' => now(),
        ]);
    }

    /**
     * Simple relevance search via title/content LIKE match.
     * Structure ready for vector embeddings later — swap this method body.
     */
    public function searchRelevantMemories(string $query, int $limit = 10): Collection
    {
        if (blank($query)) {
            return collect();
        }

        $terms = collect(explode(' ', $query))
            ->filter(fn ($t) => mb_strlen($t) > 2)
            ->take(5);

        $q = FoxMemoryNode::query();

        foreach ($terms as $term) {
            $q->orWhere('title', 'ilike', "%{$term}%")
              ->orWhere('content', 'ilike', "%{$term}%")
              ->orWhere('type', 'ilike', "%{$term}%");
        }

        $results = $q->orderByDesc('weight')
            ->orderByDesc('confidence')
            ->limit($limit)
            ->get();

        $results->each(fn (FoxMemoryNode $n) => $n->touchUsed());

        return $results;
    }

    public function buildGraphPayload(): array
    {
        $nodes = FoxMemoryNode::orderByDesc('weight')->get();
        $edges = FoxMemoryEdge::all();

        $typeColors = [
            'user'       => '#22d3ee',
            'project'    => '#818cf8',
            'place'      => '#f59e0b',
            'device'     => '#34d399',
            'skill'      => '#a78bfa',
            'preference' => '#fb7185',
            'fact'       => '#ffffff',
        ];

        return [
            'nodes' => $nodes->map(fn (FoxMemoryNode $n) => [
                'id'         => $n->id,
                'label'      => $n->title,
                'type'       => $n->type,
                'color'      => $typeColors[$n->type] ?? '#818cf8',
                'content'    => $n->content,
                'weight'     => $n->weight,
                'confidence' => $n->confidence,
            ])->values()->all(),

            'edges' => $edges->map(fn (FoxMemoryEdge $e) => [
                'id'       => $e->id,
                'source'   => $e->source_node_id,
                'target'   => $e->target_node_id,
                'relation' => $e->relation,
                'strength' => $e->strength,
            ])->values()->all(),
        ];
    }

    public function stats(): array
    {
        return [
            'nodes_count'   => FoxMemoryNode::count(),
            'edges_count'   => FoxMemoryEdge::count(),
            'pending_count' => FoxLearningEvent::pending()->count(),
        ];
    }
}