package config

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

func writeConfig(t *testing.T, content string) string {
	t.Helper()
	dir := t.TempDir()
	path := filepath.Join(dir, "netssh.yaml")
	if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
		t.Fatal(err)
	}
	return dir
}

func loadFromDir(t *testing.T, dir string) *Config {
	t.Helper()
	// Override UserConfigDir by pointing viper at our temp dir via env isn't
	// straightforward, so we exercise Load() by temporarily changing XDG_CONFIG_HOME.
	orig := os.Getenv("XDG_CONFIG_HOME")
	os.Setenv("XDG_CONFIG_HOME", dir)
	t.Cleanup(func() { os.Setenv("XDG_CONFIG_HOME", orig) })

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	return cfg
}

func TestLoad_V2TokenVersion_Preserved(t *testing.T) {
	dir := writeConfig(t, `
netbox:
  url: "https://netbox.example.com"
  token: "nbt_abc123"
  token_version: 2
`)
	cfg := loadFromDir(t, dir)
	if cfg.NetBox.TokenVersion != 2 {
		t.Errorf("TokenVersion: got %d, want 2", cfg.NetBox.TokenVersion)
	}
}

func TestLoad_V1TokenVersion_Preserved(t *testing.T) {
	dir := writeConfig(t, `
netbox:
  url: "https://netbox.example.com"
  token: "legacyhex123"
  token_version: 1
`)
	cfg := loadFromDir(t, dir)
	if cfg.NetBox.TokenVersion != 1 {
		t.Errorf("TokenVersion: got %d, want 1", cfg.NetBox.TokenVersion)
	}
}

func TestLoad_AutoDetectsV2_WhenFieldMissing(t *testing.T) {
	dir := writeConfig(t, `
netbox:
  url: "https://netbox.example.com"
  token: "nbt_mytoken"
`)
	cfg := loadFromDir(t, dir)
	if cfg.NetBox.TokenVersion != 2 {
		t.Errorf("TokenVersion: got %d, want 2 (auto-detected from nbt_ prefix)", cfg.NetBox.TokenVersion)
	}
}

func TestLoad_AutoDetectsV1_WhenFieldMissing(t *testing.T) {
	dir := writeConfig(t, `
netbox:
  url: "https://netbox.example.com"
  token: "abc123def456"
`)
	cfg := loadFromDir(t, dir)
	if cfg.NetBox.TokenVersion != 1 {
		t.Errorf("TokenVersion: got %d, want 1 (auto-detected from plain token)", cfg.NetBox.TokenVersion)
	}
}

func TestLoad_TokenVersionZero_WhenNoToken(t *testing.T) {
	dir := writeConfig(t, `
netbox:
  url: "https://netbox.example.com"
`)
	cfg := loadFromDir(t, dir)
	if cfg.NetBox.TokenVersion != 0 {
		t.Errorf("TokenVersion: got %d, want 0 (no token present)", cfg.NetBox.TokenVersion)
	}
}

func TestLoad_Defaults(t *testing.T) {
	dir := writeConfig(t, `
netbox:
  url: "https://netbox.example.com"
  token: "nbt_x"
`)
	cfg := loadFromDir(t, dir)

	if cfg.Cache.TTL != 3600 {
		t.Errorf("default cache.ttl: got %d, want 3600", cfg.Cache.TTL)
	}
	if cfg.Cache.Path == "" {
		t.Error("cache.path should be auto-set when empty")
	}
}

func TestLoad_MissingFile_ReturnsEmptyConfig(t *testing.T) {
	orig := os.Getenv("XDG_CONFIG_HOME")
	os.Setenv("XDG_CONFIG_HOME", t.TempDir()) // dir exists but no netssh.yaml
	defer os.Setenv("XDG_CONFIG_HOME", orig)

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load on missing file should not error: %v", err)
	}
	if cfg.NetBox.URL != "" {
		t.Errorf("expected empty URL, got %q", cfg.NetBox.URL)
	}
}

func TestLoad_InvalidYAML_ReturnsError(t *testing.T) {
	dir := writeConfig(t, "not: valid: yaml: [[[")
	orig := os.Getenv("XDG_CONFIG_HOME")
	os.Setenv("XDG_CONFIG_HOME", dir)
	defer os.Setenv("XDG_CONFIG_HOME", orig)

	_, err := Load()
	if err == nil {
		t.Error("invalid YAML should return an error")
	}
}

func TestPath_ReturnsNonEmpty(t *testing.T) {
	p := Path()
	if p == "" {
		t.Error("Path() should return a non-empty string")
	}
	if filepath.Base(p) != "netssh.yaml" {
		t.Errorf("Path() base: got %q, want netssh.yaml", filepath.Base(p))
	}
}