package releasekit

import (
	"context"
	"fmt"

	internaldelivery "gitea.maximumdirect.net/eric/ReleaseKit/internal/delivery"
	"gitea.maximumdirect.net/eric/ReleaseKit/internal/gitea"
)

// DeliveryState describes the result of one delivery invocation.
type DeliveryState string

const (
	// DeliveryNotAttempted means this invocation made no remote write.
	DeliveryNotAttempted DeliveryState = "not_attempted"
	// DeliveryComplete means the release page and all declared assets match.
	DeliveryComplete DeliveryState = "complete"
	// DeliveryPartial means a page or some assets were delivered, with work pending.
	DeliveryPartial DeliveryState = "partial"
	// DeliveryConflict means existing hosted content differs from the declaration.
	DeliveryConflict DeliveryState = "conflict"
	// DeliveryUnknown means a remote write may have succeeded but could not be resolved.
	DeliveryUnknown DeliveryState = "unknown"
)

// GiteaDestination supplies the hosted repository and explicit access token.
type GiteaDestination struct {
	BaseURL    string
	Owner      string
	Repository string
	Token      string
}

// DeliveryAsset identifies a hosted asset by filename and SHA-256 digest.
type DeliveryAsset struct {
	Filename string
	SHA256   string
}

// DeliveryRequest identifies a local tagged checkout and its explicit Gitea
// destination. Build is nil for page-only delivery.
type DeliveryRequest struct {
	RepositoryDir string
	Product       string
	Version       string
	Destination   GiteaDestination
	Build         *BuildResult
}

// DeliveryResult reports hosted content and the state reached by this
// invocation. A partial result may accompany an error.
type DeliveryResult struct {
	Version         string
	CandidateCommit string
	ReleaseURL      string
	State           DeliveryState
	Matching        []DeliveryAsset
	Uploaded        []DeliveryAsset
	Pending         []DeliveryAsset
	Conflicting     []DeliveryAsset
	Uncertain       []DeliveryAsset
}

// Deliver verifies the selected local tag and hosted source, then creates or
// finds its release page and adds any missing declared build assets.
func Deliver(ctx context.Context, request DeliveryRequest) (DeliveryResult, error) {
	result := DeliveryResult{Version: request.Version, State: DeliveryNotAttempted}
	var build *internaldelivery.BuildIdentity
	var assets []gitea.ExpectedAsset
	if request.Build != nil {
		if len(request.Build.Targets) == 0 {
			if len(request.Build.Artifacts) != 0 {
				return result, fmt.Errorf("page-only build result contains artifacts")
			}
		} else {
			var err error
			assets, err = declaredBuildAssets(*request.Build)
			if err != nil {
				return result, err
			}
			targets := make([]string, 0, len(request.Build.Targets))
			for _, target := range request.Build.Targets {
				targets = append(targets, target.OS+"/"+target.Arch)
			}
			build = &internaldelivery.BuildIdentity{
				RepositoryDir:   request.Build.RepositoryDir,
				CandidateCommit: request.Build.CandidateCommit,
				SourceVerified:  request.Build.SourceVerified,
				Version:         request.Build.Version,
				MainPackage:     request.Build.MainPackage,
				BinaryName:      request.Build.BinaryName,
				Targets:         targets,
			}
		}
	}
	destination := gitea.Destination{
		BaseURL: request.Destination.BaseURL, Owner: request.Destination.Owner,
		Repository: request.Destination.Repository, Token: request.Destination.Token,
	}
	internalResult, err := internaldelivery.Deliver(ctx, internaldelivery.Request{
		RepositoryDir: request.RepositoryDir,
		Product:       request.Product,
		Version:       request.Version,
		Destination:   destination,
		Build:         build,
		Assets:        assets,
	})
	result.CandidateCommit = internalResult.CandidateCommit
	result.ReleaseURL = internalResult.ReleaseURL
	result.State = DeliveryState(internalResult.State)
	result.Matching = deliveryAssets(internalResult.Matching)
	result.Uploaded = deliveryAssets(internalResult.Uploaded)
	result.Pending = deliveryAssets(internalResult.Pending)
	result.Conflicting = deliveryAssets(internalResult.Conflicting)
	result.Uncertain = deliveryAssets(internalResult.Uncertain)
	return result, err
}

func deliveryAssets(assets []gitea.AssetIdentity) []DeliveryAsset {
	result := make([]DeliveryAsset, 0, len(assets))
	for _, asset := range assets {
		result = append(result, DeliveryAsset{Filename: asset.Filename, SHA256: asset.SHA256})
	}
	return result
}