namespace STCompiler.Common;

using System.Collections.Generic;

public static class Bytecode {
    public const string Magic = "STBC";
    public const ushort Version = 2;
    public const ushort DefaultCycleTime = 100; // in milliseconds
    
    public static class OpCodes {
        public const byte NOP = 0x00;
        public const byte PUSH_CONST = 0x01;       // integer/long
        public const byte PUSH_REAL_CONST = 0x02;  // float/double
        public const byte LOAD_VAR = 0x03;
        public const byte STORE_VAR = 0x04;

        // Signed integer arithmetic (SINT, INT, DINT, LINT)
        public const byte ADD_SINT = 0x10; public const byte SUB_SINT = 0x11; public const byte MUL_SINT = 0x12; public const byte DIV_SINT = 0x13;
        public const byte ADD_INT  = 0x14; public const byte SUB_INT  = 0x15; public const byte MUL_INT  = 0x16; public const byte DIV_INT  = 0x17;
        public const byte ADD_DINT = 0x18; public const byte SUB_DINT = 0x19; public const byte MUL_DINT = 0x1A; public const byte DIV_DINT = 0x1B;
        public const byte ADD_LINT = 0x1C; public const byte SUB_LINT = 0x1D; public const byte MUL_LINT = 0x1E; public const byte DIV_LINT = 0x1F;

        // Unsigned integer arithmetic (USINT, UINT, UDINT, ULINT) - moved to avoid conflicts
        public const byte ADD_USINT = 0x22; public const byte SUB_USINT = 0x23; public const byte MUL_USINT = 0x24; public const byte DIV_USINT = 0x25;
        public const byte ADD_UINT  = 0x26; public const byte SUB_UINT  = 0x27; public const byte MUL_UINT  = 0x28; public const byte DIV_UINT  = 0x29;
        public const byte ADD_UDINT = 0x2A; public const byte SUB_UDINT = 0x2B; public const byte MUL_UDINT = 0x2C; public const byte DIV_UDINT = 0x2D;
        public const byte ADD_ULINT = 0x2E; public const byte SUB_ULINT = 0x2F; public const byte MUL_ULINT = 0x30; public const byte DIV_ULINT = 0x31;

        // Floating point arithmetic
        public const byte ADD_REAL = 0x40; public const byte SUB_REAL = 0x41; public const byte MUL_REAL = 0x42; public const byte DIV_REAL = 0x43;
        public const byte ADD_LREAL = 0x44; public const byte SUB_LREAL = 0x45; public const byte MUL_LREAL = 0x46; public const byte DIV_LREAL = 0x47;

        // Signed integer comparisons
        public const byte LT_SINT = 0x50; public const byte GT_SINT = 0x51; public const byte LE_SINT = 0x52; public const byte GE_SINT = 0x53; public const byte EQ_SINT = 0x54; public const byte NEQ_SINT = 0x55;
        public const byte LT_INT = 0x56; public const byte GT_INT = 0x57; public const byte LE_INT = 0x58; public const byte GE_INT = 0x59; public const byte EQ_INT = 0x5A; public const byte NEQ_INT = 0x5B;
        public const byte LT_DINT = 0x5C; public const byte GT_DINT = 0x5D; public const byte LE_DINT = 0x5E; public const byte GE_DINT = 0x5F; public const byte EQ_DINT = 0x60; public const byte NEQ_DINT = 0x61;
        public const byte LT_LINT = 0x62; public const byte GT_LINT = 0x63; public const byte LE_LINT = 0x64; public const byte GE_LINT = 0x65; public const byte EQ_LINT = 0x66; public const byte NEQ_LINT = 0x67;
        
        // Unsigned integer comparisons
        public const byte LT_USINT = 0x70; public const byte GT_USINT = 0x71; public const byte LE_USINT = 0x72; public const byte GE_USINT = 0x73; public const byte EQ_USINT = 0x74; public const byte NEQ_USINT = 0x75;
        public const byte LT_UINT = 0x76; public const byte GT_UINT = 0x77; public const byte LE_UINT = 0x78; public const byte GE_UINT = 0x79; public const byte EQ_UINT = 0x7A; public const byte NEQ_UINT = 0x7B;
        public const byte LT_UDINT = 0x7C; public const byte GT_UDINT = 0x7D; public const byte LE_UDINT = 0x7E; public const byte GE_UDINT = 0x7F; public const byte EQ_UDINT = 0x80; public const byte NEQ_UDINT = 0x81;
        public const byte LT_ULINT = 0x82; public const byte GT_ULINT = 0x83; public const byte LE_ULINT = 0x84; public const byte GE_ULINT = 0x85; public const byte EQ_ULINT = 0x86; public const byte NEQ_ULINT = 0x87;
        
        // Floating point comparisons
        public const byte LT_REAL = 0x90; public const byte GT_REAL = 0x91; public const byte LE_REAL = 0x92; public const byte GE_REAL = 0x93; public const byte EQ_REAL = 0x94; public const byte NEQ_REAL = 0x95;
        public const byte LT_LREAL = 0x96; public const byte GT_LREAL = 0x97; public const byte LE_LREAL = 0x98; public const byte GE_LREAL = 0x99; public const byte EQ_LREAL = 0x9A; public const byte NEQ_LREAL = 0x9B;

        // Control flow
        public const byte JZ = 0xA0;
        public const byte JMP = 0xA1;

        // Array operations
        public const byte ARRAY_BOUNDS_CHECK = 0xE0;

        public const byte HALT = 0xF0;
    }

    static readonly Dictionary<byte, string> names = new() {
        { OpCodes.NOP, "NOP" },
        { OpCodes.PUSH_CONST, "PUSH_CONST" },
        { OpCodes.PUSH_REAL_CONST, "PUSH_REAL_CONST" },
        { OpCodes.LOAD_VAR, "LOAD_VAR" },
        { OpCodes.STORE_VAR, "STORE_VAR" },
        { OpCodes.ADD_SINT, "ADD_SINT" }, { OpCodes.SUB_SINT, "SUB_SINT" }, { OpCodes.MUL_SINT, "MUL_SINT" }, { OpCodes.DIV_SINT, "DIV_SINT" },
        { OpCodes.ADD_INT, "ADD_INT" }, { OpCodes.SUB_INT, "SUB_INT" }, { OpCodes.MUL_INT, "MUL_INT" }, { OpCodes.DIV_INT, "DIV_INT" },
        { OpCodes.ADD_DINT, "ADD_DINT" }, { OpCodes.SUB_DINT, "SUB_DINT" }, { OpCodes.MUL_DINT, "MUL_DINT" }, { OpCodes.DIV_DINT, "DIV_DINT" },
        { OpCodes.ADD_LINT, "ADD_LINT" }, { OpCodes.SUB_LINT, "SUB_LINT" }, { OpCodes.MUL_LINT, "MUL_LINT" }, { OpCodes.DIV_LINT, "DIV_LINT" },
        { OpCodes.ADD_USINT, "ADD_USINT" }, { OpCodes.SUB_USINT, "SUB_USINT" }, { OpCodes.MUL_USINT, "MUL_USINT" }, { OpCodes.DIV_USINT, "DIV_USINT" },
        { OpCodes.ADD_UINT, "ADD_UINT" }, { OpCodes.SUB_UINT, "SUB_UINT" }, { OpCodes.MUL_UINT, "MUL_UINT" }, { OpCodes.DIV_UINT, "DIV_UINT" },
        { OpCodes.ADD_UDINT, "ADD_UDINT" }, { OpCodes.SUB_UDINT, "SUB_UDINT" }, { OpCodes.MUL_UDINT, "MUL_UDINT" }, { OpCodes.DIV_UDINT, "DIV_UDINT" },
        { OpCodes.ADD_ULINT, "ADD_ULINT" }, { OpCodes.SUB_ULINT, "SUB_ULINT" }, { OpCodes.MUL_ULINT, "MUL_ULINT" }, { OpCodes.DIV_ULINT, "DIV_ULINT" },
        { OpCodes.ADD_REAL, "ADD_REAL" }, { OpCodes.SUB_REAL, "SUB_REAL" }, { OpCodes.MUL_REAL, "MUL_REAL" }, { OpCodes.DIV_REAL, "DIV_REAL" },
        { OpCodes.ADD_LREAL, "ADD_LREAL" }, { OpCodes.SUB_LREAL, "SUB_LREAL" }, { OpCodes.MUL_LREAL, "MUL_LREAL" }, { OpCodes.DIV_LREAL, "DIV_LREAL" },
        { OpCodes.LT_SINT, "LT_SINT" }, { OpCodes.GT_SINT, "GT_SINT" }, { OpCodes.LE_SINT, "LE_SINT" }, { OpCodes.GE_SINT, "GE_SINT" }, { OpCodes.EQ_SINT, "EQ_SINT" }, { OpCodes.NEQ_SINT, "NEQ_SINT" },
        { OpCodes.LT_INT, "LT_INT" }, { OpCodes.GT_INT, "GT_INT" }, { OpCodes.LE_INT, "LE_INT" }, { OpCodes.GE_INT, "GE_INT" }, { OpCodes.EQ_INT, "EQ_INT" }, { OpCodes.NEQ_INT, "NEQ_INT" },
        { OpCodes.LT_DINT, "LT_DINT" }, { OpCodes.GT_DINT, "GT_DINT" }, { OpCodes.LE_DINT, "LE_DINT" }, { OpCodes.GE_DINT, "GE_DINT" }, { OpCodes.EQ_DINT, "EQ_DINT" }, { OpCodes.NEQ_DINT, "NEQ_DINT" },
        { OpCodes.LT_LINT, "LT_LINT" }, { OpCodes.GT_LINT, "GT_LINT" }, { OpCodes.LE_LINT, "LE_LINT" }, { OpCodes.GE_LINT, "GE_LINT" }, { OpCodes.EQ_LINT, "EQ_LINT" }, { OpCodes.NEQ_LINT, "NEQ_LINT" },
        { OpCodes.LT_USINT, "LT_USINT" }, { OpCodes.GT_USINT, "GT_USINT" }, { OpCodes.LE_USINT, "LE_USINT" }, { OpCodes.GE_USINT, "GE_USINT" }, { OpCodes.EQ_USINT, "EQ_USINT" }, { OpCodes.NEQ_USINT, "NEQ_USINT" },
        { OpCodes.LT_UINT, "LT_UINT" }, { OpCodes.GT_UINT, "GT_UINT" }, { OpCodes.LE_UINT, "LE_UINT" }, { OpCodes.GE_UINT, "GE_UINT" }, { OpCodes.EQ_UINT, "EQ_UINT" }, { OpCodes.NEQ_UINT, "NEQ_UINT" },
        { OpCodes.LT_UDINT, "LT_UDINT" }, { OpCodes.GT_UDINT, "GT_UDINT" }, { OpCodes.LE_UDINT, "LE_UDINT" }, { OpCodes.GE_UDINT, "GE_UDINT" }, { OpCodes.EQ_UDINT, "EQ_UDINT" }, { OpCodes.NEQ_UDINT, "NEQ_UDINT" },
        { OpCodes.LT_ULINT, "LT_ULINT" }, { OpCodes.GT_ULINT, "GT_ULINT" }, { OpCodes.LE_ULINT, "LE_ULINT" }, { OpCodes.GE_ULINT, "GE_ULINT" }, { OpCodes.EQ_ULINT, "EQ_ULINT" }, { OpCodes.NEQ_ULINT, "NEQ_ULINT" },
        { OpCodes.LT_REAL, "LT_REAL" }, { OpCodes.GT_REAL, "GT_REAL" }, { OpCodes.LE_REAL, "LE_REAL" }, { OpCodes.GE_REAL, "GE_REAL" }, { OpCodes.EQ_REAL, "EQ_REAL" }, { OpCodes.NEQ_REAL, "NEQ_REAL" },
        { OpCodes.LT_LREAL, "LT_LREAL" }, { OpCodes.GT_LREAL, "GT_LREAL" }, { OpCodes.LE_LREAL, "LE_LREAL" }, { OpCodes.GE_LREAL, "GE_LREAL" }, { OpCodes.EQ_LREAL, "EQ_LREAL" }, { OpCodes.NEQ_LREAL, "NEQ_LREAL" },
        { OpCodes.JZ, "JZ" }, { OpCodes.JMP, "JMP" },
        { OpCodes.ARRAY_BOUNDS_CHECK, "ARRAY_BOUNDS_CHECK" },
        { OpCodes.HALT, "HALT" }
    };

    public static string OpName(byte op) => names.TryGetValue(op, out var s) ? s : ($"0x{op:X2}");
}