package mill

import (
	"fmt"
	"tangled.org/core/spindle/db"
	millv1 "tangled.org/core/spindle/mill/proto/gen"
	"tangled.org/core/spindle/models"
)

func cacheBindingsToProto(bindings []models.CacheBinding) []*millv1.CacheBinding {
	result := make([]*millv1.CacheBinding, len(bindings))
	for i, binding := range bindings {
		result[i] = &millv1.CacheBinding{
			EntryIndex:       uint32(binding.EntryIndex),
			RestoreId:        binding.RestoreID,
			RestoreKey:       binding.RestoreKey,
			RestoreName:      binding.RestoreName,
			RestoreChecksum:  binding.Checksum,
			RestoreSizeBytes: binding.SizeBytes,
			SaveId:           binding.SaveID,
			SaveKey:          binding.SaveKey,
		}
	}
	return result
}

func cacheCapabilities(repoDid string, bindings []models.CacheBinding) ([]db.MillCacheCapability, error) {
	capabilities := make([]db.MillCacheCapability, 0, len(bindings)*2)
	for _, binding := range bindings {
		for _, capability := range []db.MillCacheCapability{
			{Action: "restore", CacheID: binding.RestoreID, StorageKey: binding.RestoreKey},
			{Action: "save", CacheID: binding.SaveID, StorageKey: binding.SaveKey},
		} {
			if capability.CacheID == "" && capability.StorageKey == "" {
				continue
			}
			if capability.CacheID == "" || capability.StorageKey == "" {
				return nil, fmt.Errorf("%s cache id and key must both be set", capability.Action)
			}
			want, err := models.CacheObjectKey(repoDid, capability.CacheID)
			if err != nil {
				return nil, err
			}
			if capability.StorageKey != want {
				return nil, fmt.Errorf("%s cache key %q does not match object id", capability.Action, capability.StorageKey)
			}
			capabilities = append(capabilities, capability)
		}
	}
	return capabilities, nil
}

func nixCacheToProto(grant *models.NixCacheGrant) *millv1.NixCacheGrant {
	if grant == nil {
		return nil
	}
	return &millv1.NixCacheGrant{
		Cache:          grant.Cache,
		PublicKey:      grant.PublicKey,
		PullToken:      grant.PullToken,
		PushToken:      grant.PushToken,
		MaxUploadBytes: grant.MaxUploadBytes,
	}
}