package compileopts

import (
	"fmt"
	"strings"
)

var (
	validGCOptions            = []string{"none", "leaking", "extalloc", "conservative"}
	validSchedulerOptions     = []string{"none", "tasks", "coroutines"}
	validPrintSizeOptions     = []string{"none", "short", "full"}
	validPanicStrategyOptions = []string{"print", "trap"}
	validOptOptions           = []string{"none", "0", "1", "2", "s", "z"}
)

// Options contains extra options to give to the compiler. These options are
// usually passed from the command line.
type Options struct {
	Target        string
	Opt           string
	GC            string
	PanicStrategy string
	Scheduler     string
	PrintIR       bool
	DumpSSA       bool
	VerifyIR      bool
	PrintCommands bool
	Debug         bool
	PrintSizes    string
	PrintStacks   bool
	Tags          string
	WasmAbi       string
	TestConfig    TestConfig
	Programmer    string
}

// Verify performs a validation on the given options, raising an error if options are not valid.
func (o *Options) Verify() error {
	if o.GC != "" {
		valid := isInArray(validGCOptions, o.GC)
		if !valid {
			return fmt.Errorf(`invalid gc option '%s': valid values are %s`,
				o.GC,
				strings.Join(validGCOptions, ", "))
		}
	}

	if o.Scheduler != "" {
		valid := isInArray(validSchedulerOptions, o.Scheduler)
		if !valid {
			return fmt.Errorf(`invalid scheduler option '%s': valid values are %s`,
				o.Scheduler,
				strings.Join(validSchedulerOptions, ", "))
		}
	}

	if o.PrintSizes != "" {
		valid := isInArray(validPrintSizeOptions, o.PrintSizes)
		if !valid {
			return fmt.Errorf(`invalid size option '%s': valid values are %s`,
				o.PrintSizes,
				strings.Join(validPrintSizeOptions, ", "))
		}
	}

	if o.PanicStrategy != "" {
		valid := isInArray(validPanicStrategyOptions, o.PanicStrategy)
		if !valid {
			return fmt.Errorf(`invalid panic option '%s': valid values are %s`,
				o.PanicStrategy,
				strings.Join(validPanicStrategyOptions, ", "))
		}
	}

	if o.Opt != "" {
		if !isInArray(validOptOptions, o.Opt) {
			return fmt.Errorf("invalid -opt=%s: valid values are %s", o.Opt, strings.Join(validOptOptions, ", "))
		}
	}

	return nil
}

func isInArray(arr []string, item string) bool {
	for _, i := range arr {
		if i == item {
			return true
		}
	}
	return false
}