defineSuite([
        'Renderer/modernizeShader'
    ], function(
        modernizeShader) {
    'use strict';

    it('adds version string', function() {
        var simple =
            '#define OUTPUT_DECLARATION \n' +
            'void main() \n' +
            '{ \n' +
            '} \n';
        var output = modernizeShader(simple, true);
        var expected = '#version 300 es';
        expect(output.split('\n')[0]).toEqual(expected);
    });

    it('removes extensions', function() {
        var extensions =
            '#define OUTPUT_DECLARATION \n' +
            '#extension GL_EXT_draw_buffers : enable \n' +
            'void main() \n' +
            '{ \n' +
            '} \n';
        var output = modernizeShader(extensions, true);
        var notExpected = '#extension GL_EXT_draw_buffers : enable \n';
        expect(output).not.toContain(notExpected);
    });

    it('throws exception if no output declaration', function() {
         var noOutputDeclaration =
            'void main() \n' +
            '{ \n' +
            '} \n';
        var runFunc = function() {
            modernizeShader(noOutputDeclaration, true);
        };
        expect(runFunc).toThrowDeveloperError();
    });

    it('creates layout qualifier for gl_FragColor', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            'void main() \n' +
            '{ \n' +
            '    gl_FragColor = vec4(0.0); \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected = 'layout(location = 0) out vec4 czm_fragColor;';
        expect(output).toContain(expected);
    });

    it('creates layout qualifier for gl_FragData', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            'void main() \n' +
            '{ \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected = 'layout(location = 0) out vec4 czm_out0;';
        expect(output).toContain(expected);
    });

    it('creates layout qualifier for MRT', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#extension GL_EXT_draw_buffers : enable \n' +
            'void main() \n' +
            '{ \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    gl_FragData[1] = vec4(1.0); \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected0 = 'layout(location = 0) out vec4 czm_out0;';
        var expected1 = 'layout(location = 1) out vec4 czm_out1;';
        expect(output).toContain(expected0);
        expect(output).toContain(expected1);
    });

    it('does not create layout qualifier for reserved word lookalike variables', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            'uniform sampler2D example; \n' +
            'void main() \n' +
            '{ \n' +
            '    vec4 gl_FragData_ = vec4(0.0); \n' +
            '    vec4 a_gl_FragData = vec4(0.0); \n' +
            '    vec2 thisIsNotAGoodNameForAtexture2D = vec2(0.0); \n' +
            '    vec4 gl_FragColor = texture2D(example, thisIsNotAGoodNameForAtexture2D); \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expectedBadName = 'vec2 thisIsNotAGoodNameForAtexture2D';
        var expectedVariable = 'vec4 a_gl_FragData = vec4(0.0);';
        var expectedTextureCall = 'texture(example, thisIsNotAGoodNameForAtexture2D)';
        var notExpectedLayout = 'layout(location = 0) out czm_out';
        expect(output).toContain(expectedBadName);
        expect(output).toContain(expectedVariable);
        expect(output).toContain(expectedTextureCall);
        expect(output).not.toContain(notExpectedLayout);
    });

    it('creates layout qualifier with swizzle', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#extension GL_EXT_draw_buffers : enable \n' +
            'void main() \n' +
            '{ \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    gl_FragData[1].xyz = vec3(1.0); \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected0 = 'layout(location = 0) out vec4 czm_out0;';
        var expected1 = 'layout(location = 1) out vec4 czm_out1;';
        expect(output).toContain(expected0);
        expect(output).toContain(expected1);
    });

    it('removes old functions/variables from fragment shader', function() {
        var old_fragment =
            '#define OUTPUT_DECLARATION \n' +
            '#extension GL_EXT_draw_buffers : enable \n' +
            'uniform sampler2D example; \n' +
            'uniform sampler2D exampleCube; \n' +
            'uniform sampler2D example3D; \n' +
            'varying vec2 v_textureCoordinates; \n' +
            'void main() \n' +
            '{ \n' +
            '    gl_FragData[0] = texture2D(example, v_textureCoordinates); \n' +
            '    gl_FragData[1] = textureCube(exampleCube, v_textureCoordinates); \n' +
            '    gl_FragData[2] = texture3D(example3D, v_textureCoordinates); \n' +
            '    gl_FragDepthEXT = 0.0; \n' +
            '} \n';

        var output = modernizeShader(old_fragment, true);

        var expectedDepth = 'gl_FragDepth = 0.0;';
        var expectedTexture2D = 'texture(example, v_textureCoordinates);';
        var expectedTextureCube = 'texture(exampleCube, v_textureCoordinates);';
        var expectedTexture3D = 'texture(example3D, v_textureCoordinates);';
        var expectedIn = 'in vec2 v_textureCoordinates;';

        var notExpectedDepth = 'gl_FragDepthEXT = 0.0;';
        var notExpectedTexture2D = 'texture2D(example, v_textureCoordinates);';
        var notExpectedTextureCube = 'textureCube(exampleCube, v_textureCoordinates);';
        var notExpectedTexture3D = 'texture3D(example3D, v_textureCoordinates);';
        var notExpectedVarying = 'varying vec2 v_textureCoordinates;';

        expect(output).toContain(expectedDepth);
        expect(output).toContain(expectedTexture2D);
        expect(output).toContain(expectedTextureCube);
        expect(output).toContain(expectedTexture3D);
        expect(output).toContain(expectedIn);

        expect(output).not.toContain(notExpectedDepth);
        expect(output).not.toContain(notExpectedTexture2D);
        expect(output).not.toContain(notExpectedTextureCube);
        expect(output).not.toContain(notExpectedTexture3D);
        expect(output).not.toContain(notExpectedVarying);
    });

    it('removes old functions/variables from vertex shader', function() {
        var old_vertex =
            '#define OUTPUT_DECLARATION \n' +
            'attribute vec4 position; \n' +
            'varying vec4 varyingVariable; \n' +
            'void main() \n' +
            '{ \n' +
            '    gl_Position = position; \n' +
            '    varyingVariable = position.wzyx; \n' +
            '} \n';

        var output = modernizeShader(old_vertex, false);

        var expectedOut = 'out vec4 varyingVariable;';
        var expectedIn = 'in vec4 position;';

        var notExpectedAttribute = 'attribute vec4 varyingVariable;';
        var notExpectedVarying = 'varying vec2 varyingVariable;';

        expect(output).toContain(expectedOut);
        expect(output).toContain(expectedIn);

        expect(output).not.toContain(notExpectedAttribute);
        expect(output).not.toContain(notExpectedVarying);
    });

    it('creates single layout qualifier under single branch, single condition', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        expect(output).toContain(expected);
    });

    it('creates multiple layout qualifiers under single branch, single condition', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    gl_FragData[1] = vec4(1.0); \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected0 = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        var expected1 = '#ifdef EXAMPLE_BRANCH \nlayout(location = 1) out vec4 czm_out1;\n#endif';
        expect(output).toContain(expected0);
        expect(output).toContain(expected1);
    });

    it('creates multiple layout qualifiers under multiple branches, single condition (cancels)', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    gl_FragData[1] = vec4(1.0); \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '    #ifndef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    gl_FragData[1] = vec4(1.0); \n' +
            '    #endif //!EXAMPLE_BRANCH \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var notExpected = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        expect(output).not.toContain(notExpected);
    });

    it('creates single layout qualifier under multiple branches, multiple conditions (cancels)', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            '#define EXAMPLE_BRANCH1 \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '    #ifdef EXAMPLE_BRANCH1 \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    #endif //EXAMPLE_BRANCH1 \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var notExpected = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        expect(output).not.toContain(notExpected);
    });

    it('creates multiple layout qualifiers under multiple branches, multiple conditions (cascades)', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            '#define EXAMPLE_BRANCH1 \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    #ifdef EXAMPLE_BRANCH1 \n' +
            '    gl_FragData[1] = vec4(1.0); \n' +
            '    #endif //EXAMPLE_BRANCH1 \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected0 = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        var expected1 = /#ifdef (EXAMPLE_BRANCH|EXAMPLE_BRANCH1)\s*\n\s*#ifdef (EXAMPLE_BRANCH1|EXAMPLE_BRANCH)\s*\n\s*layout\(location = 1\) out vec4 czm_out1;/g;
        var containsExpected0 = expected1.test(output);
        expect(output).toContain(expected0);
        expect(containsExpected0).toBe(true);
    });

    it('creates single layout qualifier under multiple branches, single condition (else)', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    #else \n' +
            '    gl_FragData[0] = vec4(1.0); \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var notExpected = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        expect(output).not.toContain(notExpected);
    });

    it('creates branched layout qualifiers for gl_FragColor and gl_FragData', function() {
        var noQualifiers =
            '#define OUTPUT_DECLARATION \n' +
            '#define EXAMPLE_BRANCH \n' +
            'void main() \n' +
            '{ \n' +
            '    #ifdef EXAMPLE_BRANCH \n' +
            '    gl_FragData[0] = vec4(0.0); \n' +
            '    #else \n' +
            '    gl_FragColor = vec4(1.0); \n' +
            '    #endif //EXAMPLE_BRANCH \n' +
            '} \n';
        var output = modernizeShader(noQualifiers, true);
        var expected0 = '#ifdef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_out0;\n#endif';
        var expected1 = '#ifndef EXAMPLE_BRANCH \nlayout(location = 0) out vec4 czm_fragColor;\n#endif';
        expect(output).toContain(expected0);
        expect(output).toContain(expected1);
    });
});