package config

import (
	"strconv"
	"strings"
	"testing"
	"time"
)

func TestLoadDefaults(t *testing.T) {
	clearEnvironment(t)

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if cfg.HTTPAddress != ":8080" {
		t.Fatalf("HTTPAddress = %q, want %q", cfg.HTTPAddress, ":8080")
	}
	if cfg.SuperAgent.Enabled {
		t.Fatal("SuperAgent.Enabled = true, want false")
	}
	if cfg.SuperAgent.ConnectTimeout != 15*time.Second {
		t.Fatalf("ConnectTimeout = %v, want 15s", cfg.SuperAgent.ConnectTimeout)
	}
	if cfg.SuperAgent.RecoveryMaxAttempts != 5 {
		t.Fatalf("RecoveryMaxAttempts = %d, want 5", cfg.SuperAgent.RecoveryMaxAttempts)
	}
	if cfg.SuperAgent.RecoveryInitialBackoff != 250*time.Millisecond {
		t.Fatalf("RecoveryInitialBackoff = %v, want 250ms", cfg.SuperAgent.RecoveryInitialBackoff)
	}
	if cfg.SuperAgent.MaxMessageBytes != 64*1024 {
		t.Fatalf("MaxMessageBytes = %d, want %d", cfg.SuperAgent.MaxMessageBytes, 64*1024)
	}
	if cfg.SuperAgent.ProbeSubjectID != "fire-safety-ymd-connectivity-probe" {
		t.Fatalf("ProbeSubjectID = %q", cfg.SuperAgent.ProbeSubjectID)
	}
	if cfg.SuperAgent.ProbeTimeout != 10*time.Minute {
		t.Fatalf("ProbeTimeout = %v, want 10m", cfg.SuperAgent.ProbeTimeout)
	}
	if cfg.Chat.Enabled {
		t.Fatal("Chat.Enabled = true, want false")
	}
	if cfg.Chat.PageEnabled {
		t.Fatal("Chat.PageEnabled = true, want false")
	}
	if cfg.Chat.AllowLegacyShortToken {
		t.Fatal("Chat.AllowLegacyShortToken = true, want false")
	}
	if cfg.Chat.SubjectID != "fire-safety-ymd-chat-test-subject" || cfg.Chat.MaxBodyBytes != 128*1024 ||
		cfg.Chat.CompatAppID != "" || cfg.Chat.RunTimeout != 10*time.Minute || cfg.Chat.SessionTTL != 30*time.Minute || cfg.Chat.MaxSessions != 1000 {
		t.Fatalf("unexpected Chat defaults: %#v", cfg.Chat)
	}
	if cfg.MCP.Enabled || cfg.PostGIS.Enabled {
		t.Fatalf("MCP/PostGIS must be disabled by default: MCP=%v PostGIS=%v", cfg.MCP.Enabled, cfg.PostGIS.Enabled)
	}
	if cfg.MCP.MaxBodyBytes != 256*1024 || cfg.MCP.ToolTimeout != 5*time.Second {
		t.Fatalf("unexpected MCP defaults: %#v", cfg.MCP)
	}
	if cfg.MCP.ScopeMode != MCPScopeModeTownAllowlist {
		t.Fatalf("MCP.ScopeMode = %q, want %q", cfg.MCP.ScopeMode, MCPScopeModeTownAllowlist)
	}
	if cfg.PostGIS.ConnectTimeout != 5*time.Second || cfg.PostGIS.QueryTimeout != 3*time.Second || cfg.PostGIS.MaxConns != 4 {
		t.Fatalf("unexpected PostGIS defaults: %#v", cfg.PostGIS)
	}
}

func TestLoadConfiguredChat(t *testing.T) {
	clearEnvironment(t)
	t.Setenv(SuperAgentEnabledEnv, "true")
	t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
	t.Setenv(SuperAgentOpenAPIKeyEnv, "superagent-test-open-api-key")
	t.Setenv(ChatEnabledEnv, "true")
	t.Setenv(ChatPageEnabledEnv, "true")
	t.Setenv(ChatAuthTokenEnv, "0123456789abcdef0123456789abcdef")
	t.Setenv(ChatSubjectIDEnv, " local-chat-test-subject ")
	t.Setenv(ChatCompatAppIDEnv, " fire-safety-public-app ")
	t.Setenv(ChatAllowedOriginsEnv, " http://localhost:5173/,https://fire.example.test,http://localhost:5173 ")
	t.Setenv(ChatMaxBodyBytesEnv, "8192")
	t.Setenv(ChatRunTimeoutEnv, "2m")
	t.Setenv(ChatSessionTTLEnv, "45m")
	t.Setenv(ChatMaxSessionsEnv, "50")

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if !cfg.Chat.Enabled || !cfg.Chat.PageEnabled || cfg.Chat.AuthToken == "" || cfg.Chat.SubjectID != "local-chat-test-subject" || cfg.Chat.CompatAppID != "fire-safety-public-app" {
		t.Fatalf("unexpected Chat config: %#v", cfg.Chat)
	}
	if got, want := strings.Join(cfg.Chat.AllowedOrigins, ","), "http://localhost:5173,https://fire.example.test"; got != want {
		t.Fatalf("AllowedOrigins = %q, want %q", got, want)
	}
	if cfg.Chat.MaxBodyBytes != 8192 || cfg.Chat.RunTimeout != 2*time.Minute || cfg.Chat.SessionTTL != 45*time.Minute || cfg.Chat.MaxSessions != 50 {
		t.Fatalf("unexpected Chat limits: %#v", cfg.Chat)
	}
}

func TestLoadConfiguredMCPAndPostGIS(t *testing.T) {
	clearEnvironment(t)
	t.Setenv(MCPEnabledEnv, "true")
	t.Setenv(MCPAuthTokenEnv, "0123456789abcdef0123456789abcdef")
	t.Setenv(MCPScopeModeEnv, " TOWN_ALLOWLIST ")
	t.Setenv(MCPAllowedTownsEnv, " 莒格庄镇, 高陵镇,莒格庄镇 ")
	t.Setenv(MCPMaxBodyBytesEnv, "4096")
	t.Setenv(MCPToolTimeoutEnv, "7s")
	t.Setenv(PostGISEnabledEnv, "true")
	t.Setenv(PostGISDSNEnv, "postgresql://fire:secret@127.0.0.1:5432/fire_safety?sslmode=disable")
	t.Setenv(PostGISExpectedSRIDEnv, "4326")
	t.Setenv(PostGISConnectTimeoutEnv, "2s")
	t.Setenv(PostGISQueryTimeoutEnv, "4s")
	t.Setenv(PostGISMaxConnsEnv, "6")

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if !cfg.MCP.Enabled || cfg.MCP.AuthToken == "" || cfg.MCP.MaxBodyBytes != 4096 || cfg.MCP.ToolTimeout != 7*time.Second {
		t.Fatalf("unexpected MCP config: %#v", cfg.MCP)
	}
	if cfg.MCP.ScopeMode != MCPScopeModeTownAllowlist {
		t.Fatalf("MCP.ScopeMode = %q, want %q", cfg.MCP.ScopeMode, MCPScopeModeTownAllowlist)
	}
	if got, want := strings.Join(cfg.MCP.AllowedTowns, ","), "莒格庄镇,高陵镇"; got != want {
		t.Fatalf("AllowedTowns = %q, want %q", got, want)
	}
	if !cfg.PostGIS.Enabled || cfg.PostGIS.ExpectedSRID != 4326 || cfg.PostGIS.ConnectTimeout != 2*time.Second || cfg.PostGIS.QueryTimeout != 4*time.Second || cfg.PostGIS.MaxConns != 6 {
		t.Fatalf("unexpected PostGIS config: %#v", cfg.PostGIS)
	}
}

func TestLoadConfiguredMCPAllScopeWithoutTownEnumeration(t *testing.T) {
	clearEnvironment(t)
	t.Setenv(MCPEnabledEnv, "true")
	t.Setenv(MCPAuthTokenEnv, "0123456789abcdef0123456789abcdef")
	t.Setenv(MCPScopeModeEnv, "all")
	t.Setenv(PostGISEnabledEnv, "true")
	t.Setenv(PostGISDSNEnv, "postgresql://fire:secret@127.0.0.1:5432/fire_safety?sslmode=disable")
	t.Setenv(PostGISExpectedSRIDEnv, "4326")

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if cfg.MCP.ScopeMode != MCPScopeModeAll {
		t.Fatalf("MCP.ScopeMode = %q, want %q", cfg.MCP.ScopeMode, MCPScopeModeAll)
	}
	if len(cfg.MCP.AllowedTowns) != 0 {
		t.Fatalf("AllowedTowns = %#v, want empty in all scope", cfg.MCP.AllowedTowns)
	}
}

func TestLoadRejectsAllScopeWithTownAllowlist(t *testing.T) {
	clearEnvironment(t)
	t.Setenv(MCPEnabledEnv, "true")
	t.Setenv(MCPAuthTokenEnv, "0123456789abcdef0123456789abcdef")
	t.Setenv(MCPScopeModeEnv, "all")
	t.Setenv(MCPAllowedTownsEnv, "莒格庄镇")

	_, err := Load()
	if err == nil || !strings.Contains(err.Error(), MCPAllowedTownsEnv) {
		t.Fatalf("Load() error = %v, want ambiguous scope rejection", err)
	}
}

func TestLoadConfiguredValues(t *testing.T) {
	clearEnvironment(t)
	t.Setenv(HTTPAddressEnv, " 127.0.0.1:9090 ")
	t.Setenv(SuperAgentEnabledEnv, "true")
	t.Setenv(SuperAgentBaseURLEnv, " https://superagent.example.test/root/ ")
	t.Setenv(SuperAgentOpenAPIKeyEnv, " test-open-api-key ")
	t.Setenv(SuperAgentConnectTimeoutEnv, "3s")
	t.Setenv(SuperAgentRecoveryMaxAttemptsEnv, "2")
	t.Setenv(SuperAgentRecoveryInitialBackoffEnv, "20ms")
	t.Setenv(SuperAgentMaxMessageBytesEnv, "4096")
	t.Setenv(SuperAgentProbeSubjectIDEnv, " probe-user ")
	t.Setenv(SuperAgentProbeTimeoutEnv, "30s")

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if cfg.HTTPAddress != "127.0.0.1:9090" || !cfg.SuperAgent.Enabled {
		t.Fatalf("unexpected base config: %#v", cfg)
	}
	if cfg.SuperAgent.BaseURL != "https://superagent.example.test/root" {
		t.Fatalf("BaseURL = %q", cfg.SuperAgent.BaseURL)
	}
	if cfg.SuperAgent.OpenAPIKey != "test-open-api-key" {
		t.Fatal("OpenAPIKey was not loaded")
	}
	if cfg.SuperAgent.ConnectTimeout != 3*time.Second || cfg.SuperAgent.RecoveryMaxAttempts != 2 || cfg.SuperAgent.RecoveryInitialBackoff != 20*time.Millisecond {
		t.Fatalf("unexpected recovery config: %#v", cfg.SuperAgent)
	}
	if cfg.SuperAgent.MaxMessageBytes != 4096 || cfg.SuperAgent.ProbeSubjectID != "probe-user" || cfg.SuperAgent.ProbeTimeout != 30*time.Second {
		t.Fatalf("unexpected probe config: %#v", cfg.SuperAgent)
	}
}

func TestLoadRejectsInvalidValues(t *testing.T) {
	tests := []struct {
		name  string
		key   string
		value string
	}{
		{name: "boolean", key: SuperAgentEnabledEnv, value: "sometimes"},
		{name: "connect timeout syntax", key: SuperAgentConnectTimeoutEnv, value: "soon"},
		{name: "connect timeout non-positive", key: SuperAgentConnectTimeoutEnv, value: "0s"},
		{name: "recovery attempts syntax", key: SuperAgentRecoveryMaxAttemptsEnv, value: "many"},
		{name: "recovery attempts negative", key: SuperAgentRecoveryMaxAttemptsEnv, value: "-1"},
		{name: "recovery attempts too large", key: SuperAgentRecoveryMaxAttemptsEnv, value: "21"},
		{name: "recovery backoff syntax", key: SuperAgentRecoveryInitialBackoffEnv, value: "later"},
		{name: "recovery backoff non-positive", key: SuperAgentRecoveryInitialBackoffEnv, value: "0s"},
		{name: "message bytes syntax", key: SuperAgentMaxMessageBytesEnv, value: "large"},
		{name: "message bytes non-positive", key: SuperAgentMaxMessageBytesEnv, value: "0"},
		{name: "message bytes too large", key: SuperAgentMaxMessageBytesEnv, value: "16777217"},
		{name: "probe timeout syntax", key: SuperAgentProbeTimeoutEnv, value: "forever"},
		{name: "probe timeout non-positive", key: SuperAgentProbeTimeoutEnv, value: "0s"},
		{name: "Chat boolean", key: ChatEnabledEnv, value: "sometimes"},
		{name: "Chat page boolean", key: ChatPageEnabledEnv, value: "sometimes"},
		{name: "Chat legacy short token boolean", key: ChatAllowLegacyShortTokenEnv, value: "sometimes"},
		{name: "Chat body syntax", key: ChatMaxBodyBytesEnv, value: "large"},
		{name: "Chat body non-positive", key: ChatMaxBodyBytesEnv, value: "0"},
		{name: "Chat body too large", key: ChatMaxBodyBytesEnv, value: "1048577"},
		{name: "Chat run timeout syntax", key: ChatRunTimeoutEnv, value: "forever"},
		{name: "Chat run timeout too large", key: ChatRunTimeoutEnv, value: "31m"},
		{name: "Chat session TTL non-positive", key: ChatSessionTTLEnv, value: "0s"},
		{name: "Chat session TTL too large", key: ChatSessionTTLEnv, value: "25h"},
		{name: "Chat session capacity syntax", key: ChatMaxSessionsEnv, value: "many"},
		{name: "Chat session capacity too large", key: ChatMaxSessionsEnv, value: "10001"},
		{name: "Chat invalid origin", key: ChatAllowedOriginsEnv, value: "https://fire.example.test/path"},
		{name: "Chat wildcard origin", key: ChatAllowedOriginsEnv, value: "*"},
		{name: "Chat invalid subject", key: ChatSubjectIDEnv, value: "subject\nvalue"},
		{name: "Chat invalid compatibility app ID", key: ChatCompatAppIDEnv, value: "invalid/app/id"},
		{name: "MCP boolean", key: MCPEnabledEnv, value: "sometimes"},
		{name: "MCP scope mode", key: MCPScopeModeEnv, value: "automatic"},
		{name: "MCP body syntax", key: MCPMaxBodyBytesEnv, value: "large"},
		{name: "MCP body non-positive", key: MCPMaxBodyBytesEnv, value: "0"},
		{name: "MCP body too large", key: MCPMaxBodyBytesEnv, value: "1048577"},
		{name: "MCP timeout syntax", key: MCPToolTimeoutEnv, value: "soon"},
		{name: "MCP timeout too large", key: MCPToolTimeoutEnv, value: "31s"},
		{name: "PostGIS boolean", key: PostGISEnabledEnv, value: "sometimes"},
		{name: "PostGIS SRID syntax", key: PostGISExpectedSRIDEnv, value: "wgs84"},
		{name: "PostGIS SRID negative", key: PostGISExpectedSRIDEnv, value: "-1"},
		{name: "PostGIS connect timeout", key: PostGISConnectTimeoutEnv, value: "31s"},
		{name: "PostGIS query timeout", key: PostGISQueryTimeoutEnv, value: "0s"},
		{name: "PostGIS max conns syntax", key: PostGISMaxConnsEnv, value: "many"},
		{name: "PostGIS max conns too large", key: PostGISMaxConnsEnv, value: "21"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			clearEnvironment(t)
			t.Setenv(tt.key, tt.value)

			_, err := Load()
			if err == nil || !strings.Contains(err.Error(), tt.key) {
				t.Fatalf("Load() error = %v, want error mentioning %s", err, tt.key)
			}
		})
	}
}

func TestLoadRequiresChatPageDependencies(t *testing.T) {
	configureEnabledChat := func(t *testing.T) {
		t.Helper()
		t.Setenv(SuperAgentEnabledEnv, "true")
		t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
		t.Setenv(SuperAgentOpenAPIKeyEnv, "superagent-open-api-key")
		t.Setenv(ChatEnabledEnv, "true")
		t.Setenv(ChatAuthTokenEnv, "0123456789abcdef0123456789abcdef")
	}

	tests := []struct {
		name       string
		configure  func(*testing.T)
		wantErrKey string
	}{
		{
			name: "chat disabled",
			configure: func(t *testing.T) {
				t.Setenv(ChatCompatAppIDEnv, "fire-safety-app")
				t.Setenv(ChatAllowedOriginsEnv, "https://fire.example.test")
			},
			wantErrKey: ChatEnabledEnv,
		},
		{
			name: "missing compatibility app ID",
			configure: func(t *testing.T) {
				configureEnabledChat(t)
				t.Setenv(ChatAllowedOriginsEnv, "https://fire.example.test")
			},
			wantErrKey: ChatCompatAppIDEnv,
		},
		{
			name: "missing allowed origin",
			configure: func(t *testing.T) {
				configureEnabledChat(t)
				t.Setenv(ChatCompatAppIDEnv, "fire-safety-app")
			},
			wantErrKey: ChatAllowedOriginsEnv,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			clearEnvironment(t)
			t.Setenv(ChatPageEnabledEnv, "true")
			tt.configure(t)

			_, err := Load()
			if err == nil || !strings.Contains(err.Error(), tt.wantErrKey) {
				t.Fatalf("Load() error = %v, want error mentioning %s", err, tt.wantErrKey)
			}
		})
	}
}

func TestLoadRequiresEnabledChatSettings(t *testing.T) {
	tests := []struct {
		name       string
		configure  func(*testing.T)
		wantErrKey string
	}{
		{
			name: "missing chat token",
			configure: func(t *testing.T) {
				t.Setenv(SuperAgentEnabledEnv, "true")
				t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
				t.Setenv(SuperAgentOpenAPIKeyEnv, "superagent-open-api-key")
			},
			wantErrKey: ChatAuthTokenEnv,
		},
		{
			name: "SuperAgent disabled",
			configure: func(t *testing.T) {
				t.Setenv(ChatAuthTokenEnv, "0123456789abcdef0123456789abcdef")
			},
			wantErrKey: SuperAgentEnabledEnv,
		},
		{
			name: "reused SuperAgent key",
			configure: func(t *testing.T) {
				shared := "0123456789abcdef0123456789abcdef"
				t.Setenv(SuperAgentEnabledEnv, "true")
				t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
				t.Setenv(SuperAgentOpenAPIKeyEnv, shared)
				t.Setenv(ChatAuthTokenEnv, shared)
			},
			wantErrKey: ChatAuthTokenEnv,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			clearEnvironment(t)
			t.Setenv(ChatEnabledEnv, "true")
			tt.configure(t)

			_, err := Load()
			if err == nil || !strings.Contains(err.Error(), tt.wantErrKey) {
				t.Fatalf("Load() error = %v, want error mentioning %s", err, tt.wantErrKey)
			}
		})
	}
}

func TestLoadChatLegacyShortTokenPolicy(t *testing.T) {
	configureChat := func(t *testing.T, token string, allowLegacy bool) {
		t.Helper()
		t.Setenv(SuperAgentEnabledEnv, "true")
		t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
		t.Setenv(SuperAgentOpenAPIKeyEnv, "different-superagent-open-api-key")
		t.Setenv(ChatEnabledEnv, "true")
		t.Setenv(ChatAuthTokenEnv, token)
		t.Setenv(ChatAllowLegacyShortTokenEnv, strconv.FormatBool(allowLegacy))
	}

	t.Run("default rejects short token", func(t *testing.T) {
		clearEnvironment(t)
		configureChat(t, "delivered-key", false)
		if _, err := Load(); err == nil || !strings.Contains(err.Error(), ChatAuthTokenEnv) {
			t.Fatalf("Load() error = %v, want short token rejection", err)
		}
	})

	t.Run("explicit compatibility allows short token", func(t *testing.T) {
		clearEnvironment(t)
		configureChat(t, "delivered-key", true)
		cfg, err := Load()
		if err != nil {
			t.Fatalf("Load() error = %v", err)
		}
		if !cfg.Chat.AllowLegacyShortToken || cfg.Chat.AuthToken != "delivered-key" {
			t.Fatalf("unexpected Chat config: %#v", cfg.Chat)
		}
	})

	for _, tt := range []struct {
		name  string
		token string
	}{
		{name: "empty", token: ""},
		{name: "space", token: "delivered key"},
		{name: "control character", token: "delivered\tkey"},
		{name: "Unicode", token: "delivered密钥"},
		{name: "oversized", token: strings.Repeat("a", 4097)},
	} {
		t.Run("compatibility rejects "+tt.name, func(t *testing.T) {
			clearEnvironment(t)
			configureChat(t, tt.token, true)
			if _, err := Load(); err == nil || !strings.Contains(err.Error(), ChatAuthTokenEnv) {
				t.Fatalf("Load() error = %v, want unsafe token rejection", err)
			}
		})
	}
}

func TestLoadRequiresEnabledMCPSettings(t *testing.T) {
	validToken := "0123456789abcdef0123456789abcdef"
	validDSN := "postgresql://fire:secret@127.0.0.1:5432/fire_safety?sslmode=disable"
	tests := []struct {
		name       string
		configure  func(*testing.T)
		wantErrKey string
	}{
		{
			name: "missing token",
			configure: func(t *testing.T) {
				t.Setenv(MCPAllowedTownsEnv, "莒格庄镇")
			},
			wantErrKey: MCPAuthTokenEnv,
		},
		{
			name: "short token",
			configure: func(t *testing.T) {
				t.Setenv(ChatAllowLegacyShortTokenEnv, "true")
				t.Setenv(MCPAuthTokenEnv, "short-token")
				t.Setenv(MCPAllowedTownsEnv, "莒格庄镇")
			},
			wantErrKey: MCPAuthTokenEnv,
		},
		{
			name: "missing scope",
			configure: func(t *testing.T) {
				t.Setenv(MCPAuthTokenEnv, validToken)
			},
			wantErrKey: MCPAllowedTownsEnv,
		},
		{
			name: "PostGIS disabled",
			configure: func(t *testing.T) {
				t.Setenv(MCPAuthTokenEnv, validToken)
				t.Setenv(MCPAllowedTownsEnv, "莒格庄镇")
			},
			wantErrKey: PostGISEnabledEnv,
		},
		{
			name: "missing expected SRID",
			configure: func(t *testing.T) {
				t.Setenv(MCPAuthTokenEnv, validToken)
				t.Setenv(MCPAllowedTownsEnv, "莒格庄镇")
				t.Setenv(PostGISEnabledEnv, "true")
				t.Setenv(PostGISDSNEnv, validDSN)
			},
			wantErrKey: PostGISExpectedSRIDEnv,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			clearEnvironment(t)
			t.Setenv(MCPEnabledEnv, "true")
			tt.configure(t)

			_, err := Load()
			if err == nil || !strings.Contains(err.Error(), tt.wantErrKey) {
				t.Fatalf("Load() error = %v, want error mentioning %s", err, tt.wantErrKey)
			}
		})
	}
}

func TestLoadRejectsReusedSuperAgentAndMCPToken(t *testing.T) {
	clearEnvironment(t)
	sharedToken := "0123456789abcdef0123456789abcdef"
	t.Setenv(SuperAgentEnabledEnv, "true")
	t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
	t.Setenv(SuperAgentOpenAPIKeyEnv, sharedToken)
	t.Setenv(MCPEnabledEnv, "true")
	t.Setenv(MCPAuthTokenEnv, sharedToken)
	t.Setenv(MCPAllowedTownsEnv, "莒格庄镇")
	t.Setenv(PostGISEnabledEnv, "true")
	t.Setenv(PostGISDSNEnv, "postgresql://fire:secret@127.0.0.1:5432/fire_safety?sslmode=disable")
	t.Setenv(PostGISExpectedSRIDEnv, "4326")

	_, err := Load()
	if err == nil || !strings.Contains(err.Error(), MCPAuthTokenEnv) {
		t.Fatalf("Load() error = %v, want token reuse rejection", err)
	}
}

func TestLoadRejectsReusedChatAndMCPToken(t *testing.T) {
	clearEnvironment(t)
	sharedToken := "0123456789abcdef0123456789abcdef"
	t.Setenv(SuperAgentEnabledEnv, "true")
	t.Setenv(SuperAgentBaseURLEnv, "https://superagent.example.test")
	t.Setenv(SuperAgentOpenAPIKeyEnv, "different-superagent-open-api-key")
	t.Setenv(ChatEnabledEnv, "true")
	t.Setenv(ChatAuthTokenEnv, sharedToken)
	t.Setenv(MCPEnabledEnv, "true")
	t.Setenv(MCPAuthTokenEnv, sharedToken)
	t.Setenv(MCPScopeModeEnv, "all")
	t.Setenv(PostGISEnabledEnv, "true")
	t.Setenv(PostGISDSNEnv, "postgresql://fire:secret@127.0.0.1:5432/fire_safety?sslmode=disable")
	t.Setenv(PostGISExpectedSRIDEnv, "4326")

	_, err := Load()
	if err == nil || !strings.Contains(err.Error(), ChatAuthTokenEnv) {
		t.Fatalf("Load() error = %v, want chat/MCP token reuse rejection", err)
	}
}

func TestLoadRejectsInvalidPostGISDSNWithoutLeakingIt(t *testing.T) {
	clearEnvironment(t)
	secret := "do-not-leak-this-password"
	t.Setenv(PostGISEnabledEnv, "true")
	t.Setenv(PostGISDSNEnv, "not-a-url-"+secret)

	_, err := Load()
	if err == nil || !strings.Contains(err.Error(), PostGISDSNEnv) {
		t.Fatalf("Load() error = %v, want error mentioning %s", err, PostGISDSNEnv)
	}
	if strings.Contains(err.Error(), secret) {
		t.Fatal("PostGIS configuration error leaked DSN content")
	}
}

func TestLoadRequiresEnabledSuperAgentSettings(t *testing.T) {
	tests := []struct {
		name       string
		baseURL    string
		apiKey     string
		wantErrKey string
	}{
		{name: "missing base URL", apiKey: "test-open-api-key", wantErrKey: SuperAgentBaseURLEnv},
		{name: "missing key", baseURL: "https://superagent.example.test", wantErrKey: SuperAgentOpenAPIKeyEnv},
		{name: "relative URL", baseURL: "/api", apiKey: "test-open-api-key", wantErrKey: SuperAgentBaseURLEnv},
		{name: "unsupported scheme", baseURL: "ftp://superagent.example.test", apiKey: "test-open-api-key", wantErrKey: SuperAgentBaseURLEnv},
		{name: "URL credentials", baseURL: "https://user:pass@superagent.example.test", apiKey: "test-open-api-key", wantErrKey: SuperAgentBaseURLEnv},
		{name: "URL query", baseURL: "https://superagent.example.test?key=value", apiKey: "test-open-api-key", wantErrKey: SuperAgentBaseURLEnv},
		{name: "invalid key header", baseURL: "https://superagent.example.test", apiKey: "test open api key", wantErrKey: SuperAgentOpenAPIKeyEnv},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			clearEnvironment(t)
			t.Setenv(SuperAgentEnabledEnv, "true")
			t.Setenv(SuperAgentBaseURLEnv, tt.baseURL)
			t.Setenv(SuperAgentOpenAPIKeyEnv, tt.apiKey)

			_, err := Load()
			if err == nil || !strings.Contains(err.Error(), tt.wantErrKey) {
				t.Fatalf("Load() error = %v, want error mentioning %s", err, tt.wantErrKey)
			}
		})
	}
}

func clearEnvironment(t *testing.T) {
	t.Helper()
	for _, key := range []string{
		HTTPAddressEnv,
		SuperAgentEnabledEnv,
		SuperAgentBaseURLEnv,
		SuperAgentOpenAPIKeyEnv,
		SuperAgentConnectTimeoutEnv,
		SuperAgentRecoveryMaxAttemptsEnv,
		SuperAgentRecoveryInitialBackoffEnv,
		SuperAgentMaxMessageBytesEnv,
		SuperAgentProbeSubjectIDEnv,
		SuperAgentProbeTimeoutEnv,
		ChatEnabledEnv,
		ChatPageEnabledEnv,
		ChatAuthTokenEnv,
		ChatAllowLegacyShortTokenEnv,
		ChatSubjectIDEnv,
		ChatAllowedOriginsEnv,
		ChatMaxBodyBytesEnv,
		ChatRunTimeoutEnv,
		ChatSessionTTLEnv,
		ChatMaxSessionsEnv,
		ChatCompatAppIDEnv,
		MCPEnabledEnv,
		MCPAuthTokenEnv,
		MCPScopeModeEnv,
		MCPAllowedTownsEnv,
		MCPMaxBodyBytesEnv,
		MCPToolTimeoutEnv,
		PostGISEnabledEnv,
		PostGISDSNEnv,
		PostGISExpectedSRIDEnv,
		PostGISConnectTimeoutEnv,
		PostGISQueryTimeoutEnv,
		PostGISMaxConnsEnv,
	} {
		t.Setenv(key, "")
	}
}