<?php

namespace App\Services\Meet;

use App\Models\AiSummary;
use App\Models\Transcript;
use App\Models\ActionItem;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Str;
use RuntimeException;

class MeetAiService
{
    public function enabled(): bool
    {
        return (bool) config('meet.ai.enabled', true)
            && ((string) config('meet.ai.api_key') !== '' || $this->hasPlatformRelay());
    }

    public function summarize(Transcript $transcript): AiSummary
    {
        $summary = AiSummary::create([
            'owner_ref' => $transcript->owner_ref,
            'session_id' => $transcript->session_id,
            'transcript_id' => $transcript->id,
            'status' => 'processing',
        ]);

        try {
            $result = $this->generateSummary((string) $transcript->content);
            $summary->update([
                'status' => 'ready',
                'summary' => $result['summary'] ?? '',
                'decisions' => $result['decisions'] ?? [],
            ]);

            foreach ($result['action_items'] ?? [] as $item) {
                ActionItem::create([
                    'owner_ref' => $transcript->owner_ref,
                    'ai_summary_id' => $summary->id,
                    'assignee_name' => $item['assignee'] ?? null,
                    'description' => $item['description'] ?? '',
                    'due_date' => $item['due_date'] ?? null,
                    'status' => 'open',
                ]);
            }
        } catch (\Throwable $e) {
            report($e);
            $summary->update(['status' => 'failed', 'summary' => 'AI summary could not be generated.']);
        }

        app(MeetNotificationService::class)->aiSummaryReady($summary->fresh());

        return $summary->fresh();
    }

    /**
     * @return array{summary: string, decisions: array, action_items: array}
     */
    protected function generateSummary(string $transcript): array
    {
        if (! $this->enabled()) {
            return $this->stubSummary($transcript);
        }

        $prompt = <<<PROMPT
Analyze this meeting transcript and respond in JSON with keys:
- summary (string, 2-4 paragraphs)
- decisions (array of strings)
- action_items (array of {assignee, description, due_date or null})

Transcript:
{$transcript}
PROMPT;

        $reply = $this->hasLocalKey()
            ? $this->viaOpenAi($prompt)
            : $this->viaPlatform($prompt);

        $parsed = json_decode($reply, true);
        if (! is_array($parsed)) {
            return ['summary' => $reply, 'decisions' => [], 'action_items' => []];
        }

        return $parsed;
    }

    protected function stubSummary(string $transcript): array
    {
        $preview = Str::limit($transcript, 500);

        return [
            'summary' => "Meeting summary (AI not configured).\n\nTranscript preview:\n".$preview,
            'decisions' => [],
            'action_items' => [],
        ];
    }

    protected function viaOpenAi(string $prompt): string
    {
        $res = Http::withToken((string) config('meet.ai.api_key'))->acceptJson()->timeout(60)
            ->post('https://api.openai.com/v1/chat/completions', [
                'model' => config('meet.ai.model', 'gpt-4o-mini'),
                'temperature' => 0.2,
                'response_format' => ['type' => 'json_object'],
                'messages' => [
                    ['role' => 'system', 'content' => 'You summarize Ladill Meet transcripts. Return valid JSON only.'],
                    ['role' => 'user', 'content' => $prompt],
                ],
            ]);

        if ($res->failed()) {
            throw new RuntimeException('OpenAI request failed: '.$res->status());
        }

        return trim((string) $res->json('choices.0.message.content', ''));
    }

    protected function viaPlatform(string $prompt): string
    {
        $base = rtrim((string) config('meet.ai.platform_api_url'), '/');
        $res = Http::withToken((string) config('meet.ai.platform_api_key'))->acceptJson()->timeout(60)
            ->post($base.'/afia/chat', [
                'product' => 'meet',
                'message' => $prompt,
                'history' => [],
                'system_prompt' => 'You summarize Ladill Meet transcripts. Return valid JSON only.',
            ]);

        if ($res->failed()) {
            throw new RuntimeException('Platform AI relay failed.');
        }

        return trim((string) $res->json('reply', ''));
    }

    protected function hasLocalKey(): bool
    {
        return (string) config('meet.ai.api_key') !== '';
    }

    protected function hasPlatformRelay(): bool
    {
        return rtrim((string) config('meet.ai.platform_api_url'), '/') !== ''
            && (string) config('meet.ai.platform_api_key') !== '';
    }
}