//
//  WeChatShareService.swift
//  suixinkan
//

import UIKit
import WechatOpenSDK

/// 微信分享服务，封装文本、网页、图片分享能力（不含支付）。
enum WeChatShareService {
    /// 是否已安装微信且支持 Open SDK。
    static var isWeChatAvailable: Bool {
        WXApi.isWXAppInstalled() && WXApi.isWXAppSupport()
    }

    /// 分享纯文本到微信。
    @MainActor
    static func shareText(
        _ payload: WeChatTextSharePayload,
        scene: WeChatShareScene,
        completion: ((WeChatShareResult) -> Void)? = nil
    ) {
        let trimmed = payload.text.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !trimmed.isEmpty else {
            completion?(.invalidPayload("分享文本不能为空"))
            return
        }

        let request = SendMessageToWXReq()
        request.bText = true
        request.text = trimmed
        request.scene = scene.wxSceneValue
        WeChatManager.shared.sendShareRequest(request, completion: completion)
    }

    /// 分享网页链接到微信。
    @MainActor
    static func shareWebPage(
        _ payload: WeChatWebPageSharePayload,
        scene: WeChatShareScene,
        thumbImage: UIImage? = nil,
        completion: ((WeChatShareResult) -> Void)? = nil
    ) {
        let title = payload.title.trimmingCharacters(in: .whitespacesAndNewlines)
        let url = payload.url.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !title.isEmpty else {
            completion?(.invalidPayload("分享标题不能为空"))
            return
        }
        guard !url.isEmpty else {
            completion?(.invalidPayload("分享链接不能为空"))
            return
        }

        let webpageObject = WXWebpageObject()
        webpageObject.webpageUrl = url

        let message = WXMediaMessage()
        message.title = title
        message.description = payload.description
        message.mediaObject = webpageObject
        if let thumbImage, let thumbData = WeChatThumbImageProcessor.makeThumbData(from: thumbImage) {
            message.thumbData = thumbData
        }

        let request = SendMessageToWXReq()
        request.bText = false
        request.message = message
        request.scene = scene.wxSceneValue
        WeChatManager.shared.sendShareRequest(request, completion: completion)
    }

    /// 分享图片到微信。
    @MainActor
    static func shareImage(
        _ payload: WeChatImageSharePayload,
        scene: WeChatShareScene,
        thumbImage: UIImage? = nil,
        completion: ((WeChatShareResult) -> Void)? = nil
    ) {
        guard !payload.imageData.isEmpty else {
            completion?(.invalidPayload("分享图片不能为空"))
            return
        }

        let imageObject = WXImageObject()
        imageObject.imageData = payload.imageData

        let message = WXMediaMessage()
        message.mediaObject = imageObject
        if let thumbImage, let thumbData = WeChatThumbImageProcessor.makeThumbData(from: thumbImage) {
            message.thumbData = thumbData
        } else if let image = UIImage(data: payload.imageData),
                  let thumbData = WeChatThumbImageProcessor.makeThumbData(from: image) {
            message.thumbData = thumbData
        }

        let request = SendMessageToWXReq()
        request.bText = false
        request.message = message
        request.scene = scene.wxSceneValue
        WeChatManager.shared.sendShareRequest(request, completion: completion)
    }

    /// 获取 App 图标，用作分享缩略图兜底。
    static func defaultThumbImage() -> UIImage? {
        guard let icons = Bundle.main.infoDictionary?["CFBundleIcons"] as? [String: Any],
              let primary = icons["CFBundlePrimaryIcon"] as? [String: Any],
              let iconFiles = primary["CFBundleIconFiles"] as? [String],
              let iconName = iconFiles.last else {
            return nil
        }
        return UIImage(named: iconName)
    }
}