src/lib/seo.ts

export interface SEOConfig {
    title: string
    description: string
    keywords?: string[]
    image?: string
    url?: string
    type?: 'website' | 'article' | 'profile'
    publishedTime?: string
    modifiedTime?: string
    author?: string
    section?: string
}

const BASE_URL = process.env.NEXT_PUBLIC_APP_URL || 'https://open-prompt.netlify.app'

// Use dynamic OG route as default (no static og-image.png needed)
const DEFAULT_IMAGE = `${BASE_URL}/api/og?title=OpenPrompt&description=The+GitHub+for+AI+Prompts`

/**
 * Generate a dynamic OG image URL via /api/og
 */
export function generateOGImageUrl(params: {
    title: string
    description?: string
    type?: 'default' | 'prompt' | 'tool' | 'creator' | 'collection'
    category?: string
    runs?: number
    stars?: number
    remixes?: number
    creator?: string
    badge?: string
}): string {
    const url = new URL(`${BASE_URL}/api/og`)
    url.searchParams.set('title', params.title.slice(0, 80))
    if (params.description) url.searchParams.set('description', params.description.slice(0, 140))
    if (params.type) url.searchParams.set('type', params.type)
    if (params.category) url.searchParams.set('category', params.category)
    if (params.runs !== undefined) url.searchParams.set('runs', formatCount(params.runs))
    if (params.stars !== undefined) url.searchParams.set('stars', formatCount(params.stars))
    if (params.remixes !== undefined) url.searchParams.set('remixes', formatCount(params.remixes))
    if (params.creator) url.searchParams.set('creator', params.creator)
    if (params.badge) url.searchParams.set('badge', params.badge)
    return url.toString()
}

function formatCount(n: number): string {
    if (n >= 1_000_000) return (n / 1_000_000).toFixed(1).replace(/\.0$/, '') + 'M'
    if (n >= 1_000) return (n / 1_000).toFixed(1).replace(/\.0$/, '') + 'K'
    return n.toString()
}

export function generateSEO(config: SEOConfig) {
    const {
        title,
        description,
        keywords = [],
        image = DEFAULT_IMAGE,
        url = BASE_URL,
        type = 'website',
        publishedTime,
        modifiedTime,
        author,
        section,
    } = config

    const fullTitle = title.includes('OpenPrompt') ? title : `${title} | OpenPrompt`

    return {
        title: fullTitle,
        description,
        keywords: [
            'AI prompts',
            'prompt engineering',
            'ChatGPT prompts',
            'Claude prompts',
            'AI tools',
            'prompt marketplace',
            ...keywords,
        ],
        authors: [{ name: author || 'OpenPrompt', url: 'https://github.com/Anky9972' }],
        creator: 'OpenPrompt',
        publisher: 'OpenPrompt',
        metadataBase: new URL(BASE_URL),
        alternates: {
            canonical: url,
        },
        openGraph: {
            title: fullTitle,
            description,
            url,
            siteName: 'OpenPrompt',
            images: [
                {
                    url: image,
                    width: 1200,
                    height: 630,
                    alt: title,
                },
            ],
            locale: 'en_US',
            type,
            ...(publishedTime && { publishedTime }),
            ...(modifiedTime && { modifiedTime }),
            ...(section && { section }),
        },
        twitter: {
            card: 'summary_large_image',
            title: fullTitle,
            description,
            images: [image],
            creator: '@anky_vivek',
            site: '@openprompt',
        },
        robots: {
            index: true,
            follow: true,
            googleBot: {
                index: true,
                follow: true,
                'max-video-preview': -1,
                'max-image-preview': 'large',
                'max-snippet': -1,
            },
        },
        verification: {
            google: 'google60f35921954050fd',
        },
    }
}

// JSON-LD Structured Data generators
export function generateWebsiteSchema() {
    return {
        '@context': 'https://schema.org',
        '@type': 'WebSite',
        name: 'OpenPrompt',
        description: 'The GitHub for AI Prompts - Transform AI prompts into shareable micro-apps',
        url: BASE_URL,
        potentialAction: {
            '@type': 'SearchAction',
            target: {
                '@type': 'EntryPoint',
                urlTemplate: `${BASE_URL}/explore?q={search_term_string}`,
            },
            'query-input': 'required name=search_term_string',
        },
        sameAs: [
            'https://github.com/Anky9972/open-prompt',
            'https://twitter.com/anky_vivek',
        ],
    }
}

export function generateOrganizationSchema() {
    return {
        '@context': 'https://schema.org',
        '@type': 'Organization',
        name: 'OpenPrompt',
        url: BASE_URL,
        logo: `${BASE_URL}/logos/logo.svg`,
        description: 'The GitHub for AI Prompts - Transform AI prompts into shareable micro-apps',
        sameAs: [
            'https://github.com/Anky9972/open-prompt',
            'https://twitter.com/anky_vivek',
        ],
    }
}

export function generateSoftwareApplicationSchema() {
    return {
        '@context': 'https://schema.org',
        '@type': 'SoftwareApplication',
        name: 'OpenPrompt',
        applicationCategory: 'DeveloperApplication',
        operatingSystem: 'Web',
        offers: {
            '@type': 'Offer',
            price: '0',
            priceCurrency: 'USD',
        },
        description: 'AI Prompts Marketplace with 177+ tools, multi-model support, and browser extension',
        featureList: [
            'AI Prompts Marketplace',
            '177+ AI Tools',
            'Multi-Model Support (GPT-4, Claude, Gemini)',
            'Browser Extension',
            'Workflow Automation',
            'Model Comparison (Thunderdome)',
        ],
    }
}

export function generatePromptSchema(prompt: {
    title: string
    description?: string
    slug: string
    creator?: { name?: string }
    createdAt: Date
    updatedAt: Date
    starsCount: number
    totalRuns?: number
    remixesCount?: number
    category?: string
}) {
    const hasEnoughRatings = prompt.starsCount >= 5
    const normalizedRating = hasEnoughRatings
        ? Math.min(5, Math.max(1, 1 + (prompt.starsCount / (prompt.starsCount + 10)) * 4))
        : undefined

    return {
        '@context': 'https://schema.org',
        '@type': 'CreativeWork',
        name: prompt.title,
        description: prompt.description || `AI prompt: ${prompt.title}`,
        url: `${BASE_URL}/p/${prompt.slug}`,
        author: {
            '@type': 'Person',
            name: prompt.creator?.name || 'Anonymous',
        },
        dateCreated: prompt.createdAt.toISOString(),
        dateModified: prompt.updatedAt.toISOString(),
        ...(hasEnoughRatings && normalizedRating && {
            aggregateRating: {
                '@type': 'AggregateRating',
                ratingValue: normalizedRating.toFixed(1),
                ratingCount: prompt.starsCount,
                reviewCount: prompt.starsCount,
                bestRating: 5,
                worstRating: 1,
            },
        }),
        genre: prompt.category || 'AI Prompt',
        isAccessibleForFree: true,
        ...(prompt.totalRuns && {
            interactionStatistic: {
                '@type': 'InteractionCounter',
                interactionType: 'https://schema.org/UseAction',
                userInteractionCount: prompt.totalRuns,
            },
        }),
    }
}

export function generateToolSchema(tool: {
    name: string
    description: string
    slug: string
    category: string
}) {
    return {
        '@context': 'https://schema.org',
        '@type': 'WebApplication',
        name: tool.name,
        description: tool.description,
        url: `${BASE_URL}/tools/${tool.slug}`,
        applicationCategory: 'Productivity',
        operatingSystem: 'Web',
        offers: {
            '@type': 'Offer',
            price: '0',
            priceCurrency: 'USD',
        },
        isAccessibleForFree: true,
    }
}

export function generateBreadcrumbSchema(items: { name: string; url: string }[]) {
    return {
        '@context': 'https://schema.org',
        '@type': 'BreadcrumbList',
        itemListElement: items.map((item, index) => ({
            '@type': 'ListItem',
            position: index + 1,
            name: item.name,
            item: item.url,
        })),
    }
}

export function generateFAQSchema(faqs: { question: string; answer: string }[]) {
    return {
        '@context': 'https://schema.org',
        '@type': 'FAQPage',
        mainEntity: faqs.map((faq) => ({
            '@type': 'Question',
            name: faq.question,
            acceptedAnswer: {
                '@type': 'Answer',
                text: faq.answer,
            },
        })),
    }
}