package app

import (
	"context"
	"fmt"

	"gitea.maximumdirect.net/eric/narratio/internal/artifacts"
	"gitea.maximumdirect.net/eric/narratio/internal/config"
	"gitea.maximumdirect.net/eric/narratio/internal/manifest"
)

func validateBoundedPrerequisites(plan BoundedPlan, m *manifest.Manifest) error {
	if !plan.HasExplicitBounds() {
		return nil
	}
	for _, name := range plan.PrefixNames() {
		status := "absent"
		if m != nil && m.Stages != nil && m.Stages[name] != nil {
			stageStatus := m.Stages[name].Status
			if stageStatus == manifest.StatusSucceeded || stageStatus == manifest.StatusSkipped {
				continue
			}
			if stageStatus != "" {
				status = string(stageStatus)
			}
		}
		return fmt.Errorf(
			"prerequisite stage %q has unusable status %q before selected start %q; widen the range with --from %s or recover %s explicitly",
			name,
			status,
			plan.From(),
			name,
			name,
		)
	}
	return nil
}

func inspectBoundedPrerequisites(ctx context.Context, cfg *config.Config, plan BoundedPlan, store manifest.Store) error {
	if !plan.HasExplicitBounds() || len(plan.PrefixNames()) == 0 {
		return nil
	}
	if cfg == nil || cfg.Pipeline == nil || cfg.Session == nil {
		return fmt.Errorf("bounded prerequisite inspection requires resolved pipeline and session configuration")
	}
	if store == nil {
		store = &manifest.LocalStore{}
	}
	path := artifacts.SessionManifestPathForCampaign(
		cfg.Pipeline.Workspace.Root,
		cfg.Session.Campaign,
		cfg.Session.SessionID,
	)
	m, present, err := loadManifestAtPathIfPresent(ctx, store, path)
	if err != nil {
		return err
	}
	if !present {
		m = nil
	}
	return validateBoundedPrerequisites(plan, m)
}