"use strict";
var vows = require("vows"),
    load = require("../load"),
    assert = require("assert"),
    jsdom = require("jsdom");

var suite = vows.describe("mp.dye");

var dyeString = "R:#ede5b2,fff7bf;G:#cccccc,ffffff";
var dyeData = {
    "R": [
        [0xed, 0xe5, 0xb2],
        [0xff, 0xf7, 0xbf]
    ],
    "G": [
        [0xcc, 0xcc, 0xcc],
        [0xff, 0xff, 0xff]
    ]
};

function assertImageDataEqual(input, expected, actual, width) {
    assert.equal(actual.length, expected.length, "expected same " + expected.length + " pixel components, found " + actual.length);
    for (var i = 0; i != actual.length; i += 4) {
        var p = i / 4;
        var y = Math.floor(p / width);
        var x = p - y * width;
        var msg = "At (" + x + "," + y + "): "
                + "Input rgba(" + input   [i    ] + "," + input   [i + 1] + "," + input   [i + 2] + "," + input   [i + 3] + ") "
        + "should dye to rgba(" + expected[i    ] + "," + expected[i + 1] + "," + expected[i + 2] + "," + expected[i + 3] + "); "
                + "found rgba(" + actual  [i    ] + "," + actual  [i + 1] + "," + actual  [i + 2] + "," + actual  [i + 3] + ")";
        assert.equal(actual[i    ], expected[i    ], msg);
        assert.equal(actual[i + 1], expected[i + 1], msg);
        assert.equal(actual[i + 2], expected[i + 2], msg);
        assert.equal(actual[i + 3], expected[i + 3], msg);
    }
}

function unshiftLoadImageBind(url, tests) {
    tests.topic = function() {
        var mp = arguments[arguments.length - 1];
        var tester = this;
        var args = arguments;
        mp.resource.loadImage(url, function(err, data) {
            if (err) {
                throw new Error("Error loading '" + url + "': " + data);
            }
            tester.callback.bind(tester, err, data).apply(tester, args);
        });
    };
    return tests;
}

function testDye(err, dyed, dyeable, mp) {
    var input = dyeable.data;
    var expected = dyed.data;
    var actual = new Uint8ClampedArray(input);
    mp.dye.dyeImage(actual, dyeData);
    assertImageDataEqual(input, expected, actual, dyed.width);
}

suite.addBatch({
    "The manaportal dye": {
        topic: load("mp/dye", "mp/resource").expression("mp").document(),
        "parseDyeString": {
            "extracts the dye channel data from the dyestring": function(mp) {
                assert.equal(mp.dye.parseDyeString(dyeString), dyeData);
            }
        },
        "asDyeString": {
            "reconstructs the dyestring from the dye channel data": function(mp) {
                assert.equal(mp.dye.asDyeString(dyeData), dyeString);
            }
        },
        "dyeImage": {
            "with the big recolorable cake": unshiftLoadImageBind("test/data/bigcake.png", {
                "to the big white cake dyed by TMWW": unshiftLoadImageBind("test/data/whitecake.png", {
                    "dyes correctly when given the correct dye data": testDye
                })
            }),
            "with a gradient of all channels with all intensities": unshiftLoadImageBind("test/data/gradient.png", {
                "to a gradient of all channels with all intensities dyed by TMWW with the white cake dye": unshiftLoadImageBind("test/data/gradient-whitecakedye.png", {
                    "dyes correctly when given the correct dye data": testDye
                })
            })
        }
    }
});

suite.export(module);