/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "WebGLContextUtils.h"
#include "WebGLContext.h"

#include "GLContext.h"
#include "jsapi.h"
#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/gfx/Logging.h"
#include "mozilla/Preferences.h"
#include "mozilla/Sprintf.h"
#include "nsIDOMEvent.h"
#include "nsIScriptSecurityManager.h"
#include "nsIVariant.h"
#include "nsPrintfCString.h"
#include "nsServiceManagerUtils.h"
#include <stdarg.h>
#include "WebGLBuffer.h"
#include "WebGLExtensions.h"
#include "WebGLFramebuffer.h"
#include "WebGLProgram.h"
#include "WebGLTexture.h"
#include "WebGLVertexArray.h"

namespace mozilla {

TexTarget
TexImageTargetToTexTarget(TexImageTarget texImageTarget)
{
    switch (texImageTarget.get()) {
    case LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_X:
    case LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_X:
    case LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_Y:
    case LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_Y:
    case LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_Z:
    case LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_Z:
        return LOCAL_GL_TEXTURE_CUBE_MAP;

    default:
        return texImageTarget.get();
    }
}

JS::Value
StringValue(JSContext* cx, const char* chars, ErrorResult& rv)
{
    JSString* str = JS_NewStringCopyZ(cx, chars);
    if (!str) {
        rv.Throw(NS_ERROR_OUT_OF_MEMORY);
        return JS::NullValue();
    }

    return JS::StringValue(str);
}

void
WebGLContext::GenerateWarning(const char* fmt, ...) const
{
    va_list ap;
    va_start(ap, fmt);

    GenerateWarning(fmt, ap);

    va_end(ap);
}

void
WebGLContext::GenerateWarning(const char* fmt, va_list ap) const
{
    if (!ShouldGenerateWarnings())
        return;

    mAlreadyGeneratedWarnings++;

    char buf[1024];
    VsprintfLiteral(buf, fmt, ap);

    // no need to print to stderr, as JS_ReportWarning takes care of this for us.

    if (!mCanvasElement) {
        return;
    }

    dom::AutoJSAPI api;
    if (!api.Init(mCanvasElement->OwnerDoc()->GetScopeObject())) {
        return;
    }

    JSContext* cx = api.cx();
    JS_ReportWarningASCII(cx, "WebGL warning: %s", buf);
    if (!ShouldGenerateWarnings()) {
        JS_ReportWarningASCII(cx,
                              "WebGL: No further warnings will be reported for"
                              " this WebGL context."
                              " (already reported %d warnings)",
                              mAlreadyGeneratedWarnings);
    }
}

bool
WebGLContext::ShouldGenerateWarnings() const
{
    if (mMaxWarnings == -1)
        return true;

    return mAlreadyGeneratedWarnings < mMaxWarnings;
}

void
WebGLContext::GeneratePerfWarning(const char* fmt, ...) const
{
    if (!ShouldGeneratePerfWarnings())
        return;

    if (!mCanvasElement)
        return;

    dom::AutoJSAPI api;
    if (!api.Init(mCanvasElement->OwnerDoc()->GetScopeObject()))
        return;
    JSContext* cx = api.cx();

    ////

    va_list ap;
    va_start(ap, fmt);

    char buf[1024];
    VsprintfLiteral(buf, fmt, ap);

    va_end(ap);

    ////

    JS_ReportWarningASCII(cx, "WebGL perf warning: %s", buf);
    mNumPerfWarnings++;

    if (!ShouldGeneratePerfWarnings()) {
        JS_ReportWarningASCII(cx,
                              "WebGL: After reporting %u, no further perf warnings will"
                              " be reported for this WebGL context.",
                              uint32_t(mNumPerfWarnings));
    }
}

void
WebGLContext::SynthesizeGLError(GLenum err) const
{
    /* ES2 section 2.5 "GL Errors" states that implementations can have
     * multiple 'flags', as errors might be caught in different parts of
     * a distributed implementation.
     * We're signing up as a distributed implementation here, with
     * separate flags for WebGL and the underlying GLContext.
     */
    if (!mWebGLError)
        mWebGLError = err;
}

void
WebGLContext::SynthesizeGLError(GLenum err, const char* fmt, ...) const
{
    va_list va;
    va_start(va, fmt);
    GenerateWarning(fmt, va);
    va_end(va);

    return SynthesizeGLError(err);
}

void
WebGLContext::ErrorInvalidEnum(const char* fmt, ...) const
{
    va_list va;
    va_start(va, fmt);
    GenerateWarning(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_ENUM);
}

void
WebGLContext::ErrorInvalidEnumInfo(const char* info, GLenum enumValue) const
{
    nsCString name;
    EnumName(enumValue, &name);

    return ErrorInvalidEnum("%s: invalid enum value %s", info, name.BeginReading());
}

void
WebGLContext::ErrorInvalidEnumInfo(const char* info, const char* funcName,
                                   GLenum enumValue) const
{
    nsCString name;
    EnumName(enumValue, &name);

    ErrorInvalidEnum("%s: %s: Invalid enum: 0x%04x (%s).", funcName, info,
                     enumValue, name.BeginReading());
}

void
WebGLContext::ErrorInvalidOperation(const char* fmt, ...) const
{
    va_list va;
    va_start(va, fmt);
    GenerateWarning(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_OPERATION);
}

void
WebGLContext::ErrorInvalidValue(const char* fmt, ...) const
{
    va_list va;
    va_start(va, fmt);
    GenerateWarning(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_VALUE);
}

void
WebGLContext::ErrorInvalidFramebufferOperation(const char* fmt, ...) const
{
    va_list va;
    va_start(va, fmt);
    GenerateWarning(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_INVALID_FRAMEBUFFER_OPERATION);
}

void
WebGLContext::ErrorOutOfMemory(const char* fmt, ...) const
{
    va_list va;
    va_start(va, fmt);
    GenerateWarning(fmt, va);
    va_end(va);

    return SynthesizeGLError(LOCAL_GL_OUT_OF_MEMORY);
}

void
WebGLContext::ErrorImplementationBug(const char* fmt, ...) const
{
    const nsPrintfCString warning("Implementation bug, please file at %s! %s",
                                  "https://bugzilla.mozilla.org/", fmt);

    va_list va;
    va_start(va, fmt);
    GenerateWarning(warning.BeginReading(), va);
    va_end(va);

    MOZ_ASSERT(false, "WebGLContext::ErrorImplementationBug");
    NS_ERROR("WebGLContext::ErrorImplementationBug");
    return SynthesizeGLError(LOCAL_GL_OUT_OF_MEMORY);
}

/*static*/ const char*
WebGLContext::ErrorName(GLenum error)
{
    switch(error) {
    case LOCAL_GL_INVALID_ENUM:
        return "INVALID_ENUM";
    case LOCAL_GL_INVALID_OPERATION:
        return "INVALID_OPERATION";
    case LOCAL_GL_INVALID_VALUE:
        return "INVALID_VALUE";
    case LOCAL_GL_OUT_OF_MEMORY:
        return "OUT_OF_MEMORY";
    case LOCAL_GL_INVALID_FRAMEBUFFER_OPERATION:
        return "INVALID_FRAMEBUFFER_OPERATION";
    case LOCAL_GL_NO_ERROR:
        return "NO_ERROR";
    default:
        MOZ_ASSERT(false);
        return "[unknown WebGL error]";
    }
}

// This version is fallible and will return nullptr if unrecognized.
static const char*
GetEnumName(GLenum val)
{
    switch (val) {
#define XX(x) case LOCAL_GL_##x: return #x
        XX(NONE);
        XX(ALPHA);
        XX(ATC_RGB);
        XX(ATC_RGBA_EXPLICIT_ALPHA);
        XX(ATC_RGBA_INTERPOLATED_ALPHA);
        XX(COMPRESSED_RGBA_PVRTC_2BPPV1);
        XX(COMPRESSED_RGBA_PVRTC_4BPPV1);
        XX(COMPRESSED_RGBA_S3TC_DXT1_EXT);
        XX(COMPRESSED_RGBA_S3TC_DXT3_EXT);
        XX(COMPRESSED_RGBA_S3TC_DXT5_EXT);
        XX(COMPRESSED_RGB_PVRTC_2BPPV1);
        XX(COMPRESSED_RGB_PVRTC_4BPPV1);
        XX(COMPRESSED_RGB_S3TC_DXT1_EXT);
        XX(DEPTH_ATTACHMENT);
        XX(DEPTH_COMPONENT);
        XX(DEPTH_COMPONENT16);
        XX(DEPTH_COMPONENT32);
        XX(DEPTH_STENCIL);
        XX(DEPTH24_STENCIL8);
        XX(DRAW_FRAMEBUFFER);
        XX(ETC1_RGB8_OES);
        XX(FLOAT);
        XX(INT);
        XX(FRAMEBUFFER);
        XX(HALF_FLOAT);
        XX(LUMINANCE);
        XX(LUMINANCE_ALPHA);
        XX(READ_FRAMEBUFFER);
        XX(RGB);
        XX(RGB16F);
        XX(RGB32F);
        XX(RGBA);
        XX(RGBA16F);
        XX(RGBA32F);
        XX(SRGB);
        XX(SRGB_ALPHA);
        XX(TEXTURE_2D);
        XX(TEXTURE_3D);
        XX(TEXTURE_CUBE_MAP);
        XX(TEXTURE_CUBE_MAP_NEGATIVE_X);
        XX(TEXTURE_CUBE_MAP_NEGATIVE_Y);
        XX(TEXTURE_CUBE_MAP_NEGATIVE_Z);
        XX(TEXTURE_CUBE_MAP_POSITIVE_X);
        XX(TEXTURE_CUBE_MAP_POSITIVE_Y);
        XX(TEXTURE_CUBE_MAP_POSITIVE_Z);
        XX(UNSIGNED_BYTE);
        XX(UNSIGNED_INT);
        XX(UNSIGNED_INT_24_8);
        XX(UNSIGNED_SHORT);
        XX(UNSIGNED_SHORT_4_4_4_4);
        XX(UNSIGNED_SHORT_5_5_5_1);
        XX(UNSIGNED_SHORT_5_6_5);
        XX(READ_BUFFER);
        XX(UNPACK_ROW_LENGTH);
        XX(UNPACK_SKIP_ROWS);
        XX(UNPACK_SKIP_PIXELS);
        XX(PACK_ROW_LENGTH);
        XX(PACK_SKIP_ROWS);
        XX(PACK_SKIP_PIXELS);
        XX(COLOR);
        XX(DEPTH);
        XX(STENCIL);
        XX(RED);
        XX(RGB8);
        XX(RGBA8);
        XX(RGB10_A2);
        XX(TEXTURE_BINDING_3D);
        XX(UNPACK_SKIP_IMAGES);
        XX(UNPACK_IMAGE_HEIGHT);
        XX(TEXTURE_WRAP_R);
        XX(MAX_3D_TEXTURE_SIZE);
        XX(UNSIGNED_INT_2_10_10_10_REV);
        XX(MAX_ELEMENTS_VERTICES);
        XX(MAX_ELEMENTS_INDICES);
        XX(TEXTURE_MIN_LOD);
        XX(TEXTURE_MAX_LOD);
        XX(TEXTURE_BASE_LEVEL);
        XX(TEXTURE_MAX_LEVEL);
        XX(MIN);
        XX(MAX);
        XX(DEPTH_COMPONENT24);
        XX(MAX_TEXTURE_LOD_BIAS);
        XX(TEXTURE_COMPARE_MODE);
        XX(TEXTURE_COMPARE_FUNC);
        XX(CURRENT_QUERY);
        XX(QUERY_RESULT);
        XX(QUERY_RESULT_AVAILABLE);
        XX(STREAM_READ);
        XX(STREAM_COPY);
        XX(STATIC_READ);
        XX(STATIC_COPY);
        XX(DYNAMIC_READ);
        XX(DYNAMIC_COPY);
        XX(MAX_DRAW_BUFFERS);
        XX(DRAW_BUFFER0);
        XX(DRAW_BUFFER1);
        XX(DRAW_BUFFER2);
        XX(DRAW_BUFFER3);
        XX(DRAW_BUFFER4);
        XX(DRAW_BUFFER5);
        XX(DRAW_BUFFER6);
        XX(DRAW_BUFFER7);
        XX(DRAW_BUFFER8);
        XX(DRAW_BUFFER9);
        XX(DRAW_BUFFER10);
        XX(DRAW_BUFFER11);
        XX(DRAW_BUFFER12);
        XX(DRAW_BUFFER13);
        XX(DRAW_BUFFER14);
        XX(DRAW_BUFFER15);
        XX(MAX_FRAGMENT_UNIFORM_COMPONENTS);
        XX(MAX_VERTEX_UNIFORM_COMPONENTS);
        XX(SAMPLER_3D);
        XX(SAMPLER_2D_SHADOW);
        XX(FRAGMENT_SHADER_DERIVATIVE_HINT);
        XX(PIXEL_PACK_BUFFER);
        XX(PIXEL_UNPACK_BUFFER);
        XX(PIXEL_PACK_BUFFER_BINDING);
        XX(PIXEL_UNPACK_BUFFER_BINDING);
        XX(FLOAT_MAT2x3);
        XX(FLOAT_MAT2x4);
        XX(FLOAT_MAT3x2);
        XX(FLOAT_MAT3x4);
        XX(FLOAT_MAT4x2);
        XX(FLOAT_MAT4x3);
        XX(SRGB8);
        XX(SRGB8_ALPHA8);
        XX(COMPARE_REF_TO_TEXTURE);
        XX(VERTEX_ATTRIB_ARRAY_INTEGER);
        XX(MAX_ARRAY_TEXTURE_LAYERS);
        XX(MIN_PROGRAM_TEXEL_OFFSET);
        XX(MAX_PROGRAM_TEXEL_OFFSET);
        XX(MAX_VARYING_COMPONENTS);
        XX(TEXTURE_2D_ARRAY);
        XX(TEXTURE_BINDING_2D_ARRAY);
        XX(R11F_G11F_B10F);
        XX(UNSIGNED_INT_10F_11F_11F_REV);
        XX(RGB9_E5);
        XX(UNSIGNED_INT_5_9_9_9_REV);
        XX(TRANSFORM_FEEDBACK_BUFFER_MODE);
        XX(MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS);
        XX(TRANSFORM_FEEDBACK_VARYINGS);
        XX(TRANSFORM_FEEDBACK_BUFFER_START);
        XX(TRANSFORM_FEEDBACK_BUFFER_SIZE);
        XX(TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN);
        XX(RASTERIZER_DISCARD);
        XX(MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS);
        XX(MAX_TRANSFORM_FEEDBACK_SEPARATE_ATTRIBS);
        XX(INTERLEAVED_ATTRIBS);
        XX(SEPARATE_ATTRIBS);
        XX(TRANSFORM_FEEDBACK_BUFFER);
        XX(TRANSFORM_FEEDBACK_BUFFER_BINDING);
        XX(RGBA32UI);
        XX(RGB32UI);
        XX(RGBA16UI);
        XX(RGB16UI);
        XX(RGBA8UI);
        XX(RGB8UI);
        XX(RGBA32I);
        XX(RGB32I);
        XX(RGBA16I);
        XX(RGB16I);
        XX(RGBA8I);
        XX(RGB8I);
        XX(RED_INTEGER);
        XX(RGB_INTEGER);
        XX(RGBA_INTEGER);
        XX(SAMPLER_2D_ARRAY);
        XX(SAMPLER_2D_ARRAY_SHADOW);
        XX(SAMPLER_CUBE_SHADOW);
        XX(UNSIGNED_INT_VEC2);
        XX(UNSIGNED_INT_VEC3);
        XX(UNSIGNED_INT_VEC4);
        XX(INT_SAMPLER_2D);
        XX(INT_SAMPLER_3D);
        XX(INT_SAMPLER_CUBE);
        XX(INT_SAMPLER_2D_ARRAY);
        XX(UNSIGNED_INT_SAMPLER_2D);
        XX(UNSIGNED_INT_SAMPLER_3D);
        XX(UNSIGNED_INT_SAMPLER_CUBE);
        XX(UNSIGNED_INT_SAMPLER_2D_ARRAY);
        XX(DEPTH_COMPONENT32F);
        XX(DEPTH32F_STENCIL8);
        XX(FLOAT_32_UNSIGNED_INT_24_8_REV);
        XX(FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING);
        XX(FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE);
        XX(FRAMEBUFFER_ATTACHMENT_RED_SIZE);
        XX(FRAMEBUFFER_ATTACHMENT_GREEN_SIZE);
        XX(FRAMEBUFFER_ATTACHMENT_BLUE_SIZE);
        XX(FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE);
        XX(FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE);
        XX(FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE);
        XX(FRAMEBUFFER_DEFAULT);
        XX(DEPTH_STENCIL_ATTACHMENT);
        XX(UNSIGNED_NORMALIZED);
        XX(DRAW_FRAMEBUFFER_BINDING);
        XX(READ_FRAMEBUFFER_BINDING);
        XX(RENDERBUFFER_SAMPLES);
        XX(FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER);
        XX(MAX_COLOR_ATTACHMENTS);
        XX(COLOR_ATTACHMENT0);
        XX(COLOR_ATTACHMENT1);
        XX(COLOR_ATTACHMENT2);
        XX(COLOR_ATTACHMENT3);
        XX(COLOR_ATTACHMENT4);
        XX(COLOR_ATTACHMENT5);
        XX(COLOR_ATTACHMENT6);
        XX(COLOR_ATTACHMENT7);
        XX(COLOR_ATTACHMENT8);
        XX(COLOR_ATTACHMENT9);
        XX(COLOR_ATTACHMENT10);
        XX(COLOR_ATTACHMENT11);
        XX(COLOR_ATTACHMENT12);
        XX(COLOR_ATTACHMENT13);
        XX(COLOR_ATTACHMENT14);
        XX(COLOR_ATTACHMENT15);
        XX(FRAMEBUFFER_INCOMPLETE_MULTISAMPLE);
        XX(MAX_SAMPLES);
        XX(RG);
        XX(RG_INTEGER);
        XX(R8);
        XX(RG8);
        XX(R16F);
        XX(R32F);
        XX(RG16F);
        XX(RG32F);
        XX(R8I);
        XX(R8UI);
        XX(R16I);
        XX(R16UI);
        XX(R32I);
        XX(R32UI);
        XX(RG8I);
        XX(RG8UI);
        XX(RG16I);
        XX(RG16UI);
        XX(RG32I);
        XX(RG32UI);
        XX(VERTEX_ARRAY_BINDING);
        XX(R8_SNORM);
        XX(RG8_SNORM);
        XX(RGB8_SNORM);
        XX(RGBA8_SNORM);
        XX(SIGNED_NORMALIZED);
        XX(PRIMITIVE_RESTART_FIXED_INDEX);
        XX(COPY_READ_BUFFER);
        XX(COPY_WRITE_BUFFER);
        XX(UNIFORM_BUFFER);
        XX(UNIFORM_BUFFER_BINDING);
        XX(UNIFORM_BUFFER_START);
        XX(UNIFORM_BUFFER_SIZE);
        XX(MAX_VERTEX_UNIFORM_BLOCKS);
        XX(MAX_FRAGMENT_UNIFORM_BLOCKS);
        XX(MAX_COMBINED_UNIFORM_BLOCKS);
        XX(MAX_UNIFORM_BUFFER_BINDINGS);
        XX(MAX_UNIFORM_BLOCK_SIZE);
        XX(MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS);
        XX(MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS);
        XX(UNIFORM_BUFFER_OFFSET_ALIGNMENT);
        XX(ACTIVE_UNIFORM_BLOCKS);
        XX(UNIFORM_TYPE);
        XX(UNIFORM_SIZE);
        XX(UNIFORM_BLOCK_INDEX);
        XX(UNIFORM_OFFSET);
        XX(UNIFORM_ARRAY_STRIDE);
        XX(UNIFORM_MATRIX_STRIDE);
        XX(UNIFORM_IS_ROW_MAJOR);
        XX(UNIFORM_BLOCK_BINDING);
        XX(UNIFORM_BLOCK_DATA_SIZE);
        XX(UNIFORM_BLOCK_ACTIVE_UNIFORMS);
        XX(UNIFORM_BLOCK_ACTIVE_UNIFORM_INDICES);
        XX(UNIFORM_BLOCK_REFERENCED_BY_VERTEX_SHADER);
        XX(UNIFORM_BLOCK_REFERENCED_BY_FRAGMENT_SHADER);
        XX(MAX_VERTEX_OUTPUT_COMPONENTS);
        XX(MAX_FRAGMENT_INPUT_COMPONENTS);
        XX(MAX_SERVER_WAIT_TIMEOUT);
        XX(OBJECT_TYPE);
        XX(SYNC_CONDITION);
        XX(SYNC_STATUS);
        XX(SYNC_FLAGS);
        XX(SYNC_FENCE);
        XX(SYNC_GPU_COMMANDS_COMPLETE);
        XX(UNSIGNALED);
        XX(SIGNALED);
        XX(ALREADY_SIGNALED);
        XX(TIMEOUT_EXPIRED);
        XX(CONDITION_SATISFIED);
        XX(WAIT_FAILED);
        XX(VERTEX_ATTRIB_ARRAY_DIVISOR);
        XX(ANY_SAMPLES_PASSED);
        XX(ANY_SAMPLES_PASSED_CONSERVATIVE);
        XX(SAMPLER_BINDING);
        XX(RGB10_A2UI);
        XX(TEXTURE_SWIZZLE_R);
        XX(TEXTURE_SWIZZLE_G);
        XX(TEXTURE_SWIZZLE_B);
        XX(TEXTURE_SWIZZLE_A);
        XX(GREEN);
        XX(BLUE);
        XX(INT_2_10_10_10_REV);
        XX(TRANSFORM_FEEDBACK);
        XX(TRANSFORM_FEEDBACK_PAUSED);
        XX(TRANSFORM_FEEDBACK_ACTIVE);
        XX(TRANSFORM_FEEDBACK_BINDING);
        XX(COMPRESSED_R11_EAC);
        XX(COMPRESSED_SIGNED_R11_EAC);
        XX(COMPRESSED_RG11_EAC);
        XX(COMPRESSED_SIGNED_RG11_EAC);
        XX(COMPRESSED_RGB8_ETC2);
        XX(COMPRESSED_SRGB8_ETC2);
        XX(COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2);
        XX(COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2);
        XX(COMPRESSED_RGBA8_ETC2_EAC);
        XX(COMPRESSED_SRGB8_ALPHA8_ETC2_EAC);
        XX(TEXTURE_IMMUTABLE_FORMAT);
        XX(MAX_ELEMENT_INDEX);
        XX(NUM_SAMPLE_COUNTS);
        XX(TEXTURE_IMMUTABLE_LEVELS);
#undef XX
    }

    return nullptr;
}

/*static*/ void
WebGLContext::EnumName(GLenum val, nsCString* out_name)
{
    const char* name = GetEnumName(val);
    if (name) {
        *out_name = name;
        return;
    }

    *out_name = nsPrintfCString("<enum 0x%04x>", val);
}

void
WebGLContext::ErrorInvalidEnumArg(const char* funcName, const char* argName,
                                  GLenum val) const
{
    nsCString enumName;
    EnumName(val, &enumName);
    ErrorInvalidEnum("%s: Bad `%s`: %s", funcName, argName, enumName.BeginReading());
}

bool
IsCompressedTextureFormat(GLenum format)
{
    switch (format) {
    case LOCAL_GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
    case LOCAL_GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
    case LOCAL_GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
    case LOCAL_GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
    case LOCAL_GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
    case LOCAL_GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
    case LOCAL_GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
    case LOCAL_GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
    case LOCAL_GL_ATC_RGB:
    case LOCAL_GL_ATC_RGBA_EXPLICIT_ALPHA:
    case LOCAL_GL_ATC_RGBA_INTERPOLATED_ALPHA:
    case LOCAL_GL_COMPRESSED_RGB_PVRTC_4BPPV1:
    case LOCAL_GL_COMPRESSED_RGB_PVRTC_2BPPV1:
    case LOCAL_GL_COMPRESSED_RGBA_PVRTC_4BPPV1:
    case LOCAL_GL_COMPRESSED_RGBA_PVRTC_2BPPV1:
    case LOCAL_GL_ETC1_RGB8_OES:
    case LOCAL_GL_COMPRESSED_R11_EAC:
    case LOCAL_GL_COMPRESSED_SIGNED_R11_EAC:
    case LOCAL_GL_COMPRESSED_RG11_EAC:
    case LOCAL_GL_COMPRESSED_SIGNED_RG11_EAC:
    case LOCAL_GL_COMPRESSED_RGB8_ETC2:
    case LOCAL_GL_COMPRESSED_SRGB8_ETC2:
    case LOCAL_GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2:
    case LOCAL_GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2:
    case LOCAL_GL_COMPRESSED_RGBA8_ETC2_EAC:
    case LOCAL_GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC:
        return true;
    default:
        return false;
    }
}


bool
IsTextureFormatCompressed(TexInternalFormat format)
{
    return IsCompressedTextureFormat(format.get());
}

GLenum
WebGLContext::GetAndFlushUnderlyingGLErrors() const
{
    // Get and clear GL error in ALL cases.
    GLenum error = gl->fGetError();

    // Only store in mUnderlyingGLError if is hasn't already recorded an
    // error.
    if (!mUnderlyingGLError)
        mUnderlyingGLError = error;

    return error;
}

#ifdef DEBUG
// For NaNs, etc.
static bool
IsCacheCorrect(float cached, float actual)
{
    if (IsNaN(cached)) {
        // GL is allowed to do anything it wants for NaNs, so if we're shadowing
        // a NaN, then whatever `actual` is might be correct.
        return true;
    }

    return cached == actual;
}

void
AssertUintParamCorrect(gl::GLContext* gl, GLenum pname, GLuint shadow)
{
    GLuint val = 0;
    gl->GetUIntegerv(pname, &val);
    if (val != shadow) {
      printf_stderr("Failed 0x%04x shadow: Cached 0x%x/%u, should be 0x%x/%u.\n",
                    pname, shadow, shadow, val, val);
      MOZ_ASSERT(false, "Bad cached value.");
    }
}

void
AssertMaskedUintParamCorrect(gl::GLContext* gl, GLenum pname, GLuint mask,
                             GLuint shadow)
{
    GLuint val = 0;
    gl->GetUIntegerv(pname, &val);

    const GLuint valMasked = val & mask;
    const GLuint shadowMasked = shadow & mask;

    if (valMasked != shadowMasked) {
      printf_stderr("Failed 0x%04x shadow: Cached 0x%x/%u, should be 0x%x/%u.\n",
                    pname, shadowMasked, shadowMasked, valMasked, valMasked);
      MOZ_ASSERT(false, "Bad cached value.");
    }
}
#else
void
AssertUintParamCorrect(gl::GLContext*, GLenum, GLuint)
{
}
#endif

void
WebGLContext::AssertCachedBindings() const
{
#ifdef DEBUG
    GetAndFlushUnderlyingGLErrors();

    if (IsWebGL2() || IsExtensionEnabled(WebGLExtensionID::OES_vertex_array_object)) {
        GLuint bound = mBoundVertexArray ? mBoundVertexArray->GLName() : 0;
        AssertUintParamCorrect(gl, LOCAL_GL_VERTEX_ARRAY_BINDING, bound);
    }

    GLint stencilBits = 0;
    if (GetStencilBits(&stencilBits)) { // Depends on current draw framebuffer.
        const GLuint stencilRefMask = (1 << stencilBits) - 1;

        AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_REF,      stencilRefMask, mStencilRefFront);
        AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_BACK_REF, stencilRefMask, mStencilRefBack);
    }

    // Program
    GLuint bound = mCurrentProgram ? mCurrentProgram->mGLName : 0;
    AssertUintParamCorrect(gl, LOCAL_GL_CURRENT_PROGRAM, bound);

    // Textures
    GLenum activeTexture = mActiveTexture + LOCAL_GL_TEXTURE0;
    AssertUintParamCorrect(gl, LOCAL_GL_ACTIVE_TEXTURE, activeTexture);

    WebGLTexture* curTex = ActiveBoundTextureForTarget(LOCAL_GL_TEXTURE_2D);
    bound = curTex ? curTex->mGLName : 0;
    AssertUintParamCorrect(gl, LOCAL_GL_TEXTURE_BINDING_2D, bound);

    curTex = ActiveBoundTextureForTarget(LOCAL_GL_TEXTURE_CUBE_MAP);
    bound = curTex ? curTex->mGLName : 0;
    AssertUintParamCorrect(gl, LOCAL_GL_TEXTURE_BINDING_CUBE_MAP, bound);

    // Buffers
    bound = mBoundArrayBuffer ? mBoundArrayBuffer->mGLName : 0;
    AssertUintParamCorrect(gl, LOCAL_GL_ARRAY_BUFFER_BINDING, bound);

    MOZ_ASSERT(mBoundVertexArray);
    WebGLBuffer* curBuff = mBoundVertexArray->mElementArrayBuffer;
    bound = curBuff ? curBuff->mGLName : 0;
    AssertUintParamCorrect(gl, LOCAL_GL_ELEMENT_ARRAY_BUFFER_BINDING, bound);

    MOZ_ASSERT(!GetAndFlushUnderlyingGLErrors());
#endif

    // We do not check the renderbuffer binding, because we never rely on it matching.
}

void
WebGLContext::AssertCachedGlobalState() const
{
#ifdef DEBUG
    GetAndFlushUnderlyingGLErrors();

    ////////////////

    // Draw state
    MOZ_ASSERT(gl->fIsEnabled(LOCAL_GL_DITHER) == mDitherEnabled);
    MOZ_ASSERT_IF(IsWebGL2(),
                  gl->fIsEnabled(LOCAL_GL_RASTERIZER_DISCARD) == mRasterizerDiscardEnabled);
    MOZ_ASSERT(gl->fIsEnabled(LOCAL_GL_SCISSOR_TEST) == mScissorTestEnabled);

    // Cannot trivially check COLOR_CLEAR_VALUE, since in old GL versions glGet may clamp
    // based on whether the current framebuffer is floating-point or not.
    // This also means COLOR_CLEAR_VALUE save+restore is dangerous!

    realGLboolean depthWriteMask = 0;
    gl->fGetBooleanv(LOCAL_GL_DEPTH_WRITEMASK, &depthWriteMask);
    MOZ_ASSERT(depthWriteMask == mDepthWriteMask);

    GLfloat depthClearValue = 0.0f;
    gl->fGetFloatv(LOCAL_GL_DEPTH_CLEAR_VALUE, &depthClearValue);
    MOZ_ASSERT(IsCacheCorrect(mDepthClearValue, depthClearValue));

    const int maxStencilBits = 8;
    const GLuint maxStencilBitsMask = (1 << maxStencilBits) - 1;
    AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_CLEAR_VALUE, maxStencilBitsMask, mStencilClearValue);

    // GLES 3.0.4, $4.1.4, p177:
    //   [...] the front and back stencil mask are both set to the value `2^s - 1`, where
    //   `s` is greater than or equal to the number of bits in the deepest stencil buffer
    //   supported by the GL implementation.
    AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_VALUE_MASK,      maxStencilBitsMask, mStencilValueMaskFront);
    AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_BACK_VALUE_MASK, maxStencilBitsMask, mStencilValueMaskBack);

    AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_WRITEMASK,       maxStencilBitsMask, mStencilWriteMaskFront);
    AssertMaskedUintParamCorrect(gl, LOCAL_GL_STENCIL_BACK_WRITEMASK,  maxStencilBitsMask, mStencilWriteMaskBack);

    // Viewport
    GLint int4[4] = {0, 0, 0, 0};
    gl->fGetIntegerv(LOCAL_GL_VIEWPORT, int4);
    MOZ_ASSERT(int4[0] == mViewportX &&
               int4[1] == mViewportY &&
               int4[2] == mViewportWidth &&
               int4[3] == mViewportHeight);

    AssertUintParamCorrect(gl, LOCAL_GL_PACK_ALIGNMENT, mPixelStore_PackAlignment);
    AssertUintParamCorrect(gl, LOCAL_GL_UNPACK_ALIGNMENT, mPixelStore_UnpackAlignment);

    if (IsWebGL2()) {
        AssertUintParamCorrect(gl, LOCAL_GL_UNPACK_IMAGE_HEIGHT, mPixelStore_UnpackImageHeight);
        AssertUintParamCorrect(gl, LOCAL_GL_UNPACK_SKIP_IMAGES , mPixelStore_UnpackSkipImages);
        AssertUintParamCorrect(gl, LOCAL_GL_UNPACK_ROW_LENGTH  , mPixelStore_UnpackRowLength);
        AssertUintParamCorrect(gl, LOCAL_GL_UNPACK_SKIP_ROWS   , mPixelStore_UnpackSkipRows);
        AssertUintParamCorrect(gl, LOCAL_GL_UNPACK_SKIP_PIXELS , mPixelStore_UnpackSkipPixels);
        AssertUintParamCorrect(gl, LOCAL_GL_PACK_ROW_LENGTH    , mPixelStore_PackRowLength);
        AssertUintParamCorrect(gl, LOCAL_GL_PACK_SKIP_ROWS     , mPixelStore_PackSkipRows);
        AssertUintParamCorrect(gl, LOCAL_GL_PACK_SKIP_PIXELS   , mPixelStore_PackSkipPixels);
    }

    MOZ_ASSERT(!GetAndFlushUnderlyingGLErrors());
#endif
}

const char*
InfoFrom(WebGLTexImageFunc func, WebGLTexDimensions dims)
{
    switch (dims) {
    case WebGLTexDimensions::Tex2D:
        switch (func) {
        case WebGLTexImageFunc::TexImage:        return "texImage2D";
        case WebGLTexImageFunc::TexSubImage:     return "texSubImage2D";
        case WebGLTexImageFunc::CopyTexImage:    return "copyTexImage2D";
        case WebGLTexImageFunc::CopyTexSubImage: return "copyTexSubImage2D";
        case WebGLTexImageFunc::CompTexImage:    return "compressedTexImage2D";
        case WebGLTexImageFunc::CompTexSubImage: return "compressedTexSubImage2D";
        default:
            MOZ_CRASH("GFX: invalid 2D TexDimensions");
        }
    case WebGLTexDimensions::Tex3D:
        switch (func) {
        case WebGLTexImageFunc::TexImage:        return "texImage3D";
        case WebGLTexImageFunc::TexSubImage:     return "texSubImage3D";
        case WebGLTexImageFunc::CopyTexSubImage: return "copyTexSubImage3D";
        case WebGLTexImageFunc::CompTexSubImage: return "compressedTexSubImage3D";
        default:
            MOZ_CRASH("GFX: invalid 3D TexDimensions");
        }
    default:
        MOZ_CRASH("GFX: invalid TexDimensions");
    }
}

////

JS::Value
StringValue(JSContext* cx, const nsAString& str, ErrorResult& er)
{
    JSString* jsStr = JS_NewUCStringCopyN(cx, str.BeginReading(), str.Length());
    if (!jsStr) {
        er.Throw(NS_ERROR_OUT_OF_MEMORY);
        return JS::NullValue();
    }

    return JS::StringValue(jsStr);
}

} // namespace mozilla
