import { A4_EXPORT_SIZE_150DPI } from '../constants/colors';

/**
 * 导出为固定打印分辨率（A4 150 DPI），避免高 DPR 设备导出过大图导致打印慢、文件大
 */
const doSaveImage = (canvas: Canvas): Promise<boolean> =>
    new Promise((resolve) => {
        const { width: destWidth, height: destHeight } = A4_EXPORT_SIZE_150DPI;
        wx.canvasToTempFilePath({
            canvas,
            fileType: 'jpg',
            quality: 0.9,
            destWidth,
            destHeight,
            success: (res) => {
                wx.saveImageToPhotosAlbum({
                    filePath: res.tempFilePath,
                    success: () => {
                        wx.showToast({
                            title: '保存成功，请在相册中查看',
                            icon: 'success',
                            duration: 2000,
                        });
                        resolve(true);
                    },
                    fail: () => {
                        wx.showToast({
                            title: '保存涂色卡失败，请重试！',
                            icon: 'none',
                            duration: 2000,
                        });
                        resolve(false);
                    },
                });
            },
            fail: () => {
                wx.showToast({
                    title: '生成涂色卡失败，请重试！',
                    icon: 'none',
                    duration: 2000,
                });
                resolve(false);
            },
        });
    });

const requestPhotoPermission = (canvas: Canvas): Promise<boolean> =>
    new Promise((resolve) => {
        wx.authorize({
            scope: 'scope.writePhotosAlbum',
            success: () => {
                doSaveImage(canvas).then(resolve);
            },
            fail: () => {
                wx.showToast({
                    title: '请在“设置-添加到相册”中开启相册权限以保存涂色卡',
                    icon: 'none',
                    duration: 3000,
                });
                resolve(false);
            },
        });
    });

export const checkAndSaveImage = (canvas: Canvas): Promise<boolean> =>
    new Promise((resolve) => {
        wx.getSetting({
            success: (res) => {
                if (!res.authSetting['scope.writePhotosAlbum']) {
                    requestPhotoPermission(canvas).then(resolve);
                } else {
                    doSaveImage(canvas).then(resolve);
                }
            },
            fail: () => resolve(false),
        });
    });