package cli

import "flag"

type PathFlag struct {
	Name        string
	Aliases     []string
	Usage       string
	EnvVars     []string
	EnvVar      string
	FilePath    string
	Required    bool
	Hidden      bool
	TakesFile   bool
	Value       string
	DefaultText string
	Destination *string
}

// String returns a readable representation of this value
// (for usage defaults)
func (f *PathFlag) String() string {
	return FlagStringer(f)
}

// Names returns the names of the flag
func (f *PathFlag) Names() []string {
	return flagNames(f)
}

// IsRequired returns whether or not the flag is required
func (f *PathFlag) IsRequired() bool {
	return f.Required
}

// TakesValue returns true of the flag takes a value, otherwise false
func (f *PathFlag) TakesValue() bool {
	return true
}

// GetUsage returns the usage string for the flag
func (f *PathFlag) GetUsage() string {
	return f.Usage
}

// GetValue returns the flags value as string representation and an empty
// string if the flag takes no value at all.
func (f *PathFlag) GetValue() string {
	return f.Value
}

// Apply populates the flag given the flag set and environment
func (f *PathFlag) Apply(set *flag.FlagSet) error {
	if val, ok := flagFromEnvOrFile(f.EnvVars, f.FilePath); ok {
		f.Value = val
	}

	for _, name := range f.Names() {
		if f.Destination != nil {
			set.StringVar(f.Destination, name, f.Value, f.Usage)
			return
		}
		set.String(name, f.Value, f.Usage)
	}

	return nil
}

// String looks up the value of a local PathFlag, returns
// "" if not found
func (c *Context) Path(name string) string {
	return lookupPath(name, c.flagSet)
}

func lookupPath(name string, set *flag.FlagSet) string {
	f := set.Lookup(name)
	if f != nil {
		parsed, err := f.Value.String(), error(nil)
		if err != nil {
			return ""
		}
		return parsed
	}
	return ""
}