package ckprompt

import (
	"context"
	"errors"
	"fmt"

	commandkit "gitea.maximumdirect.net/eric/CommandKit"
	"gitea.maximumdirect.net/eric/CommandKit/integrations/ckconfig"
	promptkit "gitea.maximumdirect.net/eric/promptkit"
)

// SmokeRequest pairs the configuration selection with the seed request for one
// concrete PromptKit smoke-test operation. It is passed to the optional
// builder and the Suite.SmokeTest callback.
type SmokeRequest struct {
	// Selection identifies the configuration sources used to load the engine.
	Selection ckconfig.Selection
	// Request contains the native smoke-test operation and its selected inputs.
	Request promptkit.SmokeTestRequest
}

// WithSmokeTesting attaches PromptKit-backed smoke testing to suite while
// preserving its other capabilities and retained issues. The optional builder
// runs before engine loading and receives the seed request, input, state, and
// invocation context. Its complete returned request is passed to PromptKit;
// without a builder, the seed is forwarded unchanged. Reports and errors from
// PromptKit are both retained. A nil loader is kept as a suite wiring issue and
// does not install a smoke-test callback. The callback also retains engine
// loading diagnostics with the report and error.
func WithSmokeTesting[I, S any](
	suite Suite[I, S],
	load func(context.Context, ckconfig.Selection, I, S) (*promptkit.Engine, error),
	build func(context.Context, SmokeRequest, I, S) (promptkit.SmokeTestRequest, error),
) Suite[I, S] {
	if load == nil {
		issues := append([]error(nil), suite.issues...)
		suite.issues = append(issues, errors.New("PromptKit engine loader is nil"))
		return suite
	}

	suite.SmokeTest = func(ctx context.Context, request SmokeRequest, input I, state S) (commandkit.Acquired[*promptkit.SmokeTestReport], error) {
		if err := promptKitContextError(ctx); err != nil {
			return commandkit.Acquired[*promptkit.SmokeTestReport]{}, fmt.Errorf("PromptKit smoke test before building: %w", err)
		}

		concreteRequest := request.Request
		if build != nil {
			built, err := build(ctx, request, input, state)
			if err != nil {
				return commandkit.Acquired[*promptkit.SmokeTestReport]{}, err
			}
			concreteRequest = built
		}
		if err := promptKitContextError(ctx); err != nil {
			return commandkit.Acquired[*promptkit.SmokeTestReport]{}, fmt.Errorf("PromptKit smoke test after building: %w", err)
		}

		engine, _, diagnostics, err := loadPromptKitEngine(ctx, request.Selection, input, state, "", load)
		if err != nil {
			return commandkit.Acquired[*promptkit.SmokeTestReport]{Diagnostics: diagnostics}, err
		}
		if err := promptKitContextError(ctx); err != nil {
			return commandkit.Acquired[*promptkit.SmokeTestReport]{Diagnostics: diagnostics}, fmt.Errorf("PromptKit smoke test before native operation: %w", err)
		}

		report, err := engine.SmokeTest(ctx, concreteRequest)
		return commandkit.Acquired[*promptkit.SmokeTestReport]{Value: report, Diagnostics: diagnostics}, err
	}
	return suite
}