(function (root, factory) {
    const service = factory();
    if (typeof module === 'object' && module.exports) module.exports = service;
    if (root) root.LiveChannelProjection = service;
})(typeof globalThis !== 'undefined' ? globalThis : this, function () {
    function normalizeSearch(value) {
        return String(value || '')
            .normalize('NFKD').replace(/[\u0300-\u036f]/g, '')
            .toLowerCase().replace(/[^a-z0-9]+/g, ' ').trim()
            .split(/\s+/).filter(Boolean)
            .map(token => token.length > 3 && token.endsWith('s') ? token.slice(0, -1) : token);
    }

    function matchesSearch(channel, query) {
        const wanted = normalizeSearch(query);
        if (!wanted.length) return true;
        const corpus = normalizeSearch([
            channel.displayName, channel.standardName, channel.fingerprint,
            ...(channel.variants || []).flatMap(variant => [
                variant.name, variant.tvgId, variant.categoryName, variant.groupTitle
            ])
        ].filter(Boolean).join(' '));
        return wanted.every(token => corpus.some(candidate => candidate.includes(token)));
    }

    function normalizeLanguage(language) {
        const rawCode = typeof language?.code === 'string' ? language.code.trim().toLowerCase() : '';
        const code = rawCode || 'und';
        const confidence = Number(language?.confidence);
        return {
            code,
            short: language?.short || (code === 'und' ? 'UND' : code.toUpperCase()),
            label: language?.label || (code === 'und' ? 'Unknown' : code.toUpperCase()),
            confidence: Number.isFinite(confidence) ? confidence : 0
        };
    }

    function mapResponse(response, sources = []) {
        if (!response || !Array.isArray(response.channels)) {
            throw new Error('Invalid live channel projection response');
        }

        const sourceById = new Map(sources.map(source => [String(source.id), source]));
        const favorites = new Set();
        const hiddenItems = new Set();
        const channels = [];
        const logicalChannels = [];
        const hasLanguageViews = response.channels.every(channel => channel?.logicalChannelId);

        response.channels.forEach(logicalChannel => {
            if (!logicalChannel) return;
            const rawVariants = Array.isArray(logicalChannel.variants)
                ? logicalChannel.variants.filter(Boolean)
                : (logicalChannel.preferredVariant ? [logicalChannel.preferredVariant] : []);
            const mappedVariants = [];
            rawVariants.forEach(variant => {
                const source = sourceById.get(String(variant.sourceId));
                const id = String(variant.id);
                const mapped = {
                    ...variant,
                    id,
                    logicalId: logicalChannel.id,
                    logicalFingerprint: logicalChannel.fingerprint || logicalChannel.id,
                    logicalDisplayName: logicalChannel.displayName || logicalChannel.name,
                    streamId: variant.streamId ?? id,
                    tvgId: variant.tvgId ?? variant.epg_channel_id ?? null,
                    tvgLogo: variant.tvgLogo ?? variant.streamIcon ?? variant.stream_icon ?? '',
                    url: variant.url ?? variant.streamUrl ?? variant.stream_url ?? '',
                    groupTitle: variant.groupTitle ?? variant.categoryName ?? variant.categoryId ?? 'Uncategorized',
                    sourceType: variant.sourceType ?? source?.type ?? 'xtream',
                    sourceName: variant.sourceName ?? source?.name ?? ''
                };
                mapped.language = normalizeLanguage(variant.language || logicalChannel.language);
                channels.push(mapped);
                mappedVariants.push(mapped);
                const key = `${mapped.sourceId}:${id}`;
                if (variant.isFavorite) favorites.add(key);
                if (variant.isHidden) hiddenItems.add(`channel:${mapped.sourceId}:${mapped.streamId || id}`);
            });
            if (!mappedVariants.length) return;
            const preferredVariant = mappedVariants.find(variant =>
                `${variant.sourceId}:${variant.id}` === String(logicalChannel.selectedVariantId)
            ) || mappedVariants.find(variant => String(variant.id) === String(logicalChannel.preferredVariant?.id))
                || mappedVariants[0];
            const language = normalizeLanguage(logicalChannel.language || preferredVariant.language);
            if (hasLanguageViews) logicalChannels.push({
                ...logicalChannel,
                fingerprint: logicalChannel.id,
                displayName: logicalChannel.displayName || logicalChannel.standardName || logicalChannel.name,
                name: logicalChannel.displayName || logicalChannel.standardName || logicalChannel.name,
                variants: mappedVariants,
                visibleVariants: mappedVariants.filter(variant => !variant.isHidden),
                preferredVariant,
                language,
                selectedVariantId: `${preferredVariant.sourceId}:${preferredVariant.id}`,
                groupTitle: preferredVariant.groupTitle,
                tvgLogo: preferredVariant.tvgLogo,
                tvgId: logicalChannel.epg?.channelId || preferredVariant.tvgId,
                isFavorite: mappedVariants.some(variant => variant.isFavorite),
                isHidden: mappedVariants.every(variant => variant.isHidden)
            });
        });

        return {
            channels, logicalChannels: hasLanguageViews ? logicalChannels : null, favorites, hiddenItems,
            availableLanguages: (response.filters?.availableLanguages || []).filter(Boolean).map(normalizeLanguage),
            projection: response.projection || {}
        };
    }

    function canUse(response) {
        if (!response || !Array.isArray(response.channels) || response.projection?.stale) return false;

        const projection = response.projection || {};
        const expectedChannelCount = [
            projection.total,
            projection.processed,
            projection.catalogCount,
            projection.sourceChannelCount
        ].some(count => Number(count) > 0);

        return response.channels.length > 0 || !expectedChannelCount;
    }

    return { canUse, mapResponse, matchesSearch, normalizeLanguage, normalizeSearch };
});