import { checkImage } from "check-image-type"
import { toUnit8Array } from "../../bit"

/**
 * 检查一个 Blob 或 File 的类型是否为图片，并返回具体类型
 * @returns 如果是图片，返回 { ext: string, mime: string }，否则返回 undefined
 */
export async function checkImageType(blob: Blob | File): Promise<{
    ext: string
    mime: string
} | void> {
    // 优先根据 blob.type 判断
    if (blob.type) {
        for (const key in IMAGE_TYPES) {
            if (IMAGE_TYPES[key].mime === blob.type) {
                return IMAGE_TYPES[key]
            }
        }
    }
    // 否则用 checkImage 检查
    return checkImage(await toUnit8Array(blob))
}

/**
 * 所有图片类型定义，Key 为类型（ext）
 */
const IMAGE_TYPES: any = {
    webp: { ext: "webp", mime: "image/webp" },
    jpg: { ext: "jpg", mime: "image/jpeg" },
    png: { ext: "png", mime: "image/png" },
    bmp: { ext: "bmp", mime: "image/bmp" },
    gif: { ext: "gif", mime: "image/gif" },
    avif: { ext: "avif", mime: "image/avif" },
    heic: { ext: "heic", mime: "image/heic" },
    bpg: { ext: "bpg", mime: "image/bpg" },
    ico: { ext: "ico", mime: "image/ico" },
    psd: { ext: "psd", mime: "image/vnd.adobe.photoshop" },
    jxr: { ext: "jxr", mime: "image/vnd.ms-photo" },
    flif: { ext: "flif", mime: "image/flif" },
    icns: { ext: "icns", mime: "image/icns" },
    orf: { ext: "orf", mime: "image/x-olympus-orf" },
    xcf: { ext: "xcf", mime: "image/x-xcf" },
    rw2: { ext: "rw2", mime: "image/x-panasonic-rw2" },
    ktx: { ext: "ktx", mime: "image/ktx" },
    jxl: { ext: "jxl", mime: "image/jxl" },
    cur: { ext: "cur", mime: "image/x-icon" },
    raf: { ext: "raf", mime: "image/x-fujifilm-raf" },
} as const