package app

import (
	"os"
	"path/filepath"
	"strings"
	"testing"

	tea "github.com/charmbracelet/bubbletea"
)

func typeInto(a *App, s string) {
	for _, r := range s {
		a.Update(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune{r}})
	}
}

func TestCtrlNOpensNamePrompt(t *testing.T) {
	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN})
	if a.mode != ModeNamePrompt {
		t.Fatalf("mode = %d, want ModeNamePrompt", a.mode)
	}
	if a.dialog.Title() != "New note" {
		t.Errorf("dialog title = %q, want 'New note'", a.dialog.Title())
	}
}

func TestNamePromptShowsTargetDir(t *testing.T) {
	dir := t.TempDir()
	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	a.openNamePrompt(namingNew, dir, "")
	if !strings.Contains(a.View(), filepath.Base(dir)) {
		t.Errorf("View() does not show the target dir %q:\n%s", dir, a.View())
	}
}

func TestEscCancelsBackToPreviousMode(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "open.md")
	os.WriteFile(p, []byte("body"), 0o644)

	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	a.Load(p)
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN})
	a.Update(tea.KeyMsg{Type: tea.KeyEsc})
	if a.mode != ModeEditor {
		t.Errorf("mode = %d after Esc, want ModeEditor", a.mode)
	}
	if a.path != p {
		t.Errorf("path = %q after Esc, want the file we were editing (%q)", a.path, p)
	}
	entries, _ := os.ReadDir(dir)
	if len(entries) != 1 {
		t.Errorf("Esc wrote %d entries to disk, want 1 (the pre-existing file)", len(entries))
	}
}

func TestDirtyBufferConfirmsDiscardBeforePrompt(t *testing.T) {
	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	a.editor.SetContent([]byte("x"))
	a.editor.Dirty = true
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN})
	if a.mode == ModeNamePrompt {
		t.Fatal("first Ctrl+N on a dirty buffer opened the prompt; want a discard confirmation")
	}
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN})
	if a.mode != ModeNamePrompt {
		t.Errorf("second Ctrl+N: mode = %d, want ModeNamePrompt", a.mode)
	}
}

func TestPickerCtrlNPrefillsQuery(t *testing.T) {
	dir := t.TempDir()
	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	if err := a.StartPickerIn(dir); err != nil {
		t.Fatal(err)
	}
	typeInto(a, "draft")
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN})
	if a.mode != ModeNamePrompt {
		t.Fatalf("mode = %d, want ModeNamePrompt", a.mode)
	}
	if a.dialog.Value() != "draft" {
		t.Errorf("dialog prefill = %q, want draft", a.dialog.Value())
	}
}

func TestF2OpensRenamePrefilled(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "before.md")
	os.WriteFile(p, []byte("body"), 0o644)

	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	a.Load(p)
	a.Update(tea.KeyMsg{Type: tea.KeyF2})
	if a.mode != ModeNamePrompt {
		t.Fatalf("mode = %d, want ModeNamePrompt", a.mode)
	}
	if a.dialog.Title() != "Rename" {
		t.Errorf("dialog title = %q, want Rename", a.dialog.Title())
	}
	if a.dialog.Value() != "before" {
		t.Errorf("dialog prefill = %q, want before", a.dialog.Value())
	}
}

func TestReentrantCtrlNDoesNotTrapTheDialog(t *testing.T) {
	dir := t.TempDir()
	a := newApp()
	a.Update(tea.WindowSizeMsg{Width: 100, Height: 20})
	a.saveDir = dir
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN})
	a.Update(tea.KeyMsg{Type: tea.KeyCtrlN}) // re-press while the prompt is open
	if a.prevMode == ModeNamePrompt {
		t.Fatal("prevMode became ModeNamePrompt; Esc would be a no-op")
	}
	a.Update(tea.KeyMsg{Type: tea.KeyEsc})
	if a.mode == ModeNamePrompt {
		t.Error("Esc left the app in ModeNamePrompt; the dialog is inescapable")
	}
}

func TestDirLabelDoesNotCollapseSiblingSharingHomePrefix(t *testing.T) {
	home, err := os.UserHomeDir()
	if err != nil || home == "" {
		t.Skip("no $HOME to test against")
	}
	a := newApp()
	sibling := home + "bar" // shares home's string prefix but is not under it
	if got := a.dirLabel(sibling); strings.HasPrefix(got, "~") {
		t.Errorf("dirLabel(%q) = %q, want no ~ collapse for a sibling directory", sibling, got)
	}
}