import SnapKit
import UIKit

protocol RDReaderEPUBContentViewDelegate: AnyObject {
    func epubContentView(_ contentView: RDReaderEPUBContentView, didUpdateLocation location: RDEPUBLocation, spineIndex: Int)
    func epubContentView(_ contentView: RDReaderEPUBContentView, didChangeSelection selection: RDEPUBSelection?, spineIndex: Int)
    func epubContentView(_ contentView: RDReaderEPUBContentView, didActivateInternalLink location: RDEPUBLocation, fromSpineIndex: Int)
    func epubContentView(_ contentView: RDReaderEPUBContentView, didActivateExternalLink url: URL)
    func epubContentView(_ contentView: RDReaderEPUBContentView, didLogJavaScriptError message: String)
}

final class RDReaderEPUBContentView: UIView {
    weak var delegate: RDReaderEPUBContentViewDelegate?

    lazy var pageNumLabel: UILabel = {
        let label = UILabel()
        label.font = UIFont.systemFont(ofSize: 13)
        return label
    }()

    private let epubWebView = RDEPUBWebView()

    override init(frame: CGRect) {
        super.init(frame: frame)
        clipsToBounds = true
        layer.masksToBounds = true
        addSubview(epubWebView)
        addSubview(pageNumLabel)

        epubWebView.delegate = self
        epubWebView.clipsToBounds = true
        epubWebView.layer.masksToBounds = true

        epubWebView.snp.makeConstraints { make in
            make.edges.equalToSuperview()
        }
        pageNumLabel.snp.makeConstraints { make in
            make.right.equalToSuperview().offset(-30)
            make.bottom.equalToSuperview().offset(-20)
        }
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    func load(publication: RDEPUBPublication, request: RDEPUBRenderRequest) {
        epubWebView.load(publication: publication, request: request)
    }

    func loadPage(
        parser: RDEPUBParser,
        spineIndex: Int,
        pageIndex: Int,
        totalPagesInChapter: Int,
        viewportSize: CGSize,
        padding: UIEdgeInsets,
        fontSize: CGFloat,
        lineHeightMultiple: CGFloat,
        themeBackgroundColor: String?,
        themeTextColor: String?,
        targetLocation: RDEPUBLocation?,
        highlights: [RDEPUBHighlight]
    ) {
        epubWebView.loadPage(
            parser: parser,
            spineIndex: spineIndex,
            pageIndex: pageIndex,
            totalPagesInChapter: totalPagesInChapter,
            viewportSize: viewportSize,
            padding: padding,
            fontSize: fontSize,
            lineHeightMultiple: lineHeightMultiple,
            themeBackgroundColor: themeBackgroundColor,
            themeTextColor: themeTextColor,
            targetLocation: targetLocation,
            highlights: highlights
        )
    }

    func loadFixedSpread(
        parser: RDEPUBParser,
        spread: EPUBFixedSpread,
        viewportSize: CGSize,
        contentInset: UIEdgeInsets,
        backgroundColor: UIColor?
    ) {
        epubWebView.loadFixedSpread(
            parser: parser,
            spread: spread,
            viewportSize: viewportSize,
            contentInset: contentInset,
            backgroundColor: backgroundColor
        )
    }

    func releaseResources() {
        epubWebView.reset()
        epubWebView.delegate = self
    }

}

extension RDReaderEPUBContentView: RDEPUBWebViewDelegate {
    func epubWebView(_ webView: RDEPUBWebView, didUpdateLocation location: RDEPUBLocation, spineIndex: Int) {
        delegate?.epubContentView(self, didUpdateLocation: location, spineIndex: spineIndex)
    }

    func epubWebView(_ webView: RDEPUBWebView, didChangeSelection selection: RDEPUBSelection?, spineIndex: Int) {
        delegate?.epubContentView(self, didChangeSelection: selection, spineIndex: spineIndex)
    }

    func epubWebView(_ webView: RDEPUBWebView, didActivateInternalLink location: RDEPUBLocation, fromSpineIndex: Int) {
        delegate?.epubContentView(self, didActivateInternalLink: location, fromSpineIndex: fromSpineIndex)
    }

    func epubWebView(_ webView: RDEPUBWebView, didActivateExternalLink url: URL) {
        delegate?.epubContentView(self, didActivateExternalLink: url)
    }

    func epubWebView(_ webView: RDEPUBWebView, didLogJavaScriptError message: String) {
        delegate?.epubContentView(self, didLogJavaScriptError: message)
    }

    func epubWebViewDidFinishRendering(_ webView: RDEPUBWebView) {
    }
}