package shared

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

// withConfigDir points XDG_CONFIG_HOME at a temp dir and writes the given
// config file into <tmp>/vcm/<name>, returning the temp base.
func withConfigDir(t *testing.T, name, content string) string {
	t.Helper()
	base := t.TempDir()
	t.Setenv("XDG_CONFIG_HOME", base)
	dir := filepath.Join(base, appDir)
	if err := os.MkdirAll(dir, 0o700); err != nil {
		t.Fatal(err)
	}
	if content != "" {
		if err := os.WriteFile(filepath.Join(dir, name), []byte(content), 0o600); err != nil {
			t.Fatal(err)
		}
	}
	return base
}

const sampleConfig = `
defaults:
  method: ldap
  user: ben
contexts:
  sydney:
    address: https://vault.syd1.au.unkin.net
  staging/sydney:
    address: https://vault-staging.syd1.au.unkin.net
    namespace: staging
    user: svc-ben
  legacy:
    address: https://vault-legacy.example.net
    method: userpass
    path: userpass2
`

func TestLoadAndContextNames(t *testing.T) {
	withConfigDir(t, "config.yaml", sampleConfig)

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	got := cfg.ContextNames()
	want := []string{"legacy", "staging/sydney", "sydney"}
	if len(got) != len(want) {
		t.Fatalf("ContextNames = %v, want %v", got, want)
	}
	for i := range want {
		if got[i] != want[i] {
			t.Fatalf("ContextNames[%d] = %q, want %q (%v)", i, got[i], want[i], got)
		}
	}
	if cfg.Path() == "" {
		t.Error("Path() is empty after loading a config")
	}
}

func TestConfigPath(t *testing.T) {
	base := withConfigDir(t, "config.yaml", sampleConfig)
	if got, want := ConfigPath(), filepath.Join(base, appDir, "config.yaml"); got != want {
		t.Errorf("ConfigPath = %q, want %q", got, want)
	}
}

func TestLoadMissingConfigIsNotError(t *testing.T) {
	t.Setenv("XDG_CONFIG_HOME", t.TempDir())
	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load with no file: %v", err)
	}
	if len(cfg.ContextNames()) != 0 {
		t.Errorf("expected no contexts, got %v", cfg.ContextNames())
	}
}

func TestResolveAppliesDefaults(t *testing.T) {
	withConfigDir(t, "config.yaml", sampleConfig)
	cfg, err := Load()
	if err != nil {
		t.Fatal(err)
	}

	// sydney: inherits method+user from defaults, no namespace, path == method.
	rc, err := cfg.Resolve("sydney")
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != "ldap" || rc.User != "ben" || rc.Namespace != "" || rc.Path != "ldap" {
		t.Errorf("sydney resolved = %+v", rc)
	}

	// staging/sydney: overrides user + namespace, inherits method.
	rc, err = cfg.Resolve("staging/sydney")
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != "ldap" || rc.User != "svc-ben" || rc.Namespace != "staging" {
		t.Errorf("staging/sydney resolved = %+v", rc)
	}

	// legacy: explicit method + custom auth path.
	rc, err = cfg.Resolve("legacy")
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != "userpass" || rc.Path != "userpass2" {
		t.Errorf("legacy resolved = %+v", rc)
	}
}

func TestResolveUnknownContext(t *testing.T) {
	withConfigDir(t, "config.yaml", sampleConfig)
	cfg, _ := Load()
	if _, err := cfg.Resolve("nope"); err == nil {
		t.Error("expected error for unknown context")
	}
}

func TestResolveMethodDefaultWhenUnset(t *testing.T) {
	withConfigDir(t, "config.yaml", `
contexts:
  bare:
    address: https://vault.example.net
`)
	t.Setenv("USER", "alice")
	cfg, _ := Load()
	rc, err := cfg.Resolve("bare")
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != DefaultMethod {
		t.Errorf("method = %q, want %q", rc.Method, DefaultMethod)
	}
	if rc.User != "alice" {
		t.Errorf("user = %q, want alice ($USER fallback)", rc.User)
	}
}

func TestResolveWithOverrides(t *testing.T) {
	withConfigDir(t, "config.yaml", sampleConfig)
	cfg, _ := Load()

	// Overriding the method also moves the auth path (context did not pin one).
	rc, err := cfg.ResolveWithOverrides("sydney", Overrides{Method: "okta", User: "otheruser"})
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != "okta" || rc.Path != "okta" || rc.User != "otheruser" {
		t.Errorf("override resolved = %+v", rc)
	}

	// legacy pins path=userpass2, so a method override must NOT change the path.
	rc, err = cfg.ResolveWithOverrides("legacy", Overrides{Method: "okta"})
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != "okta" || rc.Path != "userpass2" {
		t.Errorf("pinned-path override resolved = %+v", rc)
	}

	// Empty overrides leave resolved values untouched.
	rc, err = cfg.ResolveWithOverrides("sydney", Overrides{})
	if err != nil {
		t.Fatal(err)
	}
	if rc.Method != "ldap" || rc.User != "ben" {
		t.Errorf("no-op override resolved = %+v", rc)
	}
}

func TestResolveOIDC(t *testing.T) {
	withConfigDir(t, "config.yaml", `
contexts:
  admin:
    address: https://vault.example
    method: oidc
    role: admins
  dev:
    address: https://vault.example
    method: oidc
    path: oidc-dev
    oidc_listen: localhost:8251
`)
	cfg, _ := Load()

	rc, err := cfg.Resolve("admin")
	if err != nil {
		t.Fatal(err)
	}
	if rc.Path != "oidc" || rc.Role != "admins" || rc.OIDCListen != DefaultOIDCListen {
		t.Errorf("admin resolved = %+v", rc)
	}

	rc, err = cfg.ResolveWithOverrides("dev", Overrides{Role: "readers"})
	if err != nil {
		t.Fatal(err)
	}
	if rc.Path != "oidc-dev" || rc.Role != "readers" || rc.OIDCListen != "localhost:8251" {
		t.Errorf("dev resolved = %+v", rc)
	}

	rc, _ = cfg.ResolveWithOverrides("admin", Overrides{Listen: "127.0.0.1:9999"})
	if rc.OIDCListen != "127.0.0.1:9999" || rc.Role != "admins" {
		t.Errorf("listen override resolved = %+v", rc)
	}
}