package geo

import "strings"

// States is the US states + DC allowlist (code -> name).
var States = []struct {
	Code string
	Name string
}{
	{"AL", "Alabama"}, {"AK", "Alaska"}, {"AZ", "Arizona"}, {"AR", "Arkansas"}, {"CA", "California"},
	{"CO", "Colorado"}, {"CT", "Connecticut"}, {"DE", "Delaware"}, {"DC", "District of Columbia"},
	{"FL", "Florida"}, {"GA", "Georgia"}, {"HI", "Hawaii"}, {"ID", "Idaho"}, {"IL", "Illinois"},
	{"IN", "Indiana"}, {"IA", "Iowa"}, {"KS", "Kansas"}, {"KY", "Kentucky"}, {"LA", "Louisiana"},
	{"ME", "Maine"}, {"MD", "Maryland"}, {"MA", "Massachusetts"}, {"MI", "Michigan"}, {"MN", "Minnesota"},
	{"MS", "Mississippi"}, {"MO", "Missouri"}, {"MT", "Montana"}, {"NE", "Nebraska"}, {"NV", "Nevada"},
	{"NH", "New Hampshire"}, {"NJ", "New Jersey"}, {"NM", "New Mexico"}, {"NY", "New York"},
	{"NC", "North Carolina"}, {"ND", "North Dakota"}, {"OH", "Ohio"}, {"OK", "Oklahoma"}, {"OR", "Oregon"},
	{"PA", "Pennsylvania"}, {"RI", "Rhode Island"}, {"SC", "South Carolina"}, {"SD", "South Dakota"},
	{"TN", "Tennessee"}, {"TX", "Texas"}, {"UT", "Utah"}, {"VT", "Vermont"}, {"VA", "Virginia"},
	{"WA", "Washington"}, {"WV", "West Virginia"}, {"WI", "Wisconsin"}, {"WY", "Wyoming"},
}

var codes map[string]struct{}

func init() {
	codes = make(map[string]struct{}, len(States))
	for _, s := range States {
		codes[s.Code] = struct{}{}
	}
}

// ValidState reports whether state is empty or a known US code.
func ValidState(state string) bool {
	state = strings.ToUpper(strings.TrimSpace(state))
	if state == "" {
		return true
	}
	_, ok := codes[state]
	return ok
}

// NormalizeState returns "" or an uppercase 2-letter code.
func NormalizeState(state string) string {
	return strings.ToUpper(strings.TrimSpace(state))
}

// StateName returns the full name for a US state code, or "" if unknown.
func StateName(code string) string {
	code = NormalizeState(code)
	for _, s := range States {
		if s.Code == code {
			return s.Name
		}
	}
	return ""
}