import Elementary
import Foundation
import Localization

/// The website's landing page, with its text localized to a given locale.
struct IndexPage: HTMLDocument, Sendable {

    // MARK: Properties

    /// The locale the page content is localized to.
    private let locale: Locale

    /// Resolves the page's text from the bundled String Catalog for the page's ``locale``.
    private let localize: Localize

    // MARK: Initializers

    /// Creates a landing page localized to the given locale.
    /// - Parameter locale: the locale the page content is localized to.
    init(
        locale: Locale
    ) {
        self.locale = locale
        self.localize = .init(bundle: .module)
    }

    // MARK: Document

    /// The page's content: a localized greeting followed by the shared and index scripts.
    var body: some HTML {
        p {
            localize("index.greeting", locale: locale)
        }
        script(.src(StaticFile.index.urlPath(for: .js))) {}
        script(.src(StaticFile.shared.urlPath(for: .js))) {}
    }

    /// The metadata, stylesheet, icon, and manifest links placed in the document head.
    var head: some HTML {
        meta(.charset(.utf8))
        meta(
            .name(.viewport),
            .content("width=device-width, initial-scale=1")
        )
        link(
            .rel(.stylesheet),
            .href(StaticFile.shared.urlPath(for: .css))
        )
        link(
            .rel(.stylesheet),
            .href(StaticFile.index.urlPath(for: .css))
        )
        link(
            .rel(.icon),
            .href(StaticFile.favicon.urlPath(for: .ico)),
            .custom(
                name: "sizes",
                value: "any"
            )
        )
        link(
            .rel(.icon),
            .href(StaticFile.icon.urlPath(for: .svg)),
            .custom(
                name: "type",
                value: "image/svg+xml"
            )
        )
        link(
            .rel("apple-touch-icon"),
            .href(StaticFile.appleTouchIcon.urlPath(for: .png))
        )
        link(
            .rel("manifest"),
            .href(StaticFile.site.urlPath(for: .webmanifest))
        )
        meta(
            .name("theme-color"),
            .content("#fafafa")
        )
    }

    /// The document language, derived from the page's locale and falling back to the default language.
    var lang: String {
        locale.language.languageCode?.identifier
            ?? LanguageList(bundle: .module).default
    }

    /// The localized document title.
    var title: String {
        localize("index.title", locale: locale)
    }

}