// bytecode.go
package types

// SourcePos represents a position in the source code
type SourcePos struct {
	Line   int
	Column int
}

// OpCode represents a bytecode instruction
type OpCode byte

const (
	OP_CONSTANT OpCode = iota
	OP_NIL
	OP_TRUE
	OP_FALSE
	OP_POP
	OP_GET_LOCAL
	OP_SET_LOCAL
	OP_GET_GLOBAL
	OP_SET_GLOBAL
	OP_EQUAL
	OP_GREATER
	OP_LESS
	OP_ADD
	OP_SUBTRACT
	OP_MULTIPLY
	OP_DIVIDE
	OP_NOT
	OP_NEGATE
	OP_PRINT
	OP_JUMP
	OP_JUMP_IF_FALSE
	OP_CALL
	OP_RETURN
)

// String returns the string representation of an OpCode
func (op OpCode) String() string {
	names := [...]string{
		"OP_CONSTANT", "OP_NIL", "OP_TRUE", "OP_FALSE",
		"OP_POP", "OP_GET_LOCAL", "OP_SET_LOCAL", "OP_GET_GLOBAL",
		"OP_SET_GLOBAL", "OP_EQUAL", "OP_GREATER", "OP_LESS",
		"OP_ADD", "OP_SUBTRACT", "OP_MULTIPLY", "OP_DIVIDE",
		"OP_NOT", "OP_NEGATE", "OP_PRINT", "OP_JUMP",
		"OP_JUMP_IF_FALSE", "OP_CALL", "OP_RETURN",
	}
	return names[op]
}

// Instruction represents a single bytecode instruction
type Instruction struct {
	Op       OpCode
	Operands []byte
	Pos      SourcePos // Source position for debugging
}

// Chunk represents a chunk of bytecode
type Chunk struct {
	Code      []Instruction
	Constants []Value
}

// Function represents a function in bytecode
type Function struct {
	Name         string
	Arity        int
	Chunk        *Chunk
	LocalCount   int
	UpvalueCount int
}

// Environment represents a variable scope
type Environment struct {
	Values    map[string]Value
	Enclosing *Environment
}

// NewEnvironment creates a new environment
func NewEnvironment(enclosing *Environment) *Environment {
	return &Environment{
		Values:    make(map[string]Value),
		Enclosing: enclosing,
	}
}