import Foundation

struct IndexPageGenerator {

    private let factory: LocalizedSiteTemplate

    init(factory: LocalizedSiteTemplate) {
        self.factory = factory
    }

    func generate(site: Element, language: String) {
        let localized = site.localized(for: language)
        let path = site.localizedPath(for: language)
        let pageUrl = files.urlInOutputFolder(path)
        let languageButton = site.nextLanguage(for: language)
        let sectionItemCount = site.overviewItemCount

        var content = [PageTemplate.Key : String]()
        content[.head] = factory.pageHead.generate(page: site, language: language)
        content[.topBar] = factory.topBar.generate(sectionUrl: nil, languageButton: languageButton)
        content[.contentClass] = "overview"
        content[.header] = makeHeader(page: site, metadata: localized, language: language)
        content[.content] = factory.overviewSection.generate(
            sections: site.sortedItems,
            in: site,
            language: language,
            sectionItemCount: sectionItemCount)
        content[.footer] = site.customFooterContent()
        guard factory.page.generate(content, to: pageUrl) else {
            return
        }
        files.generated(page: path)
    }

    private func makeHeader(page: Element, metadata: Element.LocalizedMetadata, language: String) -> String {
        let content = factory.makeHeaderContent(page: page, metadata: metadata, language: language)
        return factory.factory.centeredHeader.generate(content)
    }
}