package tui

import (
	"errors"
	"strings"
	"testing"

	tea "github.com/charmbracelet/bubbletea"

	"github.com/lukaszkasprzak/lectio/internal/config"
	"github.com/lukaszkasprzak/lectio/internal/liturgy"
)

func TestVersionCycle(t *testing.T) {
	m := New(config.Config{Versions: []string{"bt", "wuj", "vul"}, DefaultVersion: "bt"}, "", "")
	if m.version() != "bt" {
		t.Fatalf("start = %q", m.version())
	}
	m = m.cycleVersion(+1)
	if m.version() != "wuj" {
		t.Errorf("after tab = %q", m.version())
	}
	m = m.cycleVersion(-1)
	if m.version() != "bt" {
		t.Errorf("after shift-tab = %q", m.version())
	}
}

func TestOfflineDropsBT(t *testing.T) {
	m := New(config.Config{Versions: []string{"bt", "wuj", "vul"}, DefaultVersion: "bt", Offline: true}, "", "")
	for _, v := range m.versions {
		if v == "bt" {
			t.Error("offline model kept bt")
		}
	}
}

// TestBodyLinesLocalisesMessages checks that the loading/no-readings/error
// messages follow cfg.UILanguage.
func TestBodyLinesLocalisesMessages(t *testing.T) {
	en := Model{cfg: config.Config{UILanguage: "en"}, loading: true}
	if lines := en.bodyLines(80); len(lines) == 0 || !strings.Contains(lines[0], "loading") {
		t.Errorf("en loading bodyLines = %v, want it to contain %q", lines, "loading")
	}

	pl := Model{cfg: config.Config{UILanguage: "pl"}, loading: true}
	if lines := pl.bodyLines(80); len(lines) == 0 || !strings.Contains(lines[0], "ładowanie") {
		t.Errorf("pl loading bodyLines = %v, want it to contain %q", lines, "ładowanie")
	}

	enEmpty := Model{cfg: config.Config{UILanguage: "en"}, date: "2026-07-22"}
	if lines := enEmpty.bodyLines(80); len(lines) == 0 || !strings.Contains(lines[0], "no readings for") {
		t.Errorf("en no-readings bodyLines = %v, want it to contain %q", lines, "no readings for")
	}
}

// TestBodyLinesSingleSpaceConcatenation is a regression test for the
// i18n-migration whitespace bug: i18n.UI.NoReadingsFor/ErrorPrefix must
// carry exactly one trailing space, since bodyLines concatenates the date/
// error string directly onto them with no separator of its own -- the
// pre-i18n TUI code produced "błąd: " + err / "brak czytań na " + date (one
// space), and the i18n fields regressed to two.
func TestBodyLinesSingleSpaceConcatenation(t *testing.T) {
	enEmpty := Model{cfg: config.Config{UILanguage: "en"}, date: "2026-07-22"}
	lines := enEmpty.bodyLines(80)
	if len(lines) == 0 || !strings.Contains(lines[0], "no readings for 2026-07-22") {
		t.Errorf("en no-readings bodyLines[0] = %q, want it to contain %q (single space)", lines[0], "no readings for 2026-07-22")
	}
	if strings.Contains(lines[0], "for  2026") {
		t.Errorf("en no-readings bodyLines[0] = %q, has 2+ spaces before the date", lines[0])
	}

	plEmpty := Model{cfg: config.Config{UILanguage: "pl"}, date: "2026-07-22"}
	lines = plEmpty.bodyLines(80)
	if len(lines) == 0 || !strings.Contains(lines[0], "brak czytań na 2026-07-22") {
		t.Errorf("pl no-readings bodyLines[0] = %q, want it to contain %q (single space)", lines[0], "brak czytań na 2026-07-22")
	}

	errText := "boom"
	enErr := Model{cfg: config.Config{UILanguage: "en"}, err: errors.New(errText)}
	lines = enErr.bodyLines(80)
	if len(lines) == 0 || !strings.Contains(lines[0], "error: "+errText) {
		t.Errorf("en error bodyLines[0] = %q, want it to contain %q (single space)", lines[0], "error: "+errText)
	}
	if strings.Contains(lines[0], "error:  ") {
		t.Errorf("en error bodyLines[0] = %q, has 2+ spaces after \"error:\"", lines[0])
	}

	plErr := Model{cfg: config.Config{UILanguage: "pl"}, err: errors.New(errText)}
	lines = plErr.bodyLines(80)
	if len(lines) == 0 || !strings.Contains(lines[0], "błąd: "+errText) {
		t.Errorf("pl error bodyLines[0] = %q, want it to contain %q (single space)", lines[0], "błąd: "+errText)
	}
	if strings.Contains(lines[0], "błąd:  ") {
		t.Errorf("pl error bodyLines[0] = %q, has 2+ spaces after \"błąd:\"", lines[0])
	}
}

// TestBodyLinesLocalisesHeading checks that a modern-lectionary section
// heading's label word follows cfg.UILanguage while the citation stays
// exactly as scraped (render.LocalizeHeading, brief §3b).
func TestBodyLinesLocalisesHeading(t *testing.T) {
	sec := liturgy.Section{Heading: "Ewangelia (J 20, 1. 11-18)", PartID: "ewangelia"}

	en := Model{cfg: config.Config{UILanguage: "en", Lectionary: "new"}, sections: []liturgy.Section{sec}}
	body := strings.Join(en.bodyLines(80), "\n")
	if !strings.Contains(body, "Gospel (J 20, 1. 11-18)") {
		t.Errorf("en bodyLines missing localised heading: %q", body)
	}

	pl := Model{cfg: config.Config{UILanguage: "pl", Lectionary: "new"}, sections: []liturgy.Section{sec}}
	body = strings.Join(pl.bodyLines(80), "\n")
	if !strings.Contains(body, "Ewangelia (J 20, 1. 11-18)") {
		t.Errorf("pl bodyLines missing unchanged heading: %q", body)
	}
}

// TestDayInfoLineShown checks the day-info line (celebration Name, plus
// its temporal Season if any) is rendered under the top header bar when
// the loaded source carries one, and that pageSize grows its chrome
// allowance to account for the extra line.
func TestDayInfoLineShown(t *testing.T) {
	m := Model{
		cfg:     config.Config{UILanguage: "en"},
		date:    "2026-07-22",
		dayInfo: liturgy.DayInfo{Name: "St. Mary Magdalene", Season: "Feria IV after VIII Sunday after Pentecost"},
	}
	out := m.View()
	if !strings.Contains(out, "St. Mary Magdalene") {
		t.Errorf("View() missing day-info name: %q", out)
	}
	if !strings.Contains(out, "Feria IV after VIII Sunday after Pentecost") {
		t.Errorf("View() missing day-info season: %q", out)
	}
	if got := m.headerLines(); got != 2 {
		t.Errorf("headerLines() = %d, want 2 when DayInfo.Name is set", got)
	}
}

// TestDayInfoLineOmittedWhenEmpty checks the header block stays a single
// line (headerLines() == 1) when the source yielded no DayInfo -- e.g. a
// harvested-sigla offline load, which carries citations only.
func TestDayInfoLineOmittedWhenEmpty(t *testing.T) {
	m := Model{cfg: config.Config{UILanguage: "en"}, date: "2026-07-22"}
	if line := m.dayInfoLine(); line != "" {
		t.Errorf("dayInfoLine() = %q, want empty when DayInfo is zero", line)
	}
	if got := m.headerLines(); got != 1 {
		t.Errorf("headerLines() = %d, want 1 when DayInfo is zero", got)
	}
}

// TestFooterKeysLocalised checks the footer keybar text follows
// cfg.UILanguage.
func TestFooterKeysLocalised(t *testing.T) {
	en := Model{cfg: config.Config{UILanguage: "en"}, date: "2026-07-22"}
	if out := en.View(); !strings.Contains(out, "q quit") {
		t.Errorf("en View() footer missing %q: %q", "q quit", out)
	}

	pl := Model{cfg: config.Config{UILanguage: "pl"}, date: "2026-07-22"}
	if out := pl.View(); !strings.Contains(out, "q wyjście") {
		t.Errorf("pl View() footer missing %q: %q", "q wyjście", out)
	}
}

func TestJumpToDate(t *testing.T) {
	send := func(m Model, s string) Model {
		for _, r := range s {
			nm, _ := m.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune{r}})
			m = nm.(Model)
		}
		return m
	}

	m := New(config.Default(), "2026-07-22", "wuj")
	m = send(m, "d")
	if !m.jumping {
		t.Fatal("'d' did not enter jump mode")
	}
	m = send(m, "2026-01-02")
	if m.jumpBuf != "2026-01-02" {
		t.Fatalf("jumpBuf = %q", m.jumpBuf)
	}
	nm, _ := m.Update(tea.KeyMsg{Type: tea.KeyEnter})
	m = nm.(Model)
	if m.jumping {
		t.Error("still in jump mode after Enter")
	}
	if m.date != "2026-01-02" {
		t.Errorf("date = %q, want 2026-01-02", m.date)
	}

	// Esc cancels without changing the date.
	m2 := New(config.Default(), "2026-07-22", "wuj")
	m2 = send(m2, "d")
	m2 = send(m2, "2099")
	nm2, _ := m2.Update(tea.KeyMsg{Type: tea.KeyEsc})
	m2 = nm2.(Model)
	if m2.jumping || m2.jumpBuf != "" || m2.date != "2026-07-22" {
		t.Errorf("esc did not cancel cleanly: jumping=%v buf=%q date=%q", m2.jumping, m2.jumpBuf, m2.date)
	}
}