/**
 * Search utilities for OpenPrompt
 * Supports full-text search across prompts
 */

export interface SearchFilters {
    query?: string
    category?: string
    tags?: string[]
    model?: string
    minStars?: number
    minRuns?: number
    dateRange?: 'day' | 'week' | 'month' | 'all'
    sortBy?: 'trending' | 'recent' | 'stars' | 'runs'
}

export interface SearchResult {
    id: string
    slug: string
    title: string
    description: string | null
    category: string | null
    tags: string[]
    totalRuns: number
    starsCount: number
    remixesCount: number
    createdAt: Date
    creator: {
        name: string | null
        username: string | null
        image: string | null
    } | null
    score?: number // relevance score
}

/**
 * Build Prisma where clause from search filters
 */
export function buildSearchWhere(filters: SearchFilters) {
    const where: Record<string, unknown> = {
        visibility: 'public',
    }

    // Text search (title + description)
    if (filters.query) {
        where.OR = [
            { title: { contains: filters.query, mode: 'insensitive' } },
            { description: { contains: filters.query, mode: 'insensitive' } },
            { tags: { hasSome: [filters.query.toLowerCase()] } },
        ]
    }

    // Category filter
    if (filters.category) {
        where.category = filters.category
    }

    // Tags filter
    if (filters.tags && filters.tags.length > 0) {
        where.tags = { hasSome: filters.tags }
    }

    // Model filter
    if (filters.model) {
        where.modelAllowed = { has: filters.model }
    }

    // Stars filter
    if (filters.minStars) {
        where.starsCount = { gte: filters.minStars }
    }

    // Runs filter
    if (filters.minRuns) {
        where.totalRuns = { gte: filters.minRuns }
    }

    // Date range filter
    if (filters.dateRange && filters.dateRange !== 'all') {
        const now = new Date()
        const cutoff = new Date()

        switch (filters.dateRange) {
            case 'day':
                cutoff.setDate(now.getDate() - 1)
                break
            case 'week':
                cutoff.setDate(now.getDate() - 7)
                break
            case 'month':
                cutoff.setMonth(now.getMonth() - 1)
                break
        }

        where.createdAt = { gte: cutoff }
    }

    return where
}

/**
 * Build Prisma orderBy from sort option
 */
export function buildSearchOrderBy(sortBy: SearchFilters['sortBy'] = 'trending') {
    switch (sortBy) {
        case 'recent':
            return [{ createdAt: 'desc' as const }]
        case 'stars':
            return [{ starsCount: 'desc' as const }, { createdAt: 'desc' as const }]
        case 'runs':
            return [{ totalRuns: 'desc' as const }, { createdAt: 'desc' as const }]
        case 'trending':
        default:
            // Trending uses a calculated score (handled separately)
            return [{ totalRuns: 'desc' as const }, { starsCount: 'desc' as const }]
    }
}

/**
 * Extract unique categories from prompts
 */
export function getCategories(): string[] {
    return [
        'Content',
        'Development',
        'Marketing',
        'Business',
        'Education',
        'Creative',
        'Research',
    ]
}

/**
 * Extract unique tags from prompts
 */
export async function getPopularTags(limit: number = 20): Promise<string[]> {
    try {
        // Query database for actual popular tags
        const { prisma } = await import('@/lib/prisma')
        const prompts = await prisma.prompt.findMany({
            where: { visibility: 'public', tags: { isEmpty: false } },
            select: { tags: true },
            orderBy: { totalRuns: 'desc' },
            take: 200,
        })

        // Count tag frequency
        const tagCounts = new Map<string, number>()
        for (const prompt of prompts) {
            for (const tag of prompt.tags) {
                tagCounts.set(tag, (tagCounts.get(tag) || 0) + 1)
            }
        }

        // Sort by frequency and return top N
        return [...tagCounts.entries()]
            .sort((a, b) => b[1] - a[1])
            .slice(0, limit)
            .map(([tag]) => tag)
    } catch {
        // Fallback to hardcoded list if DB query fails
        return [
            'blog', 'writing', 'code', 'email', 'social-media',
            'seo', 'ai', 'productivity', 'marketing', 'business',
        ].slice(0, limit)
    }
}