import Foundation

class MoebooruPostXMLParser: NSObject, XMLParserDelegate {
    private var posts: [MoebooruPost] = []
    private var currentPost: MoebooruPost?
    private var parser: XMLParser

    init(data: Data) {
        parser = XMLParser(data: data)

        super.init()

        parser.delegate = self
    }

    func parse() -> [MoebooruPost] {
        parser.parse()

        return posts
    }

    func parser(_: XMLParser, didStartElement elementName: String, namespaceURI _: String?, qualifiedName _: String?, attributes attributeDict: [String: String] = [:]) {
        if elementName == "post" {
            guard let id = attributeDict["id"],
                  let tags = attributeDict["tags"],
                  let createdAtStr = attributeDict["created_at"],
                  let createdAt = Int(createdAtStr),
                  let updatedAtStr = attributeDict["updated_at"],
                  let updatedAt = Int(updatedAtStr),
                  let creatorId = attributeDict["creator_id"],
                  let approverId = attributeDict["approver_id"],
                  let author = attributeDict["author"],
                  let change = attributeDict["change"],
                  let source = attributeDict["source"],
                  let score = attributeDict["score"],
                  let md5 = attributeDict["md5"],
                  let fileSizeStr = attributeDict["file_size"],
                  let fileSize = Int(fileSizeStr),
                  let fileExt = attributeDict["file_ext"],
                  let fileUrl = attributeDict["file_url"],
                  let isShownStr = attributeDict["is_shown_in_index"],
                  let previewUrl = attributeDict["preview_url"],
                  let previewWidthStr = attributeDict["preview_width"],
                  let previewWidth = Int(previewWidthStr),
                  let previewHeightStr = attributeDict["preview_height"],
                  let previewHeight = Int(previewHeightStr),
                  let actualPreviewWidthStr = attributeDict["actual_preview_width"],
                  let actualPreviewWidth = Int(actualPreviewWidthStr),
                  let actualPreviewHeightStr = attributeDict["actual_preview_height"],
                  let actualPreviewHeight = Int(actualPreviewHeightStr),
                  let sampleUrl = attributeDict["sample_url"],
                  let sampleWidthStr = attributeDict["sample_width"],
                  let sampleWidth = Int(sampleWidthStr),
                  let sampleHeightStr = attributeDict["sample_height"],
                  let sampleHeight = Int(sampleHeightStr),
                  let sampleFileSizeStr = attributeDict["sample_file_size"],
                  let sampleFileSize = Int(sampleFileSizeStr),
                  let jpegUrl = attributeDict["jpeg_url"],
                  let jpegWidthStr = attributeDict["jpeg_width"],
                  let jpegWidth = Int(jpegWidthStr),
                  let jpegHeightStr = attributeDict["jpeg_height"],
                  let jpegHeight = Int(jpegHeightStr),
                  let jpegFileSizeStr = attributeDict["jpeg_file_size"],
                  let jpegFileSize = Int(jpegFileSizeStr),
                  let rating = attributeDict["rating"],
                  let isRatingLockedStr = attributeDict["is_rating_locked"],
                  let hasChildrenStr = attributeDict["has_children"],
                  let parentId = attributeDict["parent_id"],
                  let status = attributeDict["status"],
                  let isPendingStr = attributeDict["is_pending"],
                  let widthStr = attributeDict["width"],
                  let width = Int(widthStr),
                  let heightStr = attributeDict["height"],
                  let height = Int(heightStr),
                  let isHeldStr = attributeDict["is_held"],
                  let framesPendingString = attributeDict["frames_pending_string"],
                  let framesString = attributeDict["frames_string"],
                  let isNoteLockedStr = attributeDict["is_note_locked"],
                  let lastNotedAtStr = attributeDict["last_noted_at"],
                  let lastNotedAt = Int(lastNotedAtStr),
                  let lastCommentedAtStr = attributeDict["last_commented_at"],
                  let lastCommentedAt = Int(lastCommentedAtStr)
            else {
                return
            }

            currentPost = MoebooruPost(
                id: id,
                tags: tags.components(separatedBy: " "),
                createdAt: createdAt,
                updatedAt: updatedAt,
                creatorID: creatorId,
                approverID: approverId,
                author: author,
                change: change,
                source: source,
                score: score,
                md5: md5,
                fileSize: fileSize,
                fileExtension: fileExt,
                fileURL: URL(string: fileUrl)!,
                isShownInIndex: isShownStr == "true",
                previewURL: URL(string: previewUrl)!,
                previewWidth: previewWidth,
                previewHeight: previewHeight,
                actualPreviewWidth: actualPreviewWidth,
                actualPreviewHeight: actualPreviewHeight,
                sampleURL: URL(string: sampleUrl)!,
                sampleWidth: sampleWidth,
                sampleHeight: sampleHeight,
                sampleFileSize: sampleFileSize,
                jpegURL: URL(string: jpegUrl)!,
                jpegWidth: jpegWidth,
                jpegHeight: jpegHeight,
                jpegFileSize: jpegFileSize,
                rating: rating,
                isRatingLocked: isRatingLockedStr == "true",
                hasChildren: hasChildrenStr == "true",
                parentId: parentId,
                status: status,
                isPending: isPendingStr == "true",
                width: width,
                height: height,
                isHeld: isHeldStr == "true",
                framesPendingString: framesPendingString,
                framesString: framesString,
                isNoteLocked: isNoteLockedStr == "true",
                lastNotedAt: lastNotedAt,
                lastCommentedAt: lastCommentedAt
            )
        }
    }

    func parser(_: XMLParser, didEndElement elementName: String, namespaceURI _: String?, qualifiedName _: String?) {
        if elementName == "post", let post = currentPost {
            posts.append(post)

            currentPost = nil
        }
    }

    #if DEBUG
        func parser(_: XMLParser, parseErrorOccurred parseError: any Error) {
            print(parseError)
        }
    #endif
}