// Copyright 2019 The Chromium Authors

// This proto description is adapted from the one used in clang-proto-fuzzer.

syntax = "proto2";
package fuzzing;

// TODO(nedwill): fuzz the following features
// function prototypes
// (in)variance
// structs
// interface blocks
// swizzles
// all ternary operators
// switch/case statements
// loops
// branches (case, break, continue, return, kill)
// preprocessor directives

enum Var {
  VAR_0 = 0;
  VAR_1 = 1;
  VAR_2 = 2;
  VAR_3 = 3;
}

message Lvalue {
  optional Var var = 1;
}

message Vec2 {
  optional float first = 1;
  optional float second = 2;
}

message Vec3 {
  optional float first = 1;
  optional float second = 2;
  optional float third = 3;
}

message Vec4 {
  optional float first = 1;
  optional float second = 2;
  optional float third = 3;
  optional float fourth = 4;
}

// Keep this in sync with `message Const`
enum Type {
  // Use suffix to avoid clashing with VOID define on Windows
  VOID_TYPE = 0;
  INT = 1;
  BOOL = 2;
  UINT = 3;
  FLOAT = 4;
  DOUBLE = 5;
  VEC2 = 6;
  VEC3 = 7;
  VEC4 = 8;
  BVEC2 = 9;
  BVEC3 = 10;
  BVEC4 = 11;
  IVEC2 = 12;
  IVEC3 = 13;
  IVEC4 = 14;
  UVEC2 = 15;
  UVEC3 = 16;
  UVEC4 = 17;
  MAT2 = 18;
  MAT3 = 19;
  MAT4 = 20;
  MAT2X2 = 21;
  MAT2X3 = 22;
  MAT2X4 = 23;
  MAT3X2 = 24;
  MAT3X3 = 25;
  MAT3X4 = 26;
  MAT4X2 = 27;
  MAT4X3 = 28;
  MAT4X4 = 29;
  // TODO(nedwill): support DVEC*, DMAT*
}

message Const {
  // Keep this in sync with `enum Type`
  oneof value {
    // Empty case is void
    int32 int32 = 1;
    bool boolean = 2;
    uint32 uint = 3;
    float float_const = 4;
    double double_const = 5;
    Vec2 vec2 = 6;
    Vec3 vec3 = 7;
    Vec4 vec4 = 8;
    Bvec2 bvec2 = 9;
    Bvec3 bvec3 = 10;
    Bvec4 bvec4 = 11;
    Ivec2 ivec2 = 12;
    Ivec3 ivec3 = 13;
    Ivec4 ivec4 = 14;
    Uvec2 uvec2 = 15;
    Uvec3 uvec3 = 16;
    Uvec4 uvec4 = 17;
    Mat2 mat2 = 18;
    Mat3 mat3 = 19;
    Mat4 mat4 = 20;
    Mat2 mat2x2 = 21;
    Mat2x3 mat2x3 = 22;
    Mat2x4 mat2x4 = 23;
    Mat3x2 mat3x2 = 24;
    Mat3 mat3x3 = 25;
    Mat3x4 mat3x4 = 26;
    Mat4x2 mat4x2 = 27;
    Mat4x3 mat4x3 = 28;
    Mat4 mat4x4 = 29;
    // TODO(nedwill): support DVEC*, DMAT*
  }
}

message Mat2x3 {
  optional Vec3 first = 1;
  optional Vec3 second = 2;
}

message Mat2x4 {
  optional Vec4 first = 1;
  optional Vec4 second = 2;
}

message Mat3x2 {
  optional Vec2 first = 1;
  optional Vec2 second = 2;
  optional Vec3 third = 3;
}

message Mat3x4 {
  optional Vec4 first = 1;
  optional Vec4 second = 2;
  optional Vec4 third = 3;
}

message Mat4x2 {
  optional Vec2 first = 1;
  optional Vec2 second = 2;
  optional Vec2 third = 3;
  optional Vec2 fourth = 4;
}

message Mat4x3 {
  optional Vec3 first = 1;
  optional Vec3 second = 2;
  optional Vec3 third = 3;
  optional Vec3 fourth = 4;
}

message Bvec2 {
  optional bool first = 1;
  optional bool second = 2;
}

message Bvec3 {
  optional bool first = 1;
  optional bool second = 2;
  optional bool third = 3;
}

message Bvec4 {
  optional bool first = 1;
  optional bool second = 2;
  optional bool third = 3;
  optional bool fourth = 4;
}

message Ivec2 {
  optional int32 first = 1;
  optional int32 second = 2;
}

message Ivec3 {
  optional int32 first = 1;
  optional int32 second = 2;
  optional int32 third = 3;
}

message Ivec4 {
  optional int32 first = 1;
  optional int32 second = 2;
  optional int32 third = 3;
  optional int32 fourth = 4;
}

message Uvec2 {
  optional uint32 first = 1;
  optional uint32 second = 2;
}

message Uvec3 {
  optional uint32 first = 1;
  optional uint32 second = 2;
  optional uint32 third = 3;
}

message Uvec4 {
  optional uint32 first = 1;
  optional uint32 second = 2;
  optional uint32 third = 3;
  optional uint32 fourth = 4;
}

message Mat2 {
  optional Vec2 first = 1;
  optional Vec2 second = 2;
}

message Mat3 {
  optional Vec3 first = 1;
  optional Vec3 second = 2;
  optional Vec3 third = 3;
}

message Mat4 {
  optional Vec4 first = 1;
  optional Vec4 second = 2;
  optional Vec4 third = 3;
  optional Vec4 fourth = 4;
}

message BinaryOp {
  enum Op {
    PLUS = 0;
    MINUS = 1;
    MUL = 2;
    DIV = 3;
    MOD = 4;
    XOR = 5;
    AND = 6;
    OR = 7;
    EQ = 8;
    NE = 9;
    LE = 10;
    GE = 11;
    LT = 12;
    GT = 13;
    SHL = 14;
    SHR = 15;
    LOGICAL_AND = 16;
    LOGICAL_OR = 17;
  };
  optional Op op = 1;
  optional Rvalue left = 2;
  optional Rvalue right = 3;
}

message UnaryOp {
  enum Op {
    PLUS = 0;
    MINUS = 1;
    TILDE = 2;
    NOT = 3;
  }
  optional Op op = 1;
  optional Rvalue rvalue = 2;
}

message Declare {
  optional Type type = 1;
  optional Var var = 2;
  optional Qualifier qualifier = 3;
  enum Qualifier {
    NO_QUALIFIER = 0;
    CONST_QUALIFIER = 1;
    IN_QUALIFIER = 2;
    OUT_QUALIFIER = 3;
    UNIFORM_QUALIFIER = 4;
    // TODO(nedwill): ES2 only
    // ATTRIBUTE_QUALIFIER = 5;
    // VARYING_QUALIFIER = 6;
    // TODO(nedwill): ES3.1 only
    // BUFFER_QUALIFIER = 7;
    // TODO(nedwill): compute shaders only
    // SHARED_QUALIFIER = 8;
  }
  optional Rvalue rvalue = 9;
}

// TODO: finish implementing operators
// https://www.khronos.org/registry/OpenGL/specs/gl/GLSLangSpec.4.60.html#operators
message Rvalue {
  oneof rvalue {
    Var var = 1;
    Const cons = 2;
    BinaryOp binary_op = 3;
    UnaryOp unary_op = 4;
  }
}

message Assignment {
  optional Lvalue lvalue = 1;
  optional Rvalue rvalue = 2;
}

message IfElse {
  optional Rvalue cond = 1;
  optional Block if_body = 2;
  optional Block else_body = 3;
}

message While {
  optional Rvalue cond = 1;
  optional Block body = 2;
}

message Statement {
  oneof statement {
    Assignment assignment = 1;
    IfElse ifelse = 2;
    While while_stmt = 3;
    Rvalue return_stmt = 4;
    Declare declare = 5;
  }
}

enum FunctionName {
  MAIN = 0;
  NAME_1 = 1;
  NAME_2 = 2;
  NAME_3 = 3;
}

message Block {
  repeated Statement statements = 1;
}

message Function {
  optional FunctionName function_name = 1;
  optional Block block = 2;
  optional Rvalue return_stmt = 3;
  optional Type type = 4;
  // TODO(nedwill): add arguments
}

message Shader {
  repeated Function functions = 1;
  // Global declarations
  repeated Declare declarations = 2;
}

message Session {
  optional Shader vertex_shader = 1;
  optional Shader fragment_shader = 2;
}