// agentconfig 測試 — AB9 範圍。

package agentconfig

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

func TestDefault_MatchesTDD(t *testing.T) {
	d := Default()
	if d.Version != currentSchemaVersion {
		t.Errorf("Version = %d; want %d", d.Version, currentSchemaVersion)
	}
	if d.Relay.URL != DefaultRelayURL {
		t.Errorf("Relay.URL = %q; want %q", d.Relay.URL, DefaultRelayURL)
	}
	if d.Relay.Reconnect != ReconnectAuto {
		t.Errorf("Relay.Reconnect = %q; want auto", d.Relay.Reconnect)
	}
	if d.Behavior.Autostart != false {
		t.Error("Behavior.Autostart should default false")
	}
	if d.Log.Level != LogLevelInfo {
		t.Errorf("Log.Level = %q; want info", d.Log.Level)
	}
}

func TestValidate_AcceptsDefaults(t *testing.T) {
	cfg := Default()
	if err := cfg.Validate(); err != nil {
		t.Errorf("Default should be valid; err = %v", err)
	}
}

func TestValidate_RejectsBadRelayURL(t *testing.T) {
	cases := []string{
		"",
		"http://relay.example.com",
		"https://relay.example.com",
		"relay.example.com",
		"wss",
	}
	for _, url := range cases {
		cfg := Default()
		cfg.Relay.URL = url
		if err := cfg.Validate(); err == nil {
			t.Errorf("Validate should reject Relay.URL=%q", url)
		}
	}
}

func TestValidate_AcceptsWsAndWss(t *testing.T) {
	for _, url := range []string{"ws://localhost:8080/tunnel", "wss://relay.example.com/tunnel/connect"} {
		cfg := Default()
		cfg.Relay.URL = url
		if err := cfg.Validate(); err != nil {
			t.Errorf("Validate should accept %q; err = %v", url, err)
		}
	}
}

func TestValidate_RejectsBadReconnectMode(t *testing.T) {
	cfg := Default()
	cfg.Relay.Reconnect = "never"
	if err := cfg.Validate(); err == nil {
		t.Error("Validate should reject Reconnect=never")
	}
}

func TestValidate_RejectsBadLogLevel(t *testing.T) {
	cfg := Default()
	cfg.Log.Level = "trace"
	if err := cfg.Validate(); err == nil {
		t.Error("Validate should reject Log.Level=trace")
	}
}

func TestValidate_ReportsAllErrors(t *testing.T) {
	cfg := Default()
	cfg.Relay.URL = "bad"
	cfg.Relay.Reconnect = "maybe"
	cfg.Log.Level = "trace"
	err := cfg.Validate()
	if err == nil {
		t.Fatal("Validate should fail on 3 bad fields")
	}
	msg := err.Error()
	for _, needle := range []string{"relay.url", "relay.reconnect", "log.level"} {
		if !strings.Contains(msg, needle) {
			t.Errorf("Validate error should mention %q; got: %s", needle, msg)
		}
	}
}

func TestNewStore_MissingFileUsesDefaults(t *testing.T) {
	dir := t.TempDir()
	s, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore: %v", err)
	}
	cfg := s.Get()
	if cfg.Relay.URL != DefaultRelayURL {
		t.Errorf("missing file should yield default URL; got %q", cfg.Relay.URL)
	}
	// 首次啟動應該把預設值寫下去
	if _, err := os.Stat(s.Path()); err != nil {
		t.Errorf("config.yaml should be created on first launch; stat err = %v", err)
	}
}

func TestNewStore_SaveThenReload(t *testing.T) {
	dir := t.TempDir()
	s1, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore s1: %v", err)
	}
	newCfg := s1.Get()
	newCfg.Relay.URL = "wss://custom.relay.example.com/tunnel"
	newCfg.Relay.Reconnect = ReconnectManual
	newCfg.Behavior.Autostart = true
	newCfg.Log.Level = LogLevelDebug

	if err := s1.Save(newCfg); err != nil {
		t.Fatalf("Save: %v", err)
	}

	// Reopen → 值還在
	s2, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore s2: %v", err)
	}
	got := s2.Get()
	if got.Relay.URL != newCfg.Relay.URL {
		t.Errorf("Relay.URL = %q; want %q", got.Relay.URL, newCfg.Relay.URL)
	}
	if got.Relay.Reconnect != ReconnectManual {
		t.Errorf("Relay.Reconnect = %q; want manual", got.Relay.Reconnect)
	}
	if !got.Behavior.Autostart {
		t.Error("Behavior.Autostart = false; want true")
	}
	if got.Log.Level != LogLevelDebug {
		t.Errorf("Log.Level = %q; want debug", got.Log.Level)
	}
}

func TestNewStore_CorruptYAMLFallsBackToDefaults(t *testing.T) {
	dir := t.TempDir()
	// 先寫一個壞 YAML 檔
	path := filepath.Join(dir, "config.yaml")
	if err := os.WriteFile(path, []byte("relay:\n  url: [this is not valid yaml"), 0o600); err != nil {
		t.Fatalf("write corrupt: %v", err)
	}
	s, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore should not error on corrupt file; got %v", err)
	}
	if s.Get().Relay.URL != DefaultRelayURL {
		t.Errorf("corrupt file should fall back to defaults; got Relay.URL=%q", s.Get().Relay.URL)
	}
}

func TestNewStore_InvalidValuesFallBackToDefaults(t *testing.T) {
	dir := t.TempDir()
	// 合法 YAML 但值非法
	content := `version: 1
relay:
  url: http://bad.example.com
  reconnect: maybe
behavior:
  autostart: false
log:
  level: trace
`
	path := filepath.Join(dir, "config.yaml")
	if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
		t.Fatalf("write: %v", err)
	}
	s, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore: %v", err)
	}
	got := s.Get()
	if got.Relay.URL != DefaultRelayURL || got.Log.Level != DefaultLogLevel {
		t.Errorf("invalid values should fall back to defaults; got %+v", got)
	}
}

func TestSave_RejectsInvalidCfg(t *testing.T) {
	dir := t.TempDir()
	s, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore: %v", err)
	}
	before := s.Get()

	bad := Default()
	bad.Relay.URL = "http://no-websocket-scheme.example.com"
	if err := s.Save(bad); err == nil {
		t.Error("Save should reject invalid URL")
	}
	// 內部狀態不該被改動
	if got := s.Get(); got.Relay.URL != before.Relay.URL {
		t.Errorf("invalid Save should not mutate internal state; got URL=%q", got.Relay.URL)
	}
}

func TestNewStore_PartialYAMLFilled(t *testing.T) {
	dir := t.TempDir()
	// 只寫 relay.url，其他欄位缺失
	content := `relay:
  url: wss://partial.example.com/tunnel
`
	path := filepath.Join(dir, "config.yaml")
	if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
		t.Fatalf("write: %v", err)
	}
	s, err := NewStore(dir, nil)
	if err != nil {
		t.Fatalf("NewStore: %v", err)
	}
	got := s.Get()
	if got.Relay.URL != "wss://partial.example.com/tunnel" {
		t.Errorf("should preserve user URL; got %q", got.Relay.URL)
	}
	if got.Relay.Reconnect != DefaultReconnectMode {
		t.Errorf("should fill missing Reconnect; got %q", got.Relay.Reconnect)
	}
	if got.Log.Level != DefaultLogLevel {
		t.Errorf("should fill missing Log.Level; got %q", got.Log.Level)
	}
}

func TestNewStore_RequiresDataDir(t *testing.T) {
	if _, err := NewStore("", nil); err == nil {
		t.Error("NewStore(\"\") should error")
	}
}