#ifndef AMALGAM_BYTECODE_H
#define AMALGAM_BYTECODE_H

#include "../std/defs.h"
#include "../std/misc.h"
#include "../std/buffer.h"
#include "../defs.h"

#include <setjmp.h>

/*doc(Opcode)
    # Opcode
    Variable length opcodes. Sizes range from 1 to 4 bytes.
    # Instruction formats
    Instructions can be in 6 different formats:
    1. 1 byte: Opcode
    2. 2 bytes: Opcode + register
    3. 3 bytes: Opcode + register + register
    4. 3 bytes:\
    4.1 Opcode + intermediate\
    4.2 Opcode + data\
    4.3 Opcode + index\
    4.4 Opcode + offset
    5. 4 bytes: Opcode + register + register + register
    6. 4 bytes: Opcode + register + offset
*/
typedef enum {
    AMAL_OP_NOP,         /* No operation. This can be used for patching */
    AMAL_OP_SETZ,        /* setz reg             - Set register value to 0 */
    AMAL_OP_MOV,         /* mov dst, src         - move src register to dst register */
    AMAL_OP_MOVI,        /* movi dst, src        - move src intermediate to dst register */
    AMAL_OP_MOVD,        /* movd dst, src        - move src data to dst register */
    AMAL_OP_ADD,         /* add dst, reg1, reg2 */
    AMAL_OP_SUB,         /* sub dst, reg1, reg2 */
    AMAL_OP_MUL,         /* mul dst, reg1, reg2 */
    AMAL_OP_DIV,         /* div dst, reg1, reg2 */
    AMAL_OP_PUSH,        /* push reg             - Push register onto stack */
    AMAL_OP_PUSHI,       /* pushi int            - Push intermediate onto stack */
    AMAL_OP_PUSHD,       /* pushd data           - Push data onto stack */
    AMAL_OP_CALL,        /* call fi              - Call a function using function index (fi). fi is u16 */
    AMAL_OP_CALLR,       /* callr reg            - Call a function using a register. Used for function pointers */
    AMAL_OP_CMP,         /* cmp dst, reg1, reg2  - Set dst to 1 if reg1 equals reg2, otherwise set it to 0 */
    AMAL_OP_JZ,          /* jz reg, offset       - jump to offset if reg is zero. offset is i16 */
    AMAL_OP_JMP,         /* jmp offset           - unconditional jump to offset. offset is i16 */
    AMAL_OP_RET,         /* ret */
    AMAL_OP_FUNC_START,  /* func_start */
    AMAL_OP_FUNC_END     /* func_end */
} AmalOpcode;

typedef u8 AmalOpcodeType;

typedef struct {
    Buffer/*<instruction data>*/ instructions;
} Bytecode;

typedef struct {
    jmp_buf env;
    Bytecode *bytecode;
    Parser *parser; /* borrowed */
} BytecodeCompilerContext;

CHECK_RESULT int bytecode_init(Bytecode *self, ScopedAllocator *allocator);

/* longjump to self->env on failure */
void generate_bytecode_from_ssa(BytecodeCompilerContext *self);

#endif