package main

import (
	"bytes"
	"context"
	"io"
	"strings"
	"testing"

	commandkit "gitea.maximumdirect.net/eric/CommandKit"
	"gitea.maximumdirect.net/eric/CommandKit/integrations/ckconfig"
	"go.yaml.in/yaml/v4"
)

func TestSimpleAppComparesFixturesAndKeepsDefaultCommands(t *testing.T) {
	app, err := newApp()
	if err != nil {
		t.Fatal(err)
	}
	var output bytes.Buffer
	outcome := app.Execute(context.Background(), []string{"config", "diff", "--config", "fixtures/before.yml", "--against-config", "fixtures/after.yml"}, commandkit.Streams{Out: &output, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeSuccess {
		t.Fatalf("fixture comparison outcome = %#v", outcome)
	}
	var report yaml.Node
	if err := yaml.Unmarshal(output.Bytes(), &report); err != nil {
		t.Fatalf("comparison report is not YAML: %q: %v", output.String(), err)
	}
	changes := field(report.Content[0], "changes")
	greeting := field(changes, "greeting")
	if greeting == nil || greeting.Value != "Goodbye" {
		t.Fatalf("fixture comparison report = %q", output.String())
	}

	output.Reset()
	outcome = app.Execute(context.Background(), []string{"config", "diff", "--config", "fixtures/before.yml", "--against-config", "fixtures/before.yml"}, commandkit.Streams{Out: &output, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeSuccess {
		t.Fatalf("equal fixture comparison outcome = %#v", outcome)
	}
	if reportNode, err := decodeReport(output.Bytes()); err != nil || len(field(reportNode, "additions").Content) != 0 || len(field(reportNode, "changes").Content) != 0 || len(field(reportNode, "deletions").Content) != 0 {
		t.Fatalf("equal fixture report = %q, decode error %v", output.String(), err)
	}

	output.Reset()
	outcome = app.Execute(context.Background(), []string{"config", "show"}, commandkit.Streams{Out: &output, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeSuccess || output.String() != "greeting: Hello\nschema:\n  version: 2\n" {
		t.Fatalf("default show outcome/output = %#v / %q", outcome, output.String())
	}

	output.Reset()
	outcome = app.Execute(context.Background(), []string{"greet"}, commandkit.Streams{Out: &output, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeSuccess || len(output.String()) == 0 || output.String()[:5] != "Hello" {
		t.Fatalf("default greeting outcome/output = %#v / %q", outcome, output.String())
	}
}

func TestSimpleLoaderDoesNotReplaceExplicitEmptyConfiguration(t *testing.T) {
	_, err := loadAppConfiguration(context.Background(), ckconfig.Selection{Config: commandkit.Supplied[string]{Set: true}})
	if err == nil {
		t.Fatal("explicit empty configuration fell back to the default source")
	}
}

func TestSimpleConfigurationReportingModes(t *testing.T) {
	for _, test := range []struct {
		name           string
		args           []string
		wantOutput     string
		wantDiagnostic string
		quiet          bool
	}{
		{
			name:       "ordinary output hides provider warning",
			args:       []string{"config", "show", "--config", "fixtures/before.yml"},
			wantOutput: "greeting: Hello\nschema:\n  version: 1\n",
		},
		{
			name:  "quiet suppresses configuration report",
			args:  []string{"config", "show", "--config", "fixtures/before.yml", "--quiet"},
			quiet: true,
		},
		{
			name:           "verbose shows ConfigKit warning",
			args:           []string{"config", "show", "--config", "fixtures/before.yml", "--verbose"},
			wantOutput:     "greeting: Hello\nschema:\n  version: 1\n",
			wantDiagnostic: "schema version 1 is supported",
		},
	} {
		t.Run(test.name, func(t *testing.T) {
			outcome, output, diagnostics := executeSimple(t, test.args...)
			if outcome.Kind != commandkit.OutcomeSuccess || outcome.Cause != nil {
				t.Fatalf("outcome = %#v", outcome)
			}
			if output != test.wantOutput {
				t.Errorf("output = %q, want %q", output, test.wantOutput)
			}
			if test.wantDiagnostic != "" && !strings.Contains(diagnostics, test.wantDiagnostic) {
				t.Errorf("diagnostics = %q, want provider warning %q", diagnostics, test.wantDiagnostic)
			}
			if test.wantDiagnostic == "" && diagnostics != "" {
				t.Errorf("diagnostics = %q, want no warning outside verbose mode", diagnostics)
			}
			if strings.Contains(diagnostics, "ERROR:") {
				t.Errorf("diagnostics %q unexpectedly contain a terminal failure", diagnostics)
			}
			if test.quiet && (outcome.Presentation.Output.State != commandkit.DeliverySuppressed || outcome.Presentation.Diagnostics.State != commandkit.DeliverySuppressed) {
				t.Errorf("quiet presentation = %#v, want report and provider warning suppressed", outcome.Presentation)
			}
		})
	}
}

func TestSimpleCustomCommandUsesSharedReportingFlags(t *testing.T) {
	outcome, output, diagnostics := executeSimple(t, "greet", "--quiet")
	if outcome.Kind != commandkit.OutcomeSuccess || output != "" || diagnostics != "" {
		t.Fatalf("quiet greet outcome/output/diagnostics = %#v / %q / %q", outcome, output, diagnostics)
	}
}

func executeSimple(t *testing.T, args ...string) (commandkit.Outcome, string, string) {
	t.Helper()
	app, err := newApp()
	if err != nil {
		t.Fatal(err)
	}
	var output, diagnostics bytes.Buffer
	outcome := app.Execute(context.Background(), args, commandkit.Streams{Out: &output, Err: &diagnostics})
	return outcome, output.String(), diagnostics.String()
}

func field(mapping *yaml.Node, name string) *yaml.Node {
	if mapping == nil || mapping.Kind != yaml.MappingNode {
		return nil
	}
	for index := 0; index+1 < len(mapping.Content); index += 2 {
		if mapping.Content[index].Value == name {
			return mapping.Content[index+1]
		}
	}
	return nil
}

func decodeReport(data []byte) (*yaml.Node, error) {
	var document yaml.Node
	if err := yaml.Unmarshal(data, &document); err != nil {
		return nil, err
	}
	return document.Content[0], nil
}