package i18n

import (
	"testing"
	"time"

	"github.com/lukaszkasprzak/prognosis/internal/config"
)

func TestForFallsBackToEnglish(t *testing.T) {
	if For("klingon").Lang() != EN {
		t.Fatal("an unknown language must degrade to English, not to empty strings")
	}
	if For("pl").Lang() != PL {
		t.Fatal("pl must resolve to the Polish catalogue")
	}
}

// Every catalogue must cover every column, or a table in that language would
// silently fall back to the internal column name.
func TestEveryLanguageCoversEveryColumn(t *testing.T) {
	for _, lang := range []Lang{EN, PL} {
		c := For(string(lang))
		for _, col := range config.ValidColumns() {
			if _, ok := c.headers[col]; !ok {
				t.Errorf("%s: no header for column %q", lang, col)
			}
		}
	}
}

// The WMO codes must match across languages: a code described in English but
// not Polish would print "code 71" to a Polish reader.
func TestConditionCoverageMatchesAcrossLanguages(t *testing.T) {
	en, pl := For("en"), For("pl")
	for code := range en.conditions {
		if _, ok := pl.conditions[code]; !ok {
			t.Errorf("code %d described in English but not Polish", code)
		}
	}
	for code := range pl.conditions {
		if _, ok := en.conditions[code]; !ok {
			t.Errorf("code %d described in Polish but not English", code)
		}
	}
}

func TestWordAndSpeciesCoverageMatches(t *testing.T) {
	en, pl := For("en"), For("pl")
	for k := range en.words {
		if _, ok := pl.words[k]; !ok {
			t.Errorf("word %q missing from Polish", k)
		}
	}
	for _, s := range config.AllSpecies {
		if _, ok := en.species[s]; !ok {
			t.Errorf("species %q missing from English", s)
		}
		if _, ok := pl.species[s]; !ok {
			t.Errorf("species %q missing from Polish", s)
		}
	}
	for _, b := range []string{"none", "low", "medium", "high", "very high"} {
		if en.Band(b) == b && b != "none" && b != "low" && b != "medium" && b != "high" && b != "very high" {
			t.Errorf("band %q missing from English", b)
		}
		if pl.Band(b) == b {
			t.Errorf("band %q not translated to Polish", b)
		}
	}
}

func TestUnknownCodeIsVisible(t *testing.T) {
	got := For("en").Condition(4242)
	if got != "code 4242" {
		t.Fatalf("unknown codes must be visible, got %q", got)
	}
}

func TestDate(t *testing.T) {
	d := time.Date(2026, 8, 10, 13, 0, 0, 0, time.UTC) // a Monday
	if got, want := For("en").Date(d), "Mon 10 Aug"; got != want {
		t.Errorf("en date = %q, want %q", got, want)
	}
	if got, want := For("pl").Date(d), "pn 10 sie"; got != want {
		t.Errorf("pl date = %q, want %q", got, want)
	}
}