package services

import (
	"strings"

	goi18n "github.com/nicksnyder/go-i18n/v2/i18n"

	"github.com/treytartt/honeydue-api/internal/dto/responses"
	"github.com/treytartt/honeydue-api/internal/i18n"
)

// lookup kinds — the message-key namespace for each localizable lookup type.
const (
	lookupKindResidenceType = "residence_type"
	lookupKindTaskCategory  = "task_category"
	lookupKindTaskPriority  = "task_priority"
	lookupKindTaskFrequency = "task_frequency"
	lookupKindSpecialty     = "contractor_specialty"
	lookupKindHomeProfile   = "home_profile"
	lookupKindDocumentType  = "document_type"
	lookupKindDocumentCat   = "document_category"
)

// documentTypeValues / documentCategoryValues are the stable client enum codes
// (see iOS DocumentType/DocumentCategory). Display labels are localized at
// request time. Order is presentation order.
var documentTypeValues = []string{
	"warranty", "manual", "receipt", "inspection", "permit", "deed", "insurance", "contract", "photo", "other",
}

var documentCategoryValues = []string{
	"appliance", "hvac", "plumbing", "electrical", "roofing", "structural", "landscaping", "general", "other",
}

// localizedList maps a list of stable values to {value, localized display}.
func localizedList(localizer *goi18n.Localizer, kind string, values []string) []HomeProfileOption {
	out := make([]HomeProfileOption, 0, len(values))
	for _, v := range values {
		out = append(out, HomeProfileOption{
			Value:       v,
			DisplayName: localizeLookup(localizer, kind, v),
		})
	}
	return out
}

// BuildDocumentTypes returns localized document-type options.
func BuildDocumentTypes(localizer *goi18n.Localizer) []HomeProfileOption {
	return localizedList(localizer, lookupKindDocumentType, documentTypeValues)
}

// BuildDocumentCategories returns localized document-category options.
func BuildDocumentCategories(localizer *goi18n.Localizer) []HomeProfileOption {
	return localizedList(localizer, lookupKindDocumentCat, documentCategoryValues)
}

// lookupSlug normalizes a stable English lookup name (or option value) into a
// message-key slug: lowercased, non-alphanumeric runs collapsed to "_".
// "Pest Control" -> "pest_control", "Bi-Weekly" -> "bi_weekly", "tank_gas" ->
// "tank_gas".
func lookupSlug(name string) string {
	var b strings.Builder
	prevUnderscore := false
	for _, r := range strings.ToLower(strings.TrimSpace(name)) {
		switch {
		case (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9'):
			b.WriteRune(r)
			prevUnderscore = false
		default:
			if !prevUnderscore && b.Len() > 0 {
				b.WriteByte('_')
				prevUnderscore = true
			}
		}
	}
	return strings.Trim(b.String(), "_")
}

// localizeLookup returns the localized display label for a lookup value.
// Keys follow "lookup.<kind>.<slug>". If the locale lacks the key it falls back
// to English, and ultimately to the original name so a raw key never surfaces.
func localizeLookup(localizer *goi18n.Localizer, kind, name string) string {
	key := "lookup." + kind + "." + lookupSlug(name)
	msg := i18n.T(localizer, key, nil)
	if msg == key {
		msg = i18n.T(i18n.NewLocalizer(i18n.DefaultLanguage), key, nil)
	}
	if msg == key {
		// No translation anywhere — fall back to the stable English name.
		return name
	}
	return msg
}

// HomeProfileOption is a single selectable value for a home-profile field.
type HomeProfileOption struct {
	Value       string `json:"value"`
	DisplayName string `json:"display_name"`
}

// homeProfileCatalog is the canonical set of home-profile field options,
// mirroring the (previously hardcoded) iOS dropdowns. Order is presentation
// order. Display labels are localized at request time via localizeLookup.
var homeProfileCatalog = []struct {
	Field  string
	Values []string
}{
	{"heating_type", []string{"gas_furnace", "electric_furnace", "heat_pump", "boiler", "radiant", "other"}},
	{"cooling_type", []string{"central_ac", "window_ac", "heat_pump", "evaporative", "none", "other"}},
	{"water_heater_type", []string{"tank_gas", "tank_electric", "tankless_gas", "tankless_electric", "heat_pump", "solar", "other"}},
	{"roof_type", []string{"asphalt_shingle", "metal", "tile", "slate", "wood_shake", "flat", "other"}},
	{"exterior_type", []string{"brick", "vinyl_siding", "wood_siding", "stucco", "stone", "fiber_cement", "other"}},
	{"flooring_primary", []string{"hardwood", "laminate", "tile", "carpet", "vinyl", "concrete", "other"}},
	{"landscaping_type", []string{"lawn", "desert", "xeriscape", "garden", "mixed", "none", "other"}},
}

// BuildHomeProfileOptions returns the home-profile field options with display
// labels localized for the supplied localizer (nil falls back to English).
func BuildHomeProfileOptions(localizer *goi18n.Localizer) map[string][]HomeProfileOption {
	out := make(map[string][]HomeProfileOption, len(homeProfileCatalog))
	for _, f := range homeProfileCatalog {
		opts := make([]HomeProfileOption, 0, len(f.Values))
		for _, v := range f.Values {
			opts = append(opts, HomeProfileOption{
				Value:       v,
				DisplayName: localizeLookup(localizer, lookupKindHomeProfile, v),
			})
		}
		out[f.Field] = opts
	}
	return out
}

// LocalizeLookups fills the DisplayName of each lookup slice in place, using the
// supplied localizer. Mutates the passed slices.
func LocalizeLookups(
	localizer *goi18n.Localizer,
	residenceTypes []responses.ResidenceTypeResponse,
	categories []responses.TaskCategoryResponse,
	priorities []responses.TaskPriorityResponse,
	frequencies []responses.TaskFrequencyResponse,
	specialties []responses.ContractorSpecialtyResponse,
) {
	for i := range residenceTypes {
		residenceTypes[i].DisplayName = localizeLookup(localizer, lookupKindResidenceType, residenceTypes[i].Name)
	}
	for i := range categories {
		categories[i].DisplayName = localizeLookup(localizer, lookupKindTaskCategory, categories[i].Name)
	}
	for i := range priorities {
		priorities[i].DisplayName = localizeLookup(localizer, lookupKindTaskPriority, priorities[i].Name)
	}
	for i := range frequencies {
		frequencies[i].DisplayName = localizeLookup(localizer, lookupKindTaskFrequency, frequencies[i].Name)
	}
	for i := range specialties {
		specialties[i].DisplayName = localizeLookup(localizer, lookupKindSpecialty, specialties[i].Name)
	}
}