'use strict';

const path = require('path');

const util = require('util');

const stream = require('stream');

const events = require('events');

const semver = require('semver');

const is = require('./is');

const platform = require('./platform');

const sharp = require('../build/Release/sharp.node');

// Vendor platform

(function () {

let vendorPlatformId;

try {

vendorPlatformId = require('../vendor/platform.json');

} catch (err) {

return;

}

const currentPlatformId = platform();

/* istanbul ignore if */

if (currentPlatformId !== vendorPlatformId) {

throw new Error(`'${vendorPlatformId}' binaries cannot be used on the '${currentPlatformId}' platform. Please remove the 'node_modules/sharp/vendor' directory and run 'npm rebuild'.`);

}

})();

// Versioning

let versions = {

vips: sharp.libvipsVersion()

};

(function () {

// Does libvips meet minimum requirement?

const libvipsVersionMin = require('../package.json').config.libvips;

/* istanbul ignore if */

if (semver.lt(versions.vips, libvipsVersionMin)) {

throw new Error('Found libvips ' + versions.vips + ' but require at least ' + libvipsVersionMin);

}

// Include versions of dependencies, if present

try {

versions = require('../vendor/versions.json');

} catch (err) {}

})();

// Use NODE_DEBUG=sharp to enable libvips warnings

const debuglog = util.debuglog('sharp');

/**

* @class Sharp

*

* Constructor factory to create an instance of `sharp`, to which further methods are chained.

*

* JPEG, PNG, WebP or TIFF format image data can be streamed out from this object.

* When using Stream based output, derived attributes are available from the `info` event.

*

* Implements the [stream.Duplex](http://nodejs.org/api/stream.html#stream_class_stream_duplex) class.

*

* @example

* sharp('input.jpg')

* .resize(300, 200)

* .toFile('output.jpg', function(err) {

* // output.jpg is a 300 pixels wide and 200 pixels high image

* // containing a scaled and cropped version of input.jpg

* });

*

* @example

* // Read image data from readableStream,

* // resize to 300 pixels wide,

* // emit an 'info' event with calculated dimensions

* // and finally write image data to writableStream

* var transformer = sharp()

* .resize(300)

* .on('info', function(info) {

* console.log('Image height is ' + info.height);

* });

* readableStream.pipe(transformer).pipe(writableStream);

*

* @example

* // Create a blank 300x200 PNG image of semi-transluent red pixels

* sharp({

* create: {

* width: 300,

* height: 200,

* channels: 4,

* background: { r: 255, g: 0, b: 0, alpha: 128 }

* }

* })

* .png()

* .toBuffer()

* .then( ... );

*

* @param {(Buffer|String)} [input] - if present, can be

* a Buffer containing JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data, or

* a String containing the path to an JPEG, PNG, WebP, GIF, SVG or TIFF image file.

* JPEG, PNG, WebP, GIF, SVG, TIFF or raw pixel image data can be streamed into the object when not present.

* @param {Object} [options] - if present, is an Object with optional attributes.

* @param {Boolean} [options.failOnError=false] - by default apply a "best effort"

* to decode images, even if the data is corrupt or invalid. Set this flag to true

* if you'd rather halt processing and raise an error when loading invalid images.

* @param {Number} [options.density=72] - integral number representing the DPI for vector images.

* @param {Number} [options.page=0] - page number to extract for multi-page input (GIF, TIFF)

* @param {Object} [options.raw] - describes raw pixel input image data. See `raw()` for pixel ordering.

* @param {Number} [options.raw.width]

* @param {Number} [options.raw.height]

* @param {Number} [options.raw.channels] - 1-4

* @param {Object} [options.create] - describes a new image to be created.

* @param {Number} [options.create.width]

* @param {Number} [options.create.height]

* @param {Number} [options.create.channels] - 3-4

* @param {String|Object} [options.create.background] - parsed by the [color](https://www.npmjs.org/package/color) module to extract values for red, green, blue and alpha.

* @returns {Sharp}

* @throws {Error} Invalid parameters

*/

const Sharp = function (input, options) {

};

util.inherits(Sharp, stream.Duplex);

/**

* An EventEmitter that emits a `change` event when a task is either:

* - queued, waiting for _libuv_ to provide a worker thread

* - complete

* @member

* @example

* sharp.queue.on('change', function(queueLength) {

* console.log('Queue contains ' + queueLength + ' task(s)');

* });

*/

const queue = new events.EventEmitter();

Sharp.queue = queue;

/**

* An Object containing nested boolean values representing the available input and output formats/methods.

* @example

* console.log(sharp.format);

* @returns {Object}

*/

Sharp.format = sharp.format();

/**

* An Object containing the version numbers of libvips and its dependencies.

* @member

* @example

* console.log(sharp.versions);

*/

Sharp.versions = versions;

/**

* Export constructor.

* @private

*/

module.exports = Sharp;