package doctor

import (
	"context"
	"errors"
	"io"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/aritmolab/thothii/tools/tht/internal/compose"
	"github.com/aritmolab/thothii/tools/tht/internal/config"
)

// Catches treating an unavailable Docker executable as a successful diagnosis.
func TestRunReportsUnavailableDockerWithoutReturningAnExecutionError(t *testing.T) {
	installation := doctorInstallation(t, "")
	runner := &doctorRunner{dockerUnavailable: true}

	report, err := Run(context.Background(), installation, runner)
	if err != nil {
		t.Fatalf("Run() error = %v, want report", err)
	}
	if report.OK || checkStatus(report, "docker") != "failed" {
		t.Fatalf("Run() report = %#v, want failed Docker check", report)
	}
}

// Catches Docker availability short-circuiting a host file-permission failure.
func TestRunChecksUnsafeFilesEvenWhenDockerIsUnavailable(t *testing.T) {
	installation := doctorInstallation(t, "")
	if err := os.Chmod(installation.EnvFile, 0o644); err != nil {
		t.Fatal(err)
	}

	report, err := Run(context.Background(), installation, &doctorRunner{dockerUnavailable: true})
	if err != nil {
		t.Fatal(err)
	}
	if checkStatus(report, "files") != StatusFailed {
		t.Fatalf("Run() files check = %q, want failed; report = %#v", checkStatus(report, "files"), report)
	}
}

// Catches attempts to run in-container diagnostics when core is not running.
func TestRunSkipsContainerDiagnosticsWhenCoreIsStopped(t *testing.T) {
	installation := doctorInstallation(t, "")
	runner := &doctorRunner{services: stoppedServices}

	report, err := Run(context.Background(), installation, runner)
	if err != nil {
		t.Fatal(err)
	}
	if report.OK || checkStatus(report, "workflow") != "skipped" || checkStatus(report, "pi") != "skipped" {
		t.Fatalf("Run() report = %#v, want stopped-core skips", report)
	}
	if strings.Contains(strings.Join(runner.calls, "\n"), " exec -T core ") {
		t.Fatalf("Run() invoked a container diagnostic while core was stopped: %v", runner.calls)
	}
}

// Catches host-Python diagnostics or omission of workflow/Pi checks once core is healthy.
func TestRunUsesOnlyContainerLocalWorkflowAndPiDiagnosticsWhenCoreRuns(t *testing.T) {
	installation := doctorInstallation(t, "")
	runner := &doctorRunner{services: healthyServices}

	report, err := Run(context.Background(), installation, runner)
	if err != nil {
		t.Fatal(err)
	}
	if !report.OK || checkStatus(report, "workflow") != "passed" || checkStatus(report, "pi") != "passed" {
		t.Fatalf("Run() report = %#v, want successful container diagnostics", report)
	}
	assertChecklist(t, report, []string{"descriptor", "files", "docker", "compose", "configuration", "services", "core-http", "frontend-http", "workspace-registry", "workflow", "pi"})
	calls := strings.Join(runner.calls, "\n")
	if !strings.Contains(calls, "exec -T core tht doctor --json") {
		t.Fatalf("Run() calls = %s, want core-local workflow doctor", calls)
	}
	if strings.Contains(calls, ".venv") || strings.Contains(calls, "python") {
		t.Fatalf("Run() calls = %s, must not require host Python", calls)
	}
}

// Catches a claimed valid registry based only on the rendered volume declaration.
func TestRunFailsAnInvalidContainerLocalRegistryState(t *testing.T) {
	installation := doctorInstallation(t, "")
	runner := &doctorRunner{services: healthyServices, registryInvalid: true}

	report, err := Run(context.Background(), installation, runner)
	if err != nil {
		t.Fatal(err)
	}
	if report.OK || checkStatus(report, "workspace-registry") != StatusFailed {
		t.Fatalf("Run() report = %#v, want failed registry diagnostic", report)
	}
	if !strings.Contains(strings.Join(runner.calls, "\n"), "workspace-registry/state/active.json") {
		t.Fatalf("Run() calls = %v, want an actual registry-state read", runner.calls)
	}
}

// Catches Compose health being treated as proof that the HTTP listeners answer requests.
func TestRunReportsEachHTTPReachabilityProbeFailure(t *testing.T) {
	installation := doctorInstallation(t, "")
	for _, endpoint := range []string{"core", "frontend"} {
		t.Run(endpoint, func(t *testing.T) {
			probe := &probeStub{failures: map[string]error{endpoint: errors.New(endpoint + " unreachable")}}
			report, err := RunWithProbe(context.Background(), installation, &doctorRunner{services: healthyServices}, probe)
			if err != nil {
				t.Fatal(err)
			}
			if report.OK || checkStatus(report, endpoint+"-http") != StatusFailed {
				t.Fatalf("RunWithProbe() report = %#v, want failed %s HTTP check", report, endpoint)
			}
		})
	}
}

// Catches a workflow failure leaking a credential from a declared secret file into a report.
func TestRunRedactsWorkflowDiagnosticFailures(t *testing.T) {
	installation := doctorInstallation(t, "WORKFLOW_TOKEN_FILE=%s\n")
	secretPath := filepath.Join(filepath.Dir(installation.EnvFile), "workflow-token")
	if err := os.WriteFile(secretPath, []byte("workflow-secret-value"), 0o600); err != nil {
		t.Fatal(err)
	}
	contents := "WORKFLOW_TOKEN_FILE=" + secretPath + "\n"
	if err := os.WriteFile(installation.EnvFile, []byte(contents), 0o600); err != nil {
		t.Fatal(err)
	}
	runner := &doctorRunner{services: healthyServices, workflowFailure: "workflow-secret-value"}

	report, err := Run(context.Background(), installation, runner)
	if err != nil {
		t.Fatal(err)
	}
	if report.OK || checkStatus(report, "workflow") != "failed" {
		t.Fatalf("Run() report = %#v, want failed workflow check", report)
	}
	if strings.Contains(reportText(report), "workflow-secret-value") {
		t.Fatalf("Run() report exposed a secret: %#v", report)
	}
}

func doctorInstallation(t *testing.T, _ string) config.Installation {
	t.Helper()
	base, err := filepath.EvalSymlinks(os.TempDir())
	if err != nil {
		t.Fatal(err)
	}
	root, err := os.MkdirTemp(base, "tht-doctor-")
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { _ = os.RemoveAll(root) })
	project := filepath.Join(root, "project")
	for _, path := range []string{project, filepath.Join(project, "deploy"), filepath.Join(project, "docker")} {
		if err := os.MkdirAll(path, 0o755); err != nil {
			t.Fatal(err)
		}
	}
	for _, path := range []string{filepath.Join(project, "compose.yaml"), filepath.Join(project, "deploy", "compose.local.yaml"), filepath.Join(project, "docker", "core.Dockerfile")} {
		if err := os.WriteFile(path, []byte("services: {}\n"), 0o600); err != nil {
			t.Fatal(err)
		}
	}
	envFile := filepath.Join(root, "operator.env")
	if err := os.WriteFile(envFile, []byte("SAFE_VALUE=1\n"), 0o600); err != nil {
		t.Fatal(err)
	}
	return config.Installation{Path: filepath.Join(root, "thothii-installation.yaml"), Profile: "local", ProjectDirectory: project, EnvFile: envFile}
}

type doctorRunner struct {
	calls             []string
	dockerUnavailable bool
	services          string
	workflowFailure   string
	registryInvalid   bool
}

func (r *doctorRunner) Run(_ context.Context, args []string, _ io.Reader) (compose.Result, error) {
	call := strings.Join(args, " ")
	r.calls = append(r.calls, call)
	if r.dockerUnavailable {
		return compose.Result{ExitCode: 127}, errors.New("docker unavailable")
	}
	switch {
	case strings.Contains(call, "version --format {{.Client.Version}}"):
		return compose.Result{Stdout: "26.0.0\n"}, nil
	case strings.Contains(call, "compose version --short"):
		return compose.Result{Stdout: "v2.30.0\n"}, nil
	case strings.Contains(call, "config --quiet"):
		return compose.Result{}, nil
	case strings.Contains(call, "config --format json"):
		return compose.Result{Stdout: renderedConfig}, nil
	case strings.Contains(call, "ps --all --format json"):
		if r.services == "" {
			return compose.Result{Stdout: healthyServices}, nil
		}
		return compose.Result{Stdout: r.services}, nil
	case strings.Contains(call, "tht doctor --json"):
		if r.workflowFailure != "" {
			return compose.Result{Stderr: r.workflowFailure, ExitCode: 23}, errors.New("workflow failed")
		}
		return compose.Result{Stdout: `{"ok":true,"checks":[]}`}, nil
	case strings.Contains(call, "workspace-registry/state/active.json"):
		if r.registryInvalid {
			return compose.Result{ExitCode: 23, Stderr: "invalid workspace registry"}, errors.New("registry invalid")
		}
		return compose.Result{Stdout: "registry is valid\n"}, nil
	case strings.Contains(call, "pi --version") || strings.Contains(call, "PI_VERSION") || strings.Contains(call, "io.thothii.pi.version"):
		return compose.Result{Stdout: "0.80.3\n"}, nil
	case strings.Contains(call, "test -w /home/thoth/.pi") || strings.Contains(call, "test -r /home/thoth/.pi/agent/auth.json") || strings.Contains(call, "/health"):
		return compose.Result{Stdout: `{"ready":true}`}, nil
	case strings.Contains(call, "/pi-management/test"):
		return compose.Result{Stdout: `{"ready":true}`}, nil
	case strings.Contains(call, "ps -q core"):
		return compose.Result{Stdout: "core-id\n"}, nil
	}
	return compose.Result{}, nil
}

type probeStub struct{ failures map[string]error }

func (p *probeStub) Probe(_ context.Context, endpoint HTTPProbeTarget) error {
	return p.failures[endpoint.Name]
}

func checkStatus(report Report, name string) string {
	for _, check := range report.Checks {
		if check.Name == name {
			return check.Status
		}
	}
	return ""
}

func reportText(report Report) string {
	parts := make([]string, 0, len(report.Checks))
	for _, check := range report.Checks {
		parts = append(parts, check.Name+" "+check.Status+" "+check.Detail)
	}
	return strings.Join(parts, "\n")
}

func assertChecklist(t *testing.T, report Report, want []string) {
	t.Helper()
	got := make([]string, 0, len(report.Checks))
	for _, check := range report.Checks {
		got = append(got, check.Name)
	}
	if strings.Join(got, ",") != strings.Join(want, ",") {
		t.Fatalf("doctor checklist = %v, want %v", got, want)
	}
}

const renderedConfig = `{"volumes":{"settings":{},"pi-state":{},"workspace-registry":{},"workspace-secrets":{},"sessions":{},"qdrant-data":{},"embedding-models":{}},"services":{"core":{"image":"thothii-core:local","environment":{"THT_LLM_URL":"https://llm.example.invalid"}}}}`

const healthyServices = `[
  {"Service":"core","State":"running","Health":"healthy"},
  {"Service":"frontend","State":"running","Health":"healthy"},
  {"Service":"qdrant","State":"running","Health":"healthy"},
  {"Service":"embedding","State":"running","Health":"healthy"},
  {"Service":"embedding-model-init","State":"exited","ExitCode":0}
]`

const stoppedServices = `[
  {"Service":"core","State":"exited","Health":""},
  {"Service":"frontend","State":"running","Health":"healthy"}
]`