package commands

import (
	"fmt"
	"strings"

	"c65gm/internal/compiler"
	"c65gm/internal/preproc"
	"c65gm/internal/utils"
)

// EndIfCommand handles ENDIF statements to close IF...ENDIF blocks
// Syntax: ENDIF
type EndIfCommand struct {
	endLabel string
}

func (c *EndIfCommand) WillHandle(line preproc.Line) bool {
	params, err := utils.ParseParams(line.Text)
	if err != nil || len(params) == 0 {
		return false
	}

	return strings.ToUpper(params[0]) == "ENDIF"
}

func (c *EndIfCommand) Interpret(line preproc.Line, ctx *compiler.CompilerContext) error {
	params, err := utils.ParseParams(line.Text)
	if err != nil {
		return err
	}

	if len(params) != 1 {
		return fmt.Errorf("ENDIF: wrong number of parameters (%d), expected 1", len(params))
	}

	// Pop the end label (from IF or ELSE)
	label, err := ctx.IfStack.Pop()
	if err != nil {
		return fmt.Errorf("ENDIF: %w", err)
	}
	c.endLabel = label

	return nil
}

func (c *EndIfCommand) Generate(_ *compiler.CompilerContext) ([]string, error) {
	// Just place the end label
	return []string{c.endLabel}, nil
}