CHGenerator/Sources/Generator/Generators/HTMLElementsGenerator.swift

import Foundation

typealias SVGSelection = (x: Int, y: Int, width: Int, height: Int)

struct HTMLElementsGenerator {

    func make(title: String, suffix: String) -> String {
        "\(title)<span class=\"suffix\">\(suffix)</span>"
    }

    func topBarWebsiteTitle(language: String, from page: Element) -> String {
        guard let pathToRoot = page.pathToRoot else {
            return Element.htmlPageName(for: language)
        }
        return pathToRoot + Element.htmlPagePathAddition(for: language)
    }

    func topBarLanguageButton(_ language: String) -> String {
        "<a href=\"\(Element.htmlPageName(for: language))\">\(language)</a>"
    }

    func topBarNavigationLink(url: String, text: String, isActive: Bool) -> String {
        "<a\(isActive ? " class=\"active\"" : "") href=\"/\(url)\">\(text)</a>"
    }

    func linkPreviewImage(file: String) -> String {
        "<meta property=\"og:image\" content=\"\(file)\" />"
    }

    func makePrevText(_ text: String) -> String {
        "<span class=\"icon-back\"></span>\(text)"
    }

    func makeNextText(_ text: String) -> String {
        "\(text)<span class=\"icon-next\"></span>"
    }

    func image(file: String, width: Int, height: Int, altText: String) -> String {
        let ratio = Float(width) / Float(height)
        return """
        <span class="image">
            <img src="\(file)" loading="lazy" style="aspect-ratio:\(ratio)" alt="\(altText)"/>
        </span>
        """
    }

    func svgImage(file: String, part: SVGSelection, altText: String) -> String {
        let path = "\(file)#svgView(viewBox(\(part.x), \(part.y), \(part.width), \(part.height)))"
        return image(file: path, width: part.width, height: part.height, altText: altText)
    }

    func downloadButtons(_ buttons: [(file: String, text: String, downloadName: String?)]) -> String {
        let content = buttons.map {
            if let download = $0.downloadName {
                return button(file: $0.file, text: $0.text, downloadName: download)
            } else {
                return button(file: $0.file, text: $0.text)
            }
        }.joined(separator: "\n")
        return flexParagraph(content)
    }

    func externalButtons(_ buttons: [(url: String, text: String)]) -> String {
        let content = buttons
            .map { externalLink(url: $0.url, text: $0.text) }
            .joined(separator: "\n")
        return flexParagraph(content)
    }

    private func flexParagraph(_ content: String) -> String {
        """
        <p style="display: flex">
        \(content)
        </p>
        """
    }

    private func button(file: String, text: String) -> String {
        """
        <a class="download-button" href="\(file)">
            \(text)<span class="icon icon-download"></span>
        </a>
        """
    }

    private func button(file: String, text: String, downloadName: String) -> String {
        """
        <a class="download-button" href="\(file)" download="\(downloadName)">
            \(text)<span class="icon icon-download"></span>
        </a>
        """
    }

    private func externalLink(url: String, text: String) -> String {
        """
        <a class="download-button" href="\(url)">
            \(text)<span class="icon icon-download icon-rotate"></span>
        </a>
        """
    }

    func scriptInclude(path: String, asModule: Bool) -> String {
        if asModule {
            return "<script type=\"module\" src=\"\(path)\"></script>"
        }
        return "<script src=\"\(path)\"></script>"
    }

    func codeHighlightFooter() -> String {
        "<script>hljs.highlightAll();</script>"
    }
}