nodebb/src/image.js

'use strict';

var fs = require('fs');
var Jimp = require('jimp');
var async = require('async');
var plugins = require('./plugins');

var image = module.exports;

image.resizeImage = function (data, callback) {
	if (plugins.hasListeners('filter:image.resize')) {
		plugins.fireHook('filter:image.resize', {
			path: data.path,
			target: data.target,
			extension: data.extension,
			width: data.width,
			height: data.height
		}, function (err) {
			callback(err);
		});
	} else {
		new Jimp(data.path, function (err, image) {
			if (err) {
				return callback(err);
			}

			var w = image.bitmap.width,
				h = image.bitmap.height,
				origRatio = w / h,
				desiredRatio = data.width && data.height ? data.width / data.height : origRatio,
				x = 0,
				y = 0,
				crop;

			if (origRatio !== desiredRatio) {
				if (desiredRatio > origRatio) {
					desiredRatio = 1 / desiredRatio;
				}
				if (origRatio >= 1) {
					y = 0;	// height is the smaller dimension here
					x = Math.floor((w / 2) - (h * desiredRatio / 2));
					crop = async.apply(image.crop.bind(image), x, y, h * desiredRatio, h);
				} else {
					x = 0;	// width is the smaller dimension here
					y = Math.floor(h / 2 - (w * desiredRatio / 2));
					crop = async.apply(image.crop.bind(image), x, y, w, w * desiredRatio);
				}
			} else {
				// Simple resize given either width, height, or both
				crop = async.apply(setImmediate);
			}

			async.waterfall([
				crop,
				function (_image, next) {
					if (typeof _image === 'function' && !next) {
						next = _image;
						_image = image;
					}

					if ((data.width && data.height) || (w > data.width) || (h > data.height)) {
						_image.resize(data.width || Jimp.AUTO, data.height || Jimp.AUTO, next);
					} else {
						next(null, image);
					}
				},
				function (image, next) {
					if (data.write === false) {
						return next();
					}
					image.write(data.target || data.path, next);
				}
			], function (err) {
				callback(err);
			});
		});
	}
};

image.normalise = function (path, extension, callback) {
	if (plugins.hasListeners('filter:image.normalise')) {
		plugins.fireHook('filter:image.normalise', {
			path: path,
			extension: extension
		}, function (err) {
			callback(err);
		});
	} else {
		new Jimp(path, function (err, image) {
			if (err) {
				return callback(err);
			}
			image.write(path + '.png', function (err) {
				callback(err);
			});
		});
	}
};

image.size = function (path, callback) {
	if (plugins.hasListeners('filter:image.size')) {
		plugins.fireHook('filter:image.size', {
			path: path,
		}, function (err, image) {
			callback(err, image);
		});
	} else {
		new Jimp(path, function (err, data) {
			callback(err, data ? data.bitmap : null);
		});
	}
};

image.convertImageToBase64 = function (path, callback) {
	fs.readFile(path, function (err, data) {
		callback(err, data ? data.toString('base64') : null);
	});
};