package compass

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

func TestSetWinsOverPersistedOverrides(t *testing.T) {
	dir := writeConfigTree(t, map[string]string{
		"app.yaml": "name: base\n",
		"env/development/overrides.yaml": "app:\n  name: persisted\n",
	})
	cfg, err := Open(Options{Dir: dir, Env: "development", Environ: []string{}})
	if err != nil {
		t.Fatalf("Open: %v", err)
	}
	if got := cfg.String("app.name"); got != "persisted" {
		t.Fatalf("loaded persisted name = %q, want persisted", got)
	}
	if err := cfg.Set("app.name", "runtime"); err != nil {
		t.Fatalf("Set: %v", err)
	}
	if got := cfg.String("app.name"); got != "runtime" {
		t.Fatalf("Set should win, got %q", got)
	}
}

func TestPersistWritesEnvOverridesAtomicallyWithRestrictivePerms(t *testing.T) {
	dir := writeConfigTree(t, map[string]string{
		"app.yaml": "name: base\n",
	})
	cfg, err := Open(Options{Dir: dir, Env: "development", Environ: []string{}})
	if err != nil {
		t.Fatalf("Open: %v", err)
	}
	if err := cfg.Set("app.name", "saved"); err != nil {
		t.Fatalf("Set: %v", err)
	}
	if err := cfg.Persist(); err != nil {
		t.Fatalf("Persist: %v", err)
	}
	path := filepath.Join(dir, "env", "development", "overrides.yaml")
	info, err := os.Stat(path)
	if err != nil {
		t.Fatalf("stat overrides: %v", err)
	}
	if info.Mode().Perm() != 0o600 {
		t.Fatalf("overrides perm = %o, want 0600", info.Mode().Perm())
	}
	body, err := os.ReadFile(path)
	if err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(string(body), "saved") {
		t.Fatalf("overrides.yaml = %q, want to contain saved", body)
	}
	tmp := filepath.Join(dir, "env", "development", "overrides.yaml.tmp")
	if _, err := os.Stat(tmp); !os.IsNotExist(err) {
		t.Fatalf("temporary persist file should not remain: %v", err)
	}
}

func TestReloadClearsSetAndRereadsFiles(t *testing.T) {
	dir := writeConfigTree(t, map[string]string{
		"app.yaml": "name: base\n",
	})
	cfg, err := Open(Options{Dir: dir, Env: "development", Environ: []string{}})
	if err != nil {
		t.Fatalf("Open: %v", err)
	}
	fsys := fstest.MapFS{
		"config/config.yaml": {Data: []byte("posts_per_page: 10\n")},
	}
	if err := cfg.MergePlugin("golem15.hello", fsys); err != nil {
		t.Fatalf("MergePlugin: %v", err)
	}
	if err := cfg.Set("app.name", "runtime"); err != nil {
		t.Fatalf("Set: %v", err)
	}
	if err := cfg.Persist(); err != nil {
		t.Fatalf("Persist: %v", err)
	}
	if err := cfg.Set("app.name", "runtime2"); err != nil {
		t.Fatalf("Set runtime2: %v", err)
	}
	if err := cfg.Set("golem15.hello.posts_per_page", 99); err != nil {
		t.Fatalf("Set posts: %v", err)
	}
	if err := os.WriteFile(filepath.Join(dir, "app.yaml"), []byte("name: disk\n"), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := cfg.Reload(); err != nil {
		t.Fatalf("Reload: %v", err)
	}
	if got := cfg.String("app.name"); got != "runtime" {
		t.Fatalf("after Reload, name = %q, want persisted runtime (Set cleared)", got)
	}
	if got := cfg.Int("golem15.hello.posts_per_page"); got != 10 {
		t.Fatalf("after Reload, posts_per_page = %d, want plugin default 10", got)
	}
}

func TestPersistRejectsInvalidEnvName(t *testing.T) {
	dir := writeConfigTree(t, map[string]string{
		"app.yaml": "name: base\n",
	})
	_, err := Open(Options{Dir: dir, Env: "../etc", Environ: []string{}})
	if err == nil {
		t.Fatal("expected invalid environment name to fail")
	}
	if strings.Contains(strings.ToLower(err.Error()), "etc") {
		t.Fatalf("error should not echo unsanitized env path: %v", err)
	}
}