import ImageProvider, { ProvidedImage } from "./ImageProvider"
import BaseUIElement from "../../UI/BaseUIElement"
import Svg from "../../Svg"
import { WikimediaImageProvider } from "./WikimediaImageProvider"
import Wikidata from "../Web/Wikidata"

export class WikidataImageProvider extends ImageProvider {
    public static readonly singleton = new WikidataImageProvider()
    public readonly defaultKeyPrefixes = ["wikidata"]

    private constructor() {
        super()
    }

    public SourceIcon(backlinkSource?: string): BaseUIElement {
        throw Svg.wikidata_svg()
    }

    public async ExtractUrls(key: string, value: string): Promise<Promise<ProvidedImage>[]> {
        const entity = await Wikidata.LoadWikidataEntryAsync(value)
        if (entity === undefined) {
            return []
        }

        const allImages: Promise<ProvidedImage>[] = []
        // P18 is the claim 'depicted in this image'
        for (const img of Array.from(entity.claims.get("P18") ?? [])) {
            const promises = await WikimediaImageProvider.singleton.ExtractUrls(undefined, img)
            allImages.push(...promises)
        }
        // P373 is 'commons category'
        for (let cat of Array.from(entity.claims.get("P373") ?? [])) {
            if (!cat.startsWith("Category:")) {
                cat = "Category:" + cat
            }
            const promises = await WikimediaImageProvider.singleton.ExtractUrls(undefined, cat)
            allImages.push(...promises)
        }

        const commons = entity.commons
        if (
            commons !== undefined &&
            (commons.startsWith("Category:") || commons.startsWith("File:"))
        ) {
            const promises = await WikimediaImageProvider.singleton.ExtractUrls(undefined, commons)
            allImages.push(...promises)
        }
        return allImages
    }

    public DownloadAttribution(url: string): Promise<any> {
        throw new Error("Method not implemented; shouldn't be needed!")
    }
}