Initial project skeleton (M0)

Add SPECS.md, JSON config loader with env overrides and validation,
and an empty tview shell with tabs and status bar.

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

internal/config/config_test.go

@@ -0,0 +1,78 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+const valid = `{
+  "radarr":  {"url": "http://localhost:7878/", "apikey": "r"},
+  "sonarr":  {"url": "http://localhost:8989",  "apikey": "s"},
+  "sabnzbd": {"url": "https://sab.example.com", "apikey": "n"}
+}`
+
+func TestParseValid(t *testing.T) {
+	cfg, err := Parse([]byte(valid))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.Radarr.URL != "http://localhost:7878" {
+		t.Errorf("trailing slash not trimmed: %q", cfg.Radarr.URL)
+	}
+	if cfg.UI.RefreshSeconds != defaultRefreshSeconds {
+		t.Errorf("refresh default = %d", cfg.UI.RefreshSeconds)
+	}
+}
+
+func TestParseErrors(t *testing.T) {
+	tests := map[string]struct {
+		json string
+		want string
+	}{
+		"unknown field": {`{"radar": {}}`, "unknown field"},
+		"missing key":   {`{"radarr":{"url":"http://a"},"sonarr":{"url":"http://b","apikey":"x"},"sabnzbd":{"url":"http://c","apikey":"x"}}`, "radarr: apikey is required"},
+		"bad url":       {`{"radarr":{"url":"localhost","apikey":"x"},"sonarr":{"url":"http://b","apikey":"x"},"sabnzbd":{"url":"http://c","apikey":"x"}}`, "must be an http(s) URL"},
+		"invalid json":  {`{`, "parsing config"},
+	}
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			_, err := Parse([]byte(tc.json))
+			if err == nil || !strings.Contains(err.Error(), tc.want) {
+				t.Fatalf("err = %v, want containing %q", err, tc.want)
+			}
+		})
+	}
+}
+
+func TestEnvOverride(t *testing.T) {
+	t.Setenv("ARR_TUI_RADARR_APIKEY", "from-env")
+	cfg, err := Parse([]byte(valid))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.Radarr.APIKey != "from-env" {
+		t.Errorf("apikey = %q", cfg.Radarr.APIKey)
+	}
+}
+
+func TestLoadPermissionWarning(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "config.json")
+	if err := os.WriteFile(path, []byte(valid), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	_, warnings, err := Load(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(warnings) != 1 {
+		t.Fatalf("warnings = %v", warnings)
+	}
+	if err := os.Chmod(path, 0o600); err != nil {
+		t.Fatal(err)
+	}
+	if _, warnings, _ = Load(path); len(warnings) != 0 {
+		t.Fatalf("unexpected warnings: %v", warnings)
+	}
+}