<?php

namespace App\Services;

use App\Models\SocialAutomationSetting;
use App\Models\SocialMediaAsset;
use App\Models\SocialRecurringAlert;
use App\Models\SocialRecurringCampaign;
use App\Models\User;
use Illuminate\Support\Carbon;
use Illuminate\Support\Collection;
use Illuminate\Support\Str;

class SocialRecurringCampaignService
{
    public function __construct(
        private SocialContentGeneratorService $generator,
        private SocialMediaStudioService $studio
    ) {
    }

    public function createFromPayload(User $user, array $data): ?SocialRecurringCampaign
    {
        $frequency = (string) ($data['repeat_frequency'] ?? 'none');
        if ($frequency === 'none') {
            return null;
        }

        $startsAt = Carbon::parse($data['scheduled_at']);
        $endsAt = filled($data['repeat_until'] ?? null)
            ? Carbon::parse((string) $data['repeat_until'])
            : null;
        $nextOccurrenceAt = $this->nextOccurrence($startsAt, $frequency);

        return SocialRecurringCampaign::query()->create([
            'user_id' => $user->id,
            'platforms' => array_values($data['platforms'] ?? []),
            'repeat_frequency' => $frequency,
            'status' => $endsAt && $nextOccurrenceAt->gt($endsAt) ? 'completed' : 'active',
            'brand_label' => $this->normalizeLaneLabel($data['brand_label'] ?? null),
            'team_label' => $this->normalizeLaneLabel($data['team_label'] ?? null),
            'approval_mode' => $this->normalizeApprovalMode($data['approval_mode'] ?? null),
            'title' => $data['title'] ?? null,
            'caption' => (string) ($data['caption'] ?? ''),
            'hashtags' => $this->normalizeHashtags($data['hashtags'] ?? []),
            'image_url' => $data['image_url'] ?? null,
            'video_url' => $data['video_url'] ?? null,
            'starts_at' => $startsAt,
            'next_occurrence_at' => $endsAt && $nextOccurrenceAt->gt($endsAt) ? null : $nextOccurrenceAt,
            'ends_at' => $endsAt,
            'meta' => [
                'bgm' => $this->buildBgmMeta($data),
                'generation' => $this->buildGenerationMeta($data),
            ],
        ]);
    }

    public function enqueueDueCampaigns(int $limit = 30, int $windowMinutes = 60): int
    {
        $processed = 0;
        $horizon = now()->addMinutes(max(1, $windowMinutes));

        $campaigns = SocialRecurringCampaign::query()
            ->where('status', 'active')
            ->whereNotNull('next_occurrence_at')
            ->where('next_occurrence_at', '<=', $horizon)
            ->with('user')
            ->orderBy('next_occurrence_at')
            ->limit(max(1, $limit))
            ->get();

        foreach ($campaigns as $campaign) {
            $occurrenceAt = $campaign->next_occurrence_at;
            if (! $occurrenceAt) {
                continue;
            }

            if ($campaign->ends_at && $occurrenceAt->gt($campaign->ends_at)) {
                $campaign->update([
                    'status' => 'completed',
                    'next_occurrence_at' => null,
                ]);
                continue;
            }

            $alreadyExists = $campaign->user->socialPosts()
                ->where('recurrence_campaign_id', $campaign->id)
                ->where('recurrence_occurrence_at', $occurrenceAt)
                ->exists();

            try {
                if (! $alreadyExists) {
                    $this->enqueueOccurrence($campaign, $occurrenceAt);
                    $processed++;
                }

                $nextOccurrenceAt = $this->nextOccurrence($occurrenceAt, $campaign->repeat_frequency);
                $meta = is_array($campaign->meta) ? $campaign->meta : [];
                unset($meta['last_enqueue_error']);

                $campaign->update([
                    'next_occurrence_at' => $campaign->ends_at && $nextOccurrenceAt->gt($campaign->ends_at)
                        ? null
                        : $nextOccurrenceAt,
                    'status' => $campaign->ends_at && $nextOccurrenceAt->gt($campaign->ends_at)
                        ? 'completed'
                        : 'active',
                    'meta' => $meta,
                ]);

                $this->markFailureAlertsResolved($campaign);
            } catch (\Throwable $e) {
                $meta = is_array($campaign->meta) ? $campaign->meta : [];
                $meta['last_enqueue_error'] = [
                    'message' => $e->getMessage(),
                    'failed_at' => now()->toIso8601String(),
                ];

                $campaign->update([
                    'meta' => $meta,
                ]);

                $this->createFailureAlert($campaign, $occurrenceAt, $e);
            }
        }

        return $processed;
    }

    public function pause(SocialRecurringCampaign $campaign): void
    {
        $campaign->update([
            'status' => 'paused',
        ]);
    }

    public function resume(SocialRecurringCampaign $campaign): void
    {
        $nextOccurrenceAt = $campaign->next_occurrence_at ?: $this->nextOccurrence(
            $campaign->starts_at ?: now(),
            $campaign->repeat_frequency
        );

        if ($campaign->ends_at && $nextOccurrenceAt->gt($campaign->ends_at)) {
            $campaign->update([
                'status' => 'completed',
                'next_occurrence_at' => null,
            ]);

            return;
        }

        $campaign->update([
            'status' => 'active',
            'next_occurrence_at' => $nextOccurrenceAt,
        ]);
    }

    public function updateCampaign(SocialRecurringCampaign $campaign, array $data): void
    {
        $meta = is_array($campaign->meta) ? $campaign->meta : [];
        $meta['bgm'] = $this->buildBgmMeta($data);
        $meta['generation'] = $this->buildGenerationMeta($data);

        $nextOccurrenceAt = Carbon::parse($data['next_occurrence_at']);
        $endsAt = filled($data['repeat_until'] ?? null)
            ? Carbon::parse((string) $data['repeat_until'])
            : null;

        $status = $campaign->status === 'completed' ? 'active' : $campaign->status;

        if ($endsAt && $nextOccurrenceAt->gt($endsAt)) {
            $status = 'completed';
            $nextOccurrenceAt = null;
        }

        $campaign->update([
            'platforms' => array_values($data['platforms'] ?? []),
            'repeat_frequency' => $data['repeat_frequency'],
            'status' => $status,
            'brand_label' => $this->normalizeLaneLabel($data['brand_label'] ?? null),
            'team_label' => $this->normalizeLaneLabel($data['team_label'] ?? null),
            'approval_mode' => $this->normalizeApprovalMode($data['approval_mode'] ?? null),
            'title' => $data['title'] ?? null,
            'caption' => (string) $data['caption'],
            'hashtags' => $this->normalizeHashtags($data['hashtags'] ?? []),
            'image_url' => $data['image_url'] ?? null,
            'video_url' => $data['video_url'] ?? null,
            'starts_at' => Carbon::parse($data['starts_at']),
            'next_occurrence_at' => $nextOccurrenceAt,
            'ends_at' => $endsAt,
            'meta' => $meta,
        ]);
    }

    public function enqueueCampaignNow(SocialRecurringCampaign $campaign): void
    {
        $scheduledAt = now()->startOfMinute();

        $this->enqueueOccurrence($campaign, $scheduledAt);
    }

    public function nextOccurrence(Carbon $from, string $frequency): Carbon
    {
        return match ($frequency) {
            'daily' => $from->copy()->addDay(),
            'weekly' => $from->copy()->addWeek(),
            default => $from->copy(),
        };
    }

    private function enqueueOccurrence(SocialRecurringCampaign $campaign, Carbon $scheduledAt): void
    {
        $setting = $this->settingFor($campaign->user_id);
        $bgmMeta = is_array($campaign->meta) ? (array) ($campaign->meta['bgm'] ?? []) : [];
        $payload = $this->buildOccurrencePayload($campaign);
        $approvalMode = $this->resolveApprovalMode($campaign, $setting);
        $recurringContext = [
            'brand_label' => $campaign->brand_label,
            'team_label' => $campaign->team_label,
            'approval_mode' => $approvalMode,
        ];

        foreach ((array) ($campaign->platforms ?? []) as $platform) {
            $requiresApproval = $approvalMode === 'manual';
            $status = $requiresApproval ? 'draft' : 'scheduled';

            $campaign->user->socialPosts()->create([
                'platform' => $platform,
                'status' => $status,
                'requires_approval' => $requiresApproval,
                'title' => $payload['title'],
                'caption' => $payload['caption'],
                'hashtags' => $payload['hashtags'],
                'image_url' => $payload['image_url'],
                'video_url' => $payload['video_url'],
                'scheduled_at' => $scheduledAt,
                'approved_at' => $requiresApproval ? null : now(),
                'meta' => [
                    'bgm' => $bgmMeta,
                    'recurring_context' => $recurringContext,
                ],
                'recurrence_campaign_id' => $campaign->id,
                'recurrence_occurrence_at' => $scheduledAt,
            ]);
        }
    }

    private function buildOccurrencePayload(SocialRecurringCampaign $campaign): array
    {
        $generation = is_array($campaign->meta) ? (array) ($campaign->meta['generation'] ?? []) : [];

        $title = (string) ($campaign->title ?? '');
        $caption = (string) ($campaign->caption ?? '');
        $hashtags = is_array($campaign->hashtags) ? $campaign->hashtags : [];
        $imageUrl = $campaign->image_url;
        $videoUrl = $campaign->video_url;

        if (($generation['regenerate_content'] ?? false) && filled($generation['topic'] ?? null)) {
            $generated = $this->generator->generate(
                (string) $generation['topic'],
                (string) ($generation['platform_hint'] ?? implode(', ', (array) ($campaign->platforms ?? []))),
                (string) ($generation['tone'] ?? 'friendly-professional')
            );

            $title = trim((string) ($generated['title'] ?? $title));
            $caption = $this->composeGeneratedCaption($generated);
            $hashtags = $this->normalizeHashtags($generated['hashtags'] ?? []);
        }

        if (($generation['regenerate_media'] ?? false) && ($generation['auto_generate_image'] ?? false)) {
            $imagePrompt = $this->resolveAutoMediaPrompt(
                (string) ($generation['image_prompt'] ?? ''),
                $title,
                $caption,
                'image'
            );
            $imageMedia = $this->studio->generateImage($imagePrompt);
            $imageUrl = $this->persistGeneratedImage($campaign->user_id, $imageMedia);
        }

        if (($generation['regenerate_media'] ?? false) && ($generation['auto_generate_video'] ?? false)) {
            $videoPrompt = $this->resolveAutoMediaPrompt(
                (string) ($generation['video_prompt'] ?? ''),
                $title,
                $caption,
                'video'
            );
            $videoMedia = $this->studio->generateVideo($videoPrompt);
            $videoUrl = $this->persistGeneratedVideo($campaign->user_id, $videoMedia);
        }

        return [
            'title' => $title !== '' ? $title : null,
            'caption' => $caption,
            'hashtags' => $hashtags,
            'image_url' => $imageUrl,
            'video_url' => $videoUrl,
        ];
    }

    private function settingFor(int $userId): SocialAutomationSetting
    {
        return SocialAutomationSetting::query()->firstOrCreate(
            ['user_id' => $userId],
            [
                'approval_mode' => 'manual',
                'daily_limit' => 20,
                'platform_daily_limits' => [
                    'facebook' => 8,
                    'instagram' => 8,
                    'tiktok' => 4,
                    'x' => 12,
                ],
                'max_retries' => 2,
                'retry_delay_minutes' => 15,
            ]
        );
    }

    private function normalizeHashtags(array|string|null $hashtags): array
    {
        $items = is_array($hashtags) ? $hashtags : explode(',', (string) $hashtags);

        return collect($items)
            ->map(fn ($item) => trim((string) $item))
            ->filter()
            ->map(fn ($item) => ltrim($item, '#'))
            ->values()
            ->all();
    }

    private function buildBgmMeta(array $data): array
    {
        return [
            'enabled' => ($data['bgm_auto'] ?? '1') === '1',
            'provider' => 'freepik',
            'prompt' => trim((string) ($data['bgm_prompt'] ?? '')),
            'duration' => (int) ($data['bgm_duration'] ?? 15),
            'volume' => (float) ($data['bgm_volume'] ?? 0.24),
            'applied' => false,
        ];
    }

    private function buildGenerationMeta(array $data): array
    {
        return [
            'topic' => trim((string) ($data['topic'] ?? '')),
            'tone' => trim((string) ($data['tone'] ?? 'friendly-professional')),
            'platform_hint' => trim((string) ($data['platform_hint'] ?? implode(', ', (array) ($data['platforms'] ?? [])))),
            'regenerate_content' => ($data['repeat_refresh_content'] ?? '0') === '1',
            'regenerate_media' => ($data['repeat_refresh_media'] ?? '0') === '1',
            'auto_generate_image' => ($data['auto_generate_image'] ?? '0') === '1',
            'auto_generate_video' => ($data['auto_generate_video'] ?? '0') === '1',
            'image_prompt' => trim((string) ($data['image_prompt'] ?? '')),
            'video_prompt' => trim((string) ($data['video_prompt'] ?? '')),
        ];
    }

    private function composeGeneratedCaption(array $generated): string
    {
        $caption = trim((string) ($generated['caption'] ?? ''));
        $cta = trim((string) ($generated['cta'] ?? ''));

        if ($caption === '') {
            return $cta;
        }

        if ($cta === '' || str_contains(mb_strtolower($caption), mb_strtolower($cta))) {
            return $caption;
        }

        return trim($caption."\n\n".$cta);
    }

    private function resolveAutoMediaPrompt(string $customPrompt, string $title, string $caption, string $type): string
    {
        $customPrompt = trim($customPrompt);
        if ($customPrompt !== '') {
            return $customPrompt;
        }

        if ($type === 'video') {
            return trim($title.'. '.$caption.' Vertical social video 9:16, premium campaign motion, clean branding, engaging movement.');
        }

        return trim($title.'. '.$caption.' Vertical social image 9:16, premium campaign visual, clean branding, modern healthcare technology.');
    }

    private function persistGeneratedImage(int $userId, array $media): ?string
    {
        $variants = collect($media['variants'] ?? [])
            ->filter(fn ($item) => is_array($item) && filled($item['url'] ?? null))
            ->values();

        if ($variants->isEmpty() && filled($media['url'] ?? null)) {
            $variants = collect([[
                'url' => (string) $media['url'],
                'thumbnail_url' => (string) ($media['thumbnail_url'] ?? $media['url']),
                'width' => (int) ($media['width'] ?? 1080),
                'height' => (int) ($media['height'] ?? 1920),
            ]]);
        }

        /** @var Collection<int, array> $variants */
        return $variants->map(function (array $variant) use ($userId, $media) {
            $asset = SocialMediaAsset::query()->create([
                'user_id' => $userId,
                'type' => 'image',
                'provider' => (string) ($media['provider'] ?? 'unknown'),
                'prompt' => (string) ($media['prompt'] ?? ''),
                'url' => (string) $variant['url'],
                'thumbnail_url' => (string) ($variant['thumbnail_url'] ?? $variant['url']),
                'width' => (int) ($variant['width'] ?? $media['width'] ?? 1080),
                'height' => (int) ($variant['height'] ?? $media['height'] ?? 1920),
                'meta' => [
                    'aspect' => $media['aspect'] ?? '9:16',
                    'source' => 'recurring_campaign',
                ],
            ]);

            return (string) $asset->url;
        })->first();
    }

    private function persistGeneratedVideo(int $userId, array $media): ?string
    {
        $url = (string) ($media['url'] ?? '');
        if ($url === '') {
            return null;
        }

        $asset = SocialMediaAsset::query()->create([
            'user_id' => $userId,
            'type' => 'video',
            'provider' => (string) ($media['provider'] ?? 'unknown'),
            'prompt' => (string) ($media['prompt'] ?? ''),
            'url' => $url,
            'thumbnail_url' => (string) ($media['source_image_url'] ?? ''),
            'width' => 1080,
            'height' => 1920,
            'duration_seconds' => (int) ($media['duration_seconds'] ?? 0),
            'meta' => [
                'aspect' => $media['aspect'] ?? '9:16',
                'source_image_provider' => $media['source_image_provider'] ?? null,
                'source' => 'recurring_campaign',
            ],
        ]);

        return (string) $asset->url;
    }

    private function resolveApprovalMode(SocialRecurringCampaign $campaign, SocialAutomationSetting $setting): string
    {
        $campaignMode = $this->normalizeApprovalMode($campaign->approval_mode);

        return $campaignMode === 'inherit'
            ? $setting->approval_mode
            : $campaignMode;
    }

    private function normalizeApprovalMode(?string $approvalMode): string
    {
        $approvalMode = trim((string) $approvalMode);

        return in_array($approvalMode, ['inherit', 'manual', 'auto'], true)
            ? $approvalMode
            : 'inherit';
    }

    private function normalizeLaneLabel(?string $value): ?string
    {
        $value = trim((string) $value);

        return $value !== '' ? Str::limit($value, 120, '') : null;
    }

    private function createFailureAlert(SocialRecurringCampaign $campaign, Carbon $occurrenceAt, \Throwable $e): void
    {
        $message = trim($e->getMessage());
        if ($message === '') {
            $message = 'Unknown recurring campaign failure.';
        }

        $duplicateExists = SocialRecurringAlert::query()
            ->where('user_id', $campaign->user_id)
            ->where('social_recurring_campaign_id', $campaign->id)
            ->where('type', 'enqueue_failed')
            ->whereNull('read_at')
            ->where('message', $message)
            ->where('created_at', '>=', now()->subHours(6))
            ->exists();

        if ($duplicateExists) {
            return;
        }

        SocialRecurringAlert::query()->create([
            'user_id' => $campaign->user_id,
            'social_recurring_campaign_id' => $campaign->id,
            'type' => 'enqueue_failed',
            'title' => 'Recurring enqueue failed',
            'message' => $message,
            'context' => [
                'campaign_id' => $campaign->id,
                'campaign_title' => $campaign->title,
                'platforms' => $campaign->platforms,
                'brand_label' => $campaign->brand_label,
                'team_label' => $campaign->team_label,
                'occurrence_at' => $occurrenceAt->toIso8601String(),
            ],
        ]);
    }

    private function markFailureAlertsResolved(SocialRecurringCampaign $campaign): void
    {
        SocialRecurringAlert::query()
            ->where('user_id', $campaign->user_id)
            ->where('social_recurring_campaign_id', $campaign->id)
            ->where('type', 'enqueue_failed')
            ->whereNull('read_at')
            ->update([
                'read_at' => now(),
            ]);
    }
}