//
// Created by 李晓明 on 2023/8/16.
//

#include "debug.h"
#include "value.h"
#include <stdio.h>
static int constantInstruction(const char *, Chunk *, int);
static int simpleInstruction(const char *name, int offset);
static int byteInstruction(const char *name, Chunk *chunk, int offset);

void disassembleChunk(Chunk *chunk, const char *name) {
  printf("== %s STARTING ==\n", name);

  for (int offset = 0; offset < chunk->count;) {
    offset = disassembleInstruction(chunk, offset);
  }
  printf("== %s END ==\n", name);
}
static int jumpInstruction(const char *name, int sign, Chunk *chunk, int offset) {
  uint16_t jump = (uint16_t) (chunk->code[offset + 1] << 8);
  jump |= chunk->code[offset + 2];
  printf("%-16s %4d -> %d\n", name, offset, offset + 3 + sign * jump);
  return offset + 3;
}
int disassembleInstruction(Chunk *chunk, int offset) {
  printf("%04d ", offset);

  if (offset > 0 && chunk->lines[offset] == chunk->lines[offset - 1]) {
    printf("   | ");
  } else {
    printf("%4d ", chunk->lines[offset]);
  }

  uint8_t instruction = chunk->code[offset];
  switch (instruction) {
    case OP_CONSTANT: return constantInstruction("OP_CONSTANT", chunk, offset);
    case OP_NIL: return simpleInstruction("OP_NIL", offset);
    case OP_TRUE: return simpleInstruction("OP_TRUE", offset);
    case OP_FALSE: return simpleInstruction("OP_FALSE", offset);
    case OP_POP: return simpleInstruction("OP_POP", offset);
    case OP_DEFINE_GLOBAL: return constantInstruction("OP_DEFINE_GLOBAL", chunk, offset);
    case OP_GET_GLOBAL: return constantInstruction("OP_GET_GLOBAL", chunk, offset);
    case OP_SET_GLOBAL: return constantInstruction("OP_SET_GLOBAL", chunk, offset);
    case OP_GET_LOCAL: return byteInstruction("OP_GET_LOCAL", chunk, offset);
    case OP_SET_LOCAL: return byteInstruction("OP_SET_LOCAL", chunk, offset);
    case OP_ADD: return simpleInstruction("OP_ADD", offset);
    case OP_SUBTRACT: return simpleInstruction("OP_SUBTRACT", offset);
    case OP_MULTIPLY: return simpleInstruction("OP_MULTIPLY", offset);
    case OP_DIVIDE: return simpleInstruction("OP_DIVIDE", offset);
    case OP_NOT: return simpleInstruction("OP_NOT", offset);
    case OP_NEGATE: return simpleInstruction("OP_NEGATE", offset);
    case OP_EQUAL: return simpleInstruction("OP_EQUAL", offset);
    case OP_GREATER: return simpleInstruction("OP_GREATER", offset);
    case OP_LESS: return simpleInstruction("OP_LESS", offset);
    case OP_PRINT: return simpleInstruction("OP_PRINT", offset);
    case OP_JUMP: return jumpInstruction("OP_JUMP", 1, chunk, offset);
    case OP_LOOP: return jumpInstruction("OP_LOOP", -1, chunk, offset);
    case OP_CALL: return byteInstruction("OP_CALL", chunk, offset);
    case OP_JUMP_IF_FALSE: return jumpInstruction("OP_JUMP_IF_FALSE", 1, chunk, offset);
    case OP_RETURN: return simpleInstruction("OP_RETURN", offset);
    default:
      printf("Unknown opcode %d\n", instruction);
      return offset + 1;
  }
}
/**
 * @brief 打印常量指令
 * @param name
 * @param chunk
 * @param offset
 * @return
 */
static int constantInstruction(const char *name, Chunk *chunk, int offset) {
  uint8_t constant = chunk->code[offset + 1];
  printf("%-16s %4d '", name, constant);
  printValue(chunk->constants.values[constant]);
  printf("'\n");
  return offset + 2;
}
/**
* @brief 打印指令
* @param name 名称
* @param offset 偏移
* @return
*/
static int simpleInstruction(const char *name, int offset) {
  printf("%s\n", name);
  return offset + 1;
}
static int byteInstruction(const char *name, Chunk *chunk, int offset) {
  uint8_t slot = chunk->code[offset + 1];
  printf("%-16s %4d\n", name, slot);
  return offset + 2;
}