package cli

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

	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
)

func TestRunNoArgsWritesUsageToStdout(t *testing.T) {
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := Run(nil, &stdout, &stderr)

	if code != 0 {
		t.Fatalf("Run() code = %d, want 0", code)
	}
	if stdout.String() != usage {
		t.Fatalf("stdout = %q, want %q", stdout.String(), usage)
	}
	if stderr.Len() != 0 {
		t.Fatalf("stderr = %q, want empty", stderr.String())
	}
}

func TestRunHelpArgsWriteUsageToStdout(t *testing.T) {
	tests := []struct {
		name string
		args []string
	}{
		{name: "help", args: []string{"help"}},
		{name: "long help flag", args: []string{"--help"}},
		{name: "short help flag", args: []string{"-h"}},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			var stdout bytes.Buffer
			var stderr bytes.Buffer

			code := Run(tt.args, &stdout, &stderr)

			if code != 0 {
				t.Fatalf("Run() code = %d, want 0", code)
			}
			if stdout.String() != usage {
				t.Fatalf("stdout = %q, want %q", stdout.String(), usage)
			}
			if !strings.Contains(stdout.String(), "config validate") || !strings.Contains(stdout.String(), "pipelines list") {
				t.Fatalf("usage does not mention new commands: %q", stdout.String())
			}
			if stderr.Len() != 0 {
				t.Fatalf("stderr = %q, want empty", stderr.String())
			}
		})
	}
}

func TestRunUnknownCommandWritesErrorAndUsageToStderr(t *testing.T) {
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := Run([]string{"extract"}, &stdout, &stderr)

	if code != 2 {
		t.Fatalf("Run() code = %d, want 2", code)
	}
	if stdout.Len() != 0 {
		t.Fatalf("stdout = %q, want empty", stdout.String())
	}
	gotStderr := stderr.String()
	if !strings.Contains(gotStderr, "notarius: unknown command \"extract\"") {
		t.Fatalf("stderr = %q, want unknown command error", gotStderr)
	}
	if !strings.Contains(gotStderr, usage) {
		t.Fatalf("stderr = %q, want usage", gotStderr)
	}
}

func TestRunConfigValidateSuccessWithFakeCatalog(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAML("example", "events", "notes"))
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"config", "validate", "--config", configPath, "--pipeline", "example"}, &stdout, &stderr, Options{
		Catalog: fakeCatalog(t),
	})

	if code != 0 {
		t.Fatalf("RunWithOptions() code = %d, stderr=%q", code, stderr.String())
	}
	if !strings.Contains(stdout.String(), "is valid for pipeline") {
		t.Fatalf("stdout = %q, want validation success", stdout.String())
	}
	if stderr.Len() != 0 {
		t.Fatalf("stderr = %q, want empty", stderr.String())
	}
}

func TestRunConfigValidateReportsParseErrors(t *testing.T) {
	configPath := writeFile(t, "config.yml", "version: 2\n")
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"config", "validate", "--config", configPath}, &stdout, &stderr, Options{})

	if code != 1 {
		t.Fatalf("RunWithOptions() code = %d, want 1", code)
	}
	if stdout.Len() != 0 {
		t.Fatalf("stdout = %q, want empty", stdout.String())
	}
	if !strings.Contains(stderr.String(), "unsupported config version") {
		t.Fatalf("stderr = %q, want parse error", stderr.String())
	}
}

func TestRunConfigValidatePipelineOnlySuccessAndInvalidLane(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAML("example", "events", "notes"))

	t.Run("success", func(t *testing.T) {
		var stdout bytes.Buffer
		var stderr bytes.Buffer

		code := RunWithOptions([]string{"config", "validate", "--config", configPath, "--pipeline", "example", "--only", "notes"}, &stdout, &stderr, Options{
			Catalog: fakeCatalog(t),
		})

		if code != 0 {
			t.Fatalf("RunWithOptions() code = %d, stderr=%q", code, stderr.String())
		}
	})

	t.Run("invalid lane", func(t *testing.T) {
		var stdout bytes.Buffer
		var stderr bytes.Buffer

		code := RunWithOptions([]string{"config", "validate", "--config", configPath, "--pipeline", "example", "--only", "missing"}, &stdout, &stderr, Options{
			Catalog: fakeCatalog(t),
		})

		if code != 1 {
			t.Fatalf("RunWithOptions() code = %d, want 1", code)
		}
		if !strings.Contains(stderr.String(), "selected artifact lane") {
			t.Fatalf("stderr = %q, want invalid lane error", stderr.String())
		}
	})
}

func TestRunConfigValidateOnlyWithoutPipelineFails(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAML("example", "events"))
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"config", "validate", "--config", configPath, "--only", "events"}, &stdout, &stderr, Options{})

	if code != 2 {
		t.Fatalf("RunWithOptions() code = %d, want 2", code)
	}
	if !strings.Contains(stderr.String(), "--only requires --pipeline") {
		t.Fatalf("stderr = %q, want only/pipeline error", stderr.String())
	}
}

func TestRunConfigValidateRejectsMalformedOnlyValues(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAML("example", "events", "notes"))
	tests := []string{",", "notes,", ",notes", "events, ,notes"}

	for _, only := range tests {
		t.Run(only, func(t *testing.T) {
			var stdout bytes.Buffer
			var stderr bytes.Buffer

			code := RunWithOptions([]string{"config", "validate", "--config", configPath, "--pipeline", "example", "--only", only}, &stdout, &stderr, Options{
				Catalog: fakeCatalog(t),
			})

			if code != 2 {
				t.Fatalf("RunWithOptions() code = %d, want 2", code)
			}
			if stdout.Len() != 0 {
				t.Fatalf("stdout = %q, want empty", stdout.String())
			}
			if !strings.Contains(stderr.String(), "--only") {
				t.Fatalf("stderr = %q, want --only error", stderr.String())
			}
		})
	}
}

func TestRunPipelinesListSortedTextOutput(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAMLForPipelines(map[string][]string{
		"zeta":  {"events"},
		"alpha": {"events"},
	}))
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"pipelines", "list", "--config", configPath}, &stdout, &stderr, Options{})

	if code != 0 {
		t.Fatalf("RunWithOptions() code = %d, stderr=%q", code, stderr.String())
	}
	if got, want := stdout.String(), "alpha\nzeta\n"; got != want {
		t.Fatalf("stdout = %q, want %q", got, want)
	}
}

func TestRunPipelinesListStableJSONOutput(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAMLForPipelines(map[string][]string{
		"b": {"events"},
		"a": {"events"},
	}))
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"pipelines", "list", "--config", configPath, "--json"}, &stdout, &stderr, Options{})

	if code != 0 {
		t.Fatalf("RunWithOptions() code = %d, stderr=%q", code, stderr.String())
	}
	if got, want := stdout.String(), "{\"pipelines\":[\"a\",\"b\"]}\n"; got != want {
		t.Fatalf("stdout = %q, want %q", got, want)
	}
}

func TestRunUsesNotariusConfigWhenConfigFlagAbsent(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAML("example", "events"))
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"pipelines", "list"}, &stdout, &stderr, Options{
		LookupEnv: mapLookup(map[string]string{"NOTARIUS_CONFIG": configPath}),
	})

	if code != 0 {
		t.Fatalf("RunWithOptions() code = %d, stderr=%q", code, stderr.String())
	}
	if got, want := stdout.String(), "example\n"; got != want {
		t.Fatalf("stdout = %q, want %q", got, want)
	}
}

func TestRunConfigValidateResolvesAPIKeyEnvThroughOptions(t *testing.T) {
	configPath := writeTestConfig(t, `version: 1
llm_profiles:
  default:
    api_key_env: NOTARIUS_TEST_API_KEY
pipelines:
  example:
    input: fake/input
    artifacts:
      events:
        extract: fake/extract
`)
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"config", "validate", "--config", configPath}, &stdout, &stderr, Options{
		LookupEnv: mapLookup(map[string]string{"NOTARIUS_TEST_API_KEY": "secret"}),
	})

	if code != 0 {
		t.Fatalf("RunWithOptions() code = %d, stderr=%q", code, stderr.String())
	}
}

func TestRunMissingConfigPathProducesActionableError(t *testing.T) {
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"config", "validate", "--config", filepath.Join(t.TempDir(), "missing.yml")}, &stdout, &stderr, Options{})

	if code != 1 {
		t.Fatalf("RunWithOptions() code = %d, want 1", code)
	}
	if !strings.Contains(stderr.String(), "config file") || !strings.Contains(stderr.String(), "not available") {
		t.Fatalf("stderr = %q, want actionable missing config error", stderr.String())
	}
}

func TestRunRejectsAdHocStructuralFlags(t *testing.T) {
	configPath := writeTestConfig(t, testConfigYAML("example", "events"))
	flags := []string{"--extractor", "--chunker", "--input", "--merge", "--normalize"}

	for _, flagName := range flags {
		t.Run(flagName, func(t *testing.T) {
			var stdout bytes.Buffer
			var stderr bytes.Buffer

			code := RunWithOptions([]string{"config", "validate", "--config", configPath, flagName, "value"}, &stdout, &stderr, Options{})

			if code != 2 {
				t.Fatalf("RunWithOptions() code = %d, want 2", code)
			}
			if !strings.Contains(stderr.String(), "flag provided but not defined") {
				t.Fatalf("stderr = %q, want invalid flag error", stderr.String())
			}
		})
	}
}

func TestRunInvalidFlagsExitTwo(t *testing.T) {
	var stdout bytes.Buffer
	var stderr bytes.Buffer

	code := RunWithOptions([]string{"pipelines", "list", "--bogus"}, &stdout, &stderr, Options{})

	if code != 2 {
		t.Fatalf("RunWithOptions() code = %d, want 2", code)
	}
	if !strings.Contains(stderr.String(), "flag provided but not defined") {
		t.Fatalf("stderr = %q, want invalid flag error", stderr.String())
	}
}

func writeTestConfig(t *testing.T, content string) string {
	t.Helper()
	return writeFile(t, "config.yml", content)
}

func writeFile(t *testing.T, name string, content string) string {
	t.Helper()
	path := filepath.Join(t.TempDir(), name)
	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
		t.Fatalf("write %s: %v", name, err)
	}
	return path
}

func testConfigYAML(pipelineID string, laneIDs ...string) string {
	return testConfigYAMLForPipelines(map[string][]string{pipelineID: laneIDs})
}

func testConfigYAMLForPipelines(pipelines map[string][]string) string {
	var b strings.Builder
	b.WriteString("version: 1\n")
	b.WriteString("pipelines:\n")
	for pipelineID, laneIDs := range pipelines {
		b.WriteString("  " + pipelineID + ":\n")
		b.WriteString("    input: fake/input\n")
		b.WriteString("    artifacts:\n")
		for _, laneID := range laneIDs {
			b.WriteString("      " + laneID + ":\n")
			b.WriteString("        extract: fake/extract\n")
		}
	}
	return b.String()
}

func fakeCatalog(t *testing.T) pipeline.ModuleCatalog {
	t.Helper()
	inputs := pipeline.NewInputAdapterRegistry()
	chunkers := pipeline.NewChunkerRegistry()
	extractors := pipeline.NewExtractorRegistry()
	mergers := pipeline.NewMergerRegistry()
	normalizers := pipeline.NewNormalizerRegistry()
	validators := pipeline.NewValidatorRegistry()
	outputs := pipeline.NewOutputEncoderRegistry()

	mustRegisterInput(t, inputs, pipeline.ModuleSpec{Key: "fake/input", Stage: pipeline.StageInput, Provides: []string{"source"}})
	mustRegisterChunker(t, chunkers, pipeline.ModuleSpec{Key: "generic", Stage: pipeline.StageChunk, Requires: []string{"source"}, Provides: []string{"chunks"}})
	mustRegisterExtractor(t, extractors, pipeline.ModuleSpec{Key: "fake/extract", Stage: pipeline.StageExtract, Requires: []string{"chunks"}, Provides: []string{"artifact"}})
	mustRegisterMerger(t, mergers, pipeline.ModuleSpec{Key: "appendorder", Stage: pipeline.StageMerge, Requires: []string{"artifact"}, Provides: []string{"merged"}})
	mustRegisterNormalizer(t, normalizers, pipeline.ModuleSpec{Key: "noop", Stage: pipeline.StageNormalize, Requires: []string{"merged"}, Provides: []string{"normalized"}})
	mustRegisterOutput(t, outputs, pipeline.ModuleSpec{Key: "json", Stage: pipeline.StageOutput, Requires: []string{"normalized"}})

	return pipeline.ModuleCatalog{
		Inputs:      inputs,
		Chunkers:    chunkers,
		Extractors:  extractors,
		Mergers:     mergers,
		Normalizers: normalizers,
		Validators:  validators,
		Outputs:     outputs,
	}
}

func mustRegisterInput(t *testing.T, registry *pipeline.InputAdapterRegistry, spec pipeline.ModuleSpec) {
	t.Helper()
	if err := registry.RegisterWithSpec(spec, func() (contracts.InputAdapter, error) { return nil, nil }); err != nil {
		t.Fatalf("register input: %v", err)
	}
}

func mustRegisterChunker(t *testing.T, registry *pipeline.ChunkerRegistry, spec pipeline.ModuleSpec) {
	t.Helper()
	if err := registry.RegisterWithSpec(spec, func() (contracts.Chunker, error) { return nil, nil }); err != nil {
		t.Fatalf("register chunker: %v", err)
	}
}

func mustRegisterExtractor(t *testing.T, registry *pipeline.ExtractorRegistry, spec pipeline.ModuleSpec) {
	t.Helper()
	if err := registry.RegisterWithSpec(spec, func() (contracts.Extractor, error) { return nil, nil }); err != nil {
		t.Fatalf("register extractor: %v", err)
	}
}

func mustRegisterMerger(t *testing.T, registry *pipeline.MergerRegistry, spec pipeline.ModuleSpec) {
	t.Helper()
	if err := registry.RegisterWithSpec(spec, func() (contracts.Merger, error) { return nil, nil }); err != nil {
		t.Fatalf("register merger: %v", err)
	}
}

func mustRegisterNormalizer(t *testing.T, registry *pipeline.NormalizerRegistry, spec pipeline.ModuleSpec) {
	t.Helper()
	if err := registry.RegisterWithSpec(spec, func() (contracts.Normalizer, error) { return nil, nil }); err != nil {
		t.Fatalf("register normalizer: %v", err)
	}
}

func mustRegisterOutput(t *testing.T, registry *pipeline.OutputEncoderRegistry, spec pipeline.ModuleSpec) {
	t.Helper()
	if err := registry.RegisterWithSpec(spec, func() (contracts.OutputEncoder, error) { return nil, nil }); err != nil {
		t.Fatalf("register output: %v", err)
	}
}

func mapLookup(values map[string]string) func(string) (string, bool) {
	return func(key string) (string, bool) {
		value, ok := values[key]
		return value, ok
	}
}