package config

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

func TestAnnotatedExamples_HP_CFG_01(t *testing.T) {
	t.Parallel()

	serverData := readFixture(t, "server.toml")
	server, err := DecodeServer(serverData)
	if err != nil {
		t.Fatalf("DecodeServer(example): %v", err)
	}
	if server.Queue.DefaultTTL != 15*time.Minute || server.Storage.TerminalRetention != 30*24*time.Hour {
		t.Fatalf("server defaults mismatch: TTL=%s retention=%s", server.Queue.DefaultTTL, server.Storage.TerminalRetention)
	}
	if server.JSONRPC.NonLoopbackBind {
		t.Fatal("disabled loopback JSON-RPC reported as external")
	}

	clientData := readFixture(t, "client.toml")
	client, err := DecodeClient(clientData, ClientOptions{Platform: PlatformUnix, CheckFilesystem: true})
	if err != nil {
		t.Fatalf("DecodeClient(example): %v", err)
	}
	if got := client.Shells.Advertised["bash"]; got != "/usr/bin/bash" && got != "/bin/bash" {
		t.Fatalf("advertised bash = %q", got)
	}
	if client.Client.MaxRunningCommands != 16 || client.Execution.WindowsTermGrace != 10*time.Second {
		t.Fatalf("client defaults mismatch: %+v", client.Client)
	}

	windowsData := readFixture(t, "client.windows.toml")
	windowsClient, err := DecodeClient(windowsData, ClientOptions{Platform: PlatformWindows})
	if err != nil {
		t.Fatalf("DecodeClient(windows example): %v", err)
	}
	if windowsClient.Client.StateDir != `C:\ProgramData\RVBox\state` {
		t.Fatalf("Windows state dir = %q", windowsClient.Client.StateDir)
	}
	if windowsClient.Observability.LivenessPath != "/livez" || windowsClient.Profiles.Light.CPUPercent != 50 {
		t.Fatal("omitted Windows entries did not receive compiled defaults")
	}
}

func TestClientDefaultsDecodeForWindowsWithoutNativeFilesystem(t *testing.T) {
	t.Parallel()
	client, err := DecodeClient([]byte("[client]\nstate_dir = \"C:\\\\ProgramData\\\\RVBox\\\\state\"\ndaemon_cwd = \"C:\\\\ProgramData\\\\RVBox\\\\work\"\n"), ClientOptions{Platform: PlatformWindows, CheckFilesystem: false})
	if err != nil {
		t.Fatalf("DecodeClient Windows defaults: %v", err)
	}
	if client.Shells.SH != "/bin/sh" || client.Shells.CMD == "" {
		t.Fatalf("Windows defaults have unexpected shell paths: %+v", client.Shells)
	}
}

func TestStrictTOMLRejections_HP_CFG_01(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name string
		data []byte
	}{
		{"unknown key", []byte("[server]\nunknown = true\n")},
		{"duplicate key", []byte("[queue]\nmax_server = 2\nmax_server = 3\n")},
		{"duplicate table", []byte("[queue]\nmax_server = 2\n[queue]\nmax_per_client = 1\n")},
		{"bare duration", []byte("[queue]\ndefault_ttl = 15\n")},
		{"invalid utf8", []byte{0xff, 0xfe}},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			t.Parallel()
			if _, err := DecodeServer(test.data); err == nil {
				t.Fatal("DecodeServer() succeeded")
			}
		})
	}
}

func TestExplicitFlagPrecedence_HP_CFG_01(t *testing.T) {
	t.Parallel()

	server, err := DecodeServerWithOverrides(
		[]byte("[queue]\ndefault_ttl = \"20m\"\nmax_server = 9000\n"),
		map[string]string{"queue.default_ttl": "5m"},
	)
	if err != nil {
		t.Fatalf("DecodeServerWithOverrides(): %v", err)
	}
	if server.Queue.DefaultTTL != 5*time.Minute {
		t.Fatalf("explicit flag TTL = %s", server.Queue.DefaultTTL)
	}
	if server.Queue.MaxServer != 9000 {
		t.Fatalf("omitted flag overwrote TOML max_server: %d", server.Queue.MaxServer)
	}

	client, err := DecodeClientWithOverrides(
		[]byte("[client]\nclient_id = \"from-file\"\nmax_running_commands = 12\n"),
		ClientOptions{Platform: PlatformUnix},
		map[string]string{"client.client_id": "from-flag"},
	)
	if err != nil {
		t.Fatalf("DecodeClientWithOverrides(): %v", err)
	}
	if client.Client.ClientID != "from-flag" || client.Client.MaxRunningCommands != 12 {
		t.Fatalf("client precedence mismatch: %+v", client.Client)
	}

	if _, err := DecodeServerWithOverrides(nil, map[string]string{"unknown": "x"}); err == nil {
		t.Fatal("unknown server override accepted")
	}
	if _, err := DecodeClientWithOverrides(nil, ClientOptions{Platform: PlatformUnix}, map[string]string{"client.max_running_commands": "not-a-number"}); err == nil {
		t.Fatal("invalid client override accepted")
	}
}

func TestServerBoundaryAndCrossFieldValidation_HP_CFG_01(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name string
		toml string
	}{
		{"negative duration", "[queue]\ndefault_ttl = \"-1s\"\n"},
		{"retry inversion", "[queue]\nretry_initial = \"31s\"\n"},
		{"queue inversion", "[queue]\nmax_per_client = 10001\n"},
		{"storage equality", "[storage]\ncommand_output_limit_bytes = 33554432\n"},
		{"closeout does not fit", "[storage]\ncommand_closeout_reserve_bytes = 33554432\n"},
		{"watermark inversion", "[flow]\nraw_output_low_bytes = 67108864\n"},
		{"heartbeat equality", "[protocol]\nheartbeat_idle = \"30s\"\n"},
		{"agent ceiling", "[protocol]\nmax_agent_envelope_bytes = 1048577\n"},
		{"zero nonoptional", "[storage]\naudit_limit_bytes = 0\n"},
		{"relative data path", "[server]\ndata_dir = \"relative\"\n"},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			t.Parallel()
			if _, err := DecodeServer([]byte(test.toml)); err == nil {
				t.Fatal("DecodeServer() succeeded")
			}
		})
	}

	for _, field := range []string{"default_ttl", "terminal_retention", "audit_retention"} {
		var source string
		switch field {
		case "default_ttl":
			source = "[queue]\ndefault_ttl = \"0s\"\n"
		case "terminal_retention":
			source = "[storage]\nterminal_retention = \"0s\"\n"
		default:
			source = "[storage]\naudit_retention = \"0s\"\n"
		}
		if _, err := DecodeServer([]byte(source)); err != nil {
			t.Errorf("documented zero for %s rejected: %v", field, err)
		}
	}
}

func TestJSONRPCExternalBindWarningState_HP_CFG_01(t *testing.T) {
	t.Parallel()

	server, err := DecodeServer([]byte("[json_rpc]\nenabled = true\nlisten = \"0.0.0.0:6900\"\n"))
	if err != nil {
		t.Fatalf("DecodeServer(): %v", err)
	}
	if !server.JSONRPC.NonLoopbackBind {
		t.Fatal("enabled external JSON-RPC did not request warning")
	}
}

func TestClientBoundaryShellAndProfileValidation_HP_CFG_01(t *testing.T) {
	t.Parallel()

	tests := []struct {
		name     string
		toml     string
		platform Platform
	}{
		{"invalid URL", "[client]\nserver_url = \"http://example.test\"\n", PlatformUnix},
		{"invalid client id", "[client]\nclient_id = \"contains space\"\n", PlatformUnix},
		{"relative state", "[client]\nstate_dir = \"state\"\n", PlatformUnix},
		{"missing default shell", "[shells]\nsh = \"\"\n", PlatformUnix},
		{"inactive relative Windows shell", "[shells]\ncmd = \"cmd.exe\"\n", PlatformUnix},
		{"reconnect inversion", "[network]\nreconnect_initial = \"61s\"\n", PlatformUnix},
		{"command watermark inversion", "[flow]\nraw_output_command_low_bytes = 1048576\n", PlatformUnix},
		{"client watermark tier inversion", "[flow]\nraw_output_command_high_bytes = 8388608\n", PlatformUnix},
		{"execution ceiling", "[execution]\nmax_script_bytes = 10485761\n", PlatformUnix},
		{"profile missing control", "[profiles.cpu_medium]\nrequired_controls = [\"memory\"]\n", PlatformUnix},
		{"noncanonical device", "[profiles.disk_medium]\nlinux_io_read_bps = { \"08:0\" = 1 }\n", PlatformUnix},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			t.Parallel()
			if _, err := DecodeClient([]byte(test.toml), ClientOptions{Platform: test.platform}); err == nil {
				t.Fatal("DecodeClient() succeeded")
			}
		})
	}
}

func TestShellResolutionIgnoresRequestPATH_HP_CFG_01(t *testing.T) {
	t.Parallel()

	client, err := DecodeClient(nil, ClientOptions{Platform: PlatformUnix, CheckFilesystem: true})
	if err != nil {
		t.Fatalf("DecodeClient(defaults): %v", err)
	}
	requestEnvironment := map[string]string{"PATH": "/tmp/untrusted"}
	_ = requestEnvironment
	resolved := client.Shells.Advertised["bash"]
	if resolved == "" || strings.HasPrefix(resolved, "/tmp/untrusted") {
		t.Fatalf("request PATH changed resolved shell to %q", resolved)
	}
}

func TestAllowedCWDAndExecutableFilesystemChecks_HP_CFG_01(t *testing.T) {
	t.Parallel()

	tempDir := t.TempDir()
	regular := filepath.Join(tempDir, "not-executable")
	if err := os.WriteFile(regular, []byte("x"), 0o600); err != nil {
		t.Fatal(err)
	}
	source := "[shells]\nsh = " + tomlString(regular) + "\nallowed_cwd_roots = [" + tomlString(regular) + "]\n"
	if _, err := DecodeClient([]byte(source), ClientOptions{Platform: PlatformUnix, CheckFilesystem: true}); err == nil {
		t.Fatal("non-executable shell/file CWD root accepted")
	}
}

func TestProfileCombination_HP_CFG_01(t *testing.T) {
	t.Parallel()

	valid := [][]string{{}, {"light"}, {"cpu_heavy", "mem_medium", "disk_medium"}}
	for _, names := range valid {
		if err := ValidateProfileCombination(names); err != nil {
			t.Errorf("ValidateProfileCombination(%v): %v", names, err)
		}
	}
	invalid := [][]string{{"light", "mem_heavy"}, {"cpu_medium", "cpu_heavy"}, {"mem_medium", "mem_medium"}, {"unknown"}}
	for _, names := range invalid {
		if err := ValidateProfileCombination(names); err == nil {
			t.Errorf("ValidateProfileCombination(%v) succeeded", names)
		}
	}
}

func TestParseDurationOverflowAndZero(t *testing.T) {
	t.Parallel()

	if _, err := parseDuration("test", "999999999999999999999h", false); err == nil {
		t.Fatal("duration overflow accepted")
	}
	if value, err := parseDuration("test", "0s", true); err != nil || value != 0 {
		t.Fatalf("allowed zero = (%s, %v)", value, err)
	}
	if _, err := parseDuration("test", "0s", false); err == nil {
		t.Fatal("forbidden zero accepted")
	}
}

func TestLoadErrors(t *testing.T) {
	t.Parallel()

	if _, err := LoadServer(filepath.Join(t.TempDir(), "missing")); err == nil {
		t.Fatal("LoadServer missing file succeeded")
	}
	if _, err := LoadClient(filepath.Join(t.TempDir(), "missing"), PlatformUnix); err == nil {
		t.Fatal("LoadClient missing file succeeded")
	}
}

func TestErrorValuesAreOrdinaryErrors(t *testing.T) {
	t.Parallel()

	_, err := DecodeServer([]byte("[server]\ndata_dir = \"relative\"\n"))
	if err == nil || errors.Is(err, os.ErrNotExist) {
		t.Fatalf("unexpected validation error: %v", err)
	}
}

func readFixture(t *testing.T, name string) []byte {
	t.Helper()
	data, err := os.ReadFile(filepath.Join("..", "..", "docs", "examples", name))
	if err != nil {
		t.Fatal(err)
	}
	return data
}

func tomlString(value string) string {
	return `"` + strings.ReplaceAll(value, `"`, `\"`) + `"`
}