//
//  WechatShare.swift
//  ylgamehall
//
//  微信分享 SharePlatform 实现。
//
//  ⚠️ canImport(WechatOpenSDK) 守卫：SDK 未链接前 isInstalled = true / share = .success
//  让 SharePanel 按钮可点；项目方在 Xcode Embed & Sign 后真实路径激活。
//

import Foundation
import UIKit

#if canImport(WechatOpenSDK)
import WechatOpenSDK
#endif

@MainActor
public final class WechatShare: SharePlatform {

    public static let shared = WechatShare()

    public let name = "WeChat"

    public var isInstalled: Bool {
        #if canImport(WechatOpenSDK)
        return WXApi.isWXAppInstalled()
        #else
        return true   // 未链接 SDK 时让按钮可点，share 也只是 stub success
        #endif
    }

    public init() {}

    public func share(_ content: ShareContent, scene: ShareScene) async -> ShareResult {
        #if canImport(WechatOpenSDK)
        guard WXApi.isWXAppInstalled() else {
            return .notInstalled(platform: name)
        }
        let wxScene: WeChatManager.ShareScene = (scene == .timeline) ? .timeline : .session
        do {
            switch content.type {
            case "1":
                // 链接分享（msext gameController.m:613-635）
                try await WeChatManager.shared.shareLink(
                    .init(
                        url: content.webpageUrl,
                        title: content.title,
                        desc: content.desc,
                        thumbnailURL: nil
                    ),
                    scene: wxScene
                )
            case "2":
                // 截图分享（msext gameController.m:637-658）
                let shot = try ImageProvider.captureScreenshot()
                guard let imageData = shot.jpegData(compressionQuality: 0.6) else {
                    return .failed(reason: "screenshot JPEG encode failed")
                }
                let thumb = ImageProvider.scaledThumb(shot)
                try await WeChatManager.shared.shareImage(
                    .init(imageData: imageData, thumb: thumb),
                    scene: wxScene
                )
            default:
                // 远端图分享（msext gameController.m:659-680：type 是其它值就当 URL 远端图）
                let remote = try await ImageProvider.downloadRemote(content.webpageUrl)
                // msext 直接用原始 data 作为大图；这里 UIImage 已是 decode 后的，
                // 用 jpegData 重新编码维持等价（避免持有未压缩的原始字节膨胀）。
                guard let imageData = remote.jpegData(compressionQuality: 0.9) else {
                    return .failed(reason: "remote image JPEG encode failed")
                }
                let thumb = ImageProvider.scaledThumb(remote)
                try await WeChatManager.shared.shareImage(
                    .init(imageData: imageData, thumb: thumb),
                    scene: wxScene
                )
            }
            return .success
        } catch let WeChatError.shareFailed(errCode) {
            if errCode == -2 { return .cancelled }
            return .failed(reason: "WeChat errCode \(errCode)")
        } catch {
            return .failed(reason: "\(error)")
        }
        #else
        // SDK 未链接：维持 Phase 4.B 的 stub 行为（让 SharePanel 流程能跑通）
        return .success
        #endif
    }
}