Detail panes: poster top right, title and facts left, plot below; sextant rendering

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

internal/ui/cover_test.go

@@ -94,7 +94,7 @@ func TestQuadCell(t *testing.T) {
 		{"one corner", [4]color.RGBA{red, blue, blue, blue}, '▘', red, blue, false},
 		{"diagonal", [4]color.RGBA{red, black, black, red}, '▞', black, red, false},
 	} {
-		ch, fg, bg := quadCell(tc.px)
+		ch, fg, bg := quadrantStyle.bestCell(tc.px[:])
 		if ch != tc.wantCh || fg != tc.wantFg || bg != tc.wantBg {
 			t.Errorf("%s: %q fg=%v bg=%v, want %q fg=%v bg=%v", tc.name, ch, fg, bg, tc.wantCh, tc.wantFg, tc.wantBg)
 		}
@@ -102,7 +102,7 @@ func TestQuadCell(t *testing.T) {
 	// Nearly flat noise stays a flat cell instead of a distracting pattern.
 	n := color.RGBA{100, 100, 100, 255}
 	m := color.RGBA{102, 100, 101, 255}
-	if ch, _, _ := quadCell([4]color.RGBA{n, m, n, n}); ch != ' ' {
+	if ch, _, _ := quadrantStyle.bestCell([]color.RGBA{n, m, n, n}); ch != ' ' {
 		t.Errorf("noise rendered as %q", ch)
 	}
 }
@@ -127,7 +127,7 @@ func TestCoverViewDraws(t *testing.T) {
 	defer screen.Fini()
 	screen.SetSize(30, 10)
 
-	c := newCoverView()
+	c := newCoverView(quadrantStyle)
 	c.setImage(stripes(40, 60)) // red above blue
 	c.SetRect(0, 0, 30, 10)     // fits 13 columns × 10 rows
 
@@ -142,14 +142,15 @@ func TestCoverViewDraws(t *testing.T) {
 		return ch, rgba(fg), rgba(bg)
 	}
 	red, blue := color.RGBA{255, 0, 0, 255}, color.RGBA{0, 0, 255, 255}
-	if _, fg, bg := cell(0, 0); fg != red || bg != red {
+	// The poster is 13 columns wide and sits against the right edge (x 17..29).
+	if _, fg, bg := cell(17, 0); fg != red || bg != red {
 		t.Errorf("top row = fg %v bg %v, want red", fg, bg)
 	}
-	if _, fg, bg := cell(12, 9); fg != blue || bg != blue {
+	if _, fg, bg := cell(29, 9); fg != blue || bg != blue {
 		t.Errorf("bottom right = fg %v bg %v, want blue", fg, bg)
 	}
-	// Outside the poster's footprint nothing is drawn.
-	if ch, _, _, _ := screen.GetContent(13, 0); ch != ' ' {
+	// Left of the poster's footprint nothing is drawn.
+	if ch, _, _, _ := screen.GetContent(16, 0); ch != ' ' {
 		t.Errorf("poster stretched beyond its aspect ratio: %q", ch)
 	}
 }
@@ -188,3 +189,58 @@ func TestLoadCoverRemembersFailures(t *testing.T) {
 		t.Error("expected an error for a recently failed cover")
 	}
 }
+
+func TestSextantGlyphs(t *testing.T) {
+	seen := map[rune]int{}
+	for mask := 0; mask < 64; mask++ {
+		r := sextantGlyph(mask)
+		if prev, dup := seen[r]; dup {
+			t.Fatalf("masks %d and %d share the glyph %q", prev, mask, r)
+		}
+		seen[r] = mask
+		if mask > 0 && mask < 63 && mask != 21 && mask != 42 && (r < 0x1FB00 || r > 0x1FB3B) {
+			t.Errorf("mask %d: %U outside the sextant block", mask, r)
+		}
+	}
+	for mask, want := range map[int]rune{1: 0x1FB00, 2: 0x1FB01, 20: 0x1FB13, 22: 0x1FB14, 43: 0x1FB28, 62: 0x1FB3B, 21: '▌', 42: '▐', 63: '█', 0: ' '} {
+		if got := sextantGlyph(mask); got != want {
+			t.Errorf("sextantGlyph(%d) = %U, want %U", mask, got, want)
+		}
+	}
+}
+
+func TestSextantCell(t *testing.T) {
+	red, blue := color.RGBA{255, 0, 0, 255}, color.RGBA{0, 0, 255, 255}
+	// Two rows of red above one row of blue.
+	ch, fg, bg := sextantStyle.bestCell([]color.RGBA{red, red, red, red, blue, blue})
+	if ch != sextantGlyph(15) || fg != red || bg != blue {
+		t.Errorf("got %U fg=%v bg=%v", ch, fg, bg)
+	}
+	// One row each: red, blue, red.
+	ch, fg, bg = sextantStyle.bestCell([]color.RGBA{red, red, blue, blue, red, red})
+	if ch != sextantGlyph(0b001100) || fg != blue || bg != red {
+		t.Errorf("three bands: %U fg=%v bg=%v", ch, fg, bg)
+	}
+}
+
+func TestCoverStyleFor(t *testing.T) {
+	env := func(m map[string]string) func(string) string { return func(k string) string { return m[k] } }
+	for _, tc := range []struct {
+		setting string
+		env     map[string]string
+		want    string
+	}{
+		{"auto", map[string]string{"TERM": "xterm-kitty"}, "sextant"},
+		{"", map[string]string{"TERM_PROGRAM": "WezTerm"}, "sextant"},
+		{"auto", map[string]string{"TERM": "foot"}, "sextant"},
+		{"auto", map[string]string{"KITTY_WINDOW_ID": "3", "TERM": "screen"}, "sextant"},
+		{"auto", map[string]string{"TERM": "xterm-256color"}, "quadrant"},
+		{"auto", nil, "quadrant"},
+		{"quadrant", map[string]string{"TERM": "xterm-kitty"}, "quadrant"},
+		{"sextant", nil, "sextant"},
+	} {
+		if got := coverStyleFor(tc.setting, env(tc.env)).name; got != tc.want {
+			t.Errorf("%q %v = %s, want %s", tc.setting, tc.env, got, tc.want)
+		}
+	}
+}