import Foundation

extension Content {

    func saveToDisk() throws {
        //print("Starting save")
        for page in pages {
            try storage.save(pageMetadata: page.pageFile, for: page.id)
        }

        for post in posts {
            try storage.save(post: post.postFile, for: post.id)
        }

        for tag in tags {
            try storage.save(tagMetadata: tag.tagFile, for: tag.id)
        }
        try storage.save(settings: settings.file)

        let fileDescriptions: [FileDescriptions] = files.sorted().compactMap { file in
            guard !file.englishDescription.isEmpty || !file.germanDescription.isEmpty else {
                return nil
            }
            return FileDescriptions(
                fileId: file.id,
                german: file.germanDescription.nonEmpty,
                english: file.englishDescription.nonEmpty)
        }

        try storage.save(fileDescriptions: fileDescriptions)

        do {
            try storage.deletePostFiles(notIn: posts.map { $0.id })
            try storage.deletePageFiles(notIn: pages.map { $0.id })
            try storage.deleteTagFiles(notIn: tags.map { $0.id })
            try storage.deleteFileResources(notIn: files.map { $0.id })
        } catch {
            print("Failed to remove unused files: \(error)")
        }
    }
}

private extension Page {

    var pageFile: PageFile {
        .init(isDraft: isDraft,
              tags: tags.map { $0.id },
              createdDate: createdDate,
              startDate: startDate,
              endDate: hasEndDate ? endDate : nil,
              german: german.pageFile,
              english: english.pageFile)
    }
}

private extension LocalizedPage {

    var pageFile: LocalizedPageFile {
        .init(url: urlString,
              files: files.sorted(),
              externalFiles: externalFiles.sorted(),
              requiredFiles: requiredFiles.sorted(),
              title: title,
              linkPreviewImage: linkPreviewImage?.id,
              linkPreviewTitle: linkPreviewTitle,
              linkPreviewDescription: linkPreviewDescription,
              lastModifiedDate: lastModified,
              originalURL: originalUrl)
    }
}


private extension Post {

    var postFile: PostFile {
        .init(
            isDraft: isDraft,
            createdDate: createdDate,
            startDate: startDate,
            endDate: hasEndDate ? endDate : nil,
            tags: tags.map { $0.id },
            german: german.postFile,
            english: english.postFile,
            linkedPageId: linkedPage?.id)
    }
}

private extension LocalizedPost {

    var postFile: LocalizedPostFile {
        .init(images: images.map { $0.id },
              title: title.nonEmpty,
              content: content,
              lastModifiedDate: lastModified,
              linkPreviewImage: linkPreviewImage?.id,
              linkPreviewTitle: linkPreviewTitle,
              linkPreviewDescription: linkPreviewDescription)
    }
}


private extension Tag {

    var tagFile: TagFile {
        .init(id: id,
              isVisible: isVisible,
              german: german.tagFile,
              english: english.tagFile)
    }
}

private extension LocalizedTag {

    var tagFile: LocalizedTagFile {
        .init(urlComponent: urlComponent,
              name: name,
              subtitle: subtitle,
              description: description,
              thumbnail: thumbnail?.id,
              originalURL: originalUrl)
    }
}

private extension NavigationBarSettings {

    var file: NavigationBarSettingsFile {
        .init(navigationIconPath: iconPath,
              navigationTags: tags.map { $0.id })
    }
}

extension Settings {

    var file: SettingsFile {
        .init(
            outputDirectoryPath: outputDirectoryPath,
            navigationBar: navigationBar.file,
            posts: posts.file,
            pages: pages.file,
            german: german.file,
            english: english.file)
    }
}

private extension PostSettings {

    var file: PostSettingsFile {
        .init(postsPerPage: postsPerPage,
              contentWidth: contentWidth)
    }
}

private extension PageSettings {

    var file: PageSettingsFile {
        .init(pageUrlPrefix: pageUrlPrefix,
              contentWidth: contentWidth)
    }
}

private extension LocalizedSettings {

    var file: LocalizedSettingsFile {
        .init(navigationBarIconDescription: navigationBarIconDescription,
              posts: posts.file)
    }
}

private extension LocalizedPostSettings {

    var file: LocalizedPostSettingsFile {
        .init(
            feedTitle: title,
            feedDescription: description,
            feedUrlPrefix: feedUrlPrefix)
    }
}