package ckconfig

import (
	"context"
	"errors"
	"io"
	"strings"
	"testing"

	commandkit "gitea.maximumdirect.net/eric/CommandKit"
	configkit "gitea.maximumdirect.net/eric/ConfigKit"
)

func TestComparisonCapabilitiesAreIndependentAndCaptured(t *testing.T) {
	type input struct{ Value string }
	var inputCalls, stateCalls, acquireCalls, compareCalls int
	compare := func(context.Context, ComparisonRequest[input], struct{}) (commandkit.Acquired[[]configkit.Difference], error) {
		compareCalls++
		return commandkit.Acquired[[]configkit.Difference]{}, nil
	}
	operations := []Operation{Diff}
	suite := Suite[input, struct{}]{
		NewInput: func() input { inputCalls++; return input{} },
		NewState: func() struct{} { stateCalls++; return struct{}{} },
		Scopes: []Scope[input, struct{}]{
			{Name: "app", Operations: operations, Compare: compare},
			{Name: "promptkit", Operations: []Operation{Diff, Show, Validate}, Acquire: func(context.Context, Request, input, struct{}) (commandkit.Acquired[View], error) {
				acquireCalls++
				return commandkit.Acquired[View]{}, nil
			}, Compare: compare},
			{Name: "alpha"},
			{Name: "plain", Operations: []Operation{Validate}, Acquire: func(context.Context, Request, input, struct{}) (commandkit.Acquired[View], error) {
				acquireCalls++
				return commandkit.Acquired[View]{}, nil
			}},
		},
	}
	captured := captureSuite(suite)
	declaration := Command(suite)

	// Capability metadata and callback references are copied during capture.
	suite.Scopes[0].Operations[0] = Show
	suite.Scopes[0].Compare = nil

	app := newConfigTestApp(t, declaration)
	var output strings.Builder
	outcome := app.Execute(context.Background(), []string{"config", "scopes"}, commandkit.Streams{Out: &output, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeSuccess {
		t.Fatalf("scope discovery outcome = %#v", outcome)
	}
	if got, want := output.String(), "app: diff\npromptkit: validate, show, diff\nalpha: \nplain: validate\n"; got != want {
		t.Fatalf("scope discovery = %q, want %q", got, want)
	}

	// A family-wide diff command is available, but unsupported scopes fail before
	// suite factories or either provider runs.
	outcome = app.Execute(context.Background(), []string{"config", "diff", "--scope", "plain"}, commandkit.Streams{Out: io.Discard, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeUsage {
		t.Fatalf("unsupported scope outcome = %#v", outcome)
	}
	if inputCalls != 0 || stateCalls != 0 || acquireCalls != 0 || compareCalls != 0 {
		t.Fatalf("discovery or preflight invoked suite work: input=%d state=%d acquire=%d compare=%d", inputCalls, stateCalls, acquireCalls, compareCalls)
	}
	if captured.byName["app"].scope.Compare == nil {
		t.Fatal("captured comparison callback was cleared by a source edit")
	}
	if _, err := captured.byName["app"].scope.Compare(context.Background(), ComparisonRequest[input]{}, struct{}{}); err != nil || compareCalls != 1 {
		t.Fatalf("captured comparison callback result=%v calls=%d", err, compareCalls)
	}

	withoutComparison := newConfigTestApp(t, Command(Suite[input, struct{}]{Scopes: []Scope[input, struct{}]{{
		Name: "plain", Operations: []Operation{Validate},
		Acquire: func(context.Context, Request, input, struct{}) (commandkit.Acquired[View], error) {
			return commandkit.Acquired[View]{}, nil
		},
	}}}))
	outcome = withoutComparison.Execute(context.Background(), []string{"config", "diff"}, commandkit.Streams{Out: io.Discard, Err: io.Discard})
	if outcome.Kind != commandkit.OutcomeUsage {
		t.Fatalf("family without comparison exposed diff: %#v", outcome)
	}
}

func TestComparisonCallbackWiringAndRetainedAdapterIssues(t *testing.T) {
	newApp := func(scope Scope[struct{}, struct{}]) error {
		_, err := commandkit.New(commandkit.Identity{Name: "example"}, Command(Suite[struct{}, struct{}]{Scopes: []Scope[struct{}, struct{}]{scope}}))
		return err
	}

	if err := newApp(Scope[struct{}, struct{}]{Name: "app", Operations: []Operation{Diff}}); err == nil {
		t.Fatalf("missing comparison callback error = %v", err)
	}
	if err := newApp(Scope[struct{}, struct{}]{Name: "app", Operations: []Operation{Validate}}); err == nil {
		t.Fatalf("missing ordinary acquisition callback error = %v", err)
	}

	scope := FromConfigKit[struct{}, struct{}, struct{}]("app", "Application configuration", nil)
	scope.Operations = []Operation{Diff}
	scope.Compare = func(context.Context, ComparisonRequest[struct{}], struct{}) (commandkit.Acquired[[]configkit.Difference], error) {
		return commandkit.Acquired[[]configkit.Difference]{}, nil
	}
	retained := scope.issues[0]
	if err := newApp(scope); err == nil || !errors.Is(err, retained) {
		t.Fatalf("narrowed adapter lost its retained loader issue: %v", err)
	}
}