/*
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements.  See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License.  You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package digest

import (
	// this is needed to generate an SHA1 sum for Jars
	// #nosec G505
	"crypto/sha1"
	"crypto/sha256"
	"encoding/base64"
	"encoding/json"
	"hash"
	"io"
	"path/filepath"
	"sort"
	"strconv"
	"strings"

	v1 "github.com/apache/camel-k/v2/pkg/apis/camel/v1"
	"github.com/apache/camel-k/v2/pkg/util"
	"github.com/apache/camel-k/v2/pkg/util/defaults"

	"fmt"
)

const (
	// IntegrationDigestEnvVar -- .
	IntegrationDigestEnvVar = "CAMEL_K_DIGEST"
)

// ComputeForIntegration a digest of the fields that are relevant for the deployment
// Produces a digest that can be used as docker image tag.
func ComputeForIntegration(integration *v1.Integration, configmapVersions []string, secretVersions []string) (string, error) {
	hash := sha256.New()
	// Integration version is relevant
	if _, err := hash.Write([]byte(integration.Status.Version)); err != nil {
		return "", err
	}

	// Integration operator id is relevant
	if _, err := hash.Write([]byte(v1.GetOperatorIDAnnotation(integration))); err != nil {
		return "", err
	}

	// Integration profile is relevant
	if _, err := hash.Write([]byte(v1.GetIntegrationProfileAnnotation(integration))); err != nil {
		return "", err
	}
	//nolint:staticcheck
	if _, err := hash.Write([]byte(v1.GetIntegrationProfileNamespaceAnnotation(integration))); err != nil {
		return "", err
	}

	// Integration Kit is relevant
	if integration.Spec.IntegrationKit != nil {
		if _, err := fmt.Fprintf(hash, "%s/%s", integration.Spec.IntegrationKit.Namespace, integration.Spec.IntegrationKit.Name); err != nil {
			return "", err
		}
	}
	// Profile is relevant
	if _, err := hash.Write([]byte(integration.Spec.Profile)); err != nil {
		return "", err
	}

	// Integration code
	for _, s := range integration.Spec.Sources {
		if s.Content != "" {
			if _, err := hash.Write([]byte(s.Content)); err != nil {
				return "", err
			}
		}
	}

	// Integration flows
	if len(integration.Spec.Flows) > 0 {
		flows, err := v1.ToYamlDSL(integration.Spec.Flows)
		if err != nil {
			return "", err
		}
		if _, err := hash.Write(flows); err != nil {
			return "", err
		}
	}

	// Integration dependencies
	for _, item := range integration.Spec.Dependencies {
		if _, err := hash.Write([]byte(item)); err != nil {
			return "", err
		}
	}

	// Integration configuration
	for _, item := range integration.Spec.Configuration {
		if _, err := hash.Write([]byte(item.String())); err != nil {
			return "", err
		}
	}

	// Git spec
	if integration.Spec.Git != nil {
		gitSpec := integration.Spec.Git.URL + "/" + integration.Spec.Git.Secret
		switch {
		case integration.Spec.Git.Tag != "":
			gitSpec = gitSpec + "/" + integration.Spec.Git.Tag
		case integration.Spec.Git.Branch != "":
			gitSpec = gitSpec + "/" + integration.Spec.Git.Branch
		case integration.Spec.Git.Commit != "":
			gitSpec = gitSpec + "/" + integration.Spec.Git.Commit
		}
		if _, err := hash.Write([]byte(gitSpec)); err != nil {
			return "", err
		}
	}

	// Integration traits
	// Calculation logic prior to 1.10.0 (the new Traits API schema) is maintained
	// in order to keep consistency in the digest calculated from the same set of
	// Trait configurations for backward compatibility.
	if err := computeForTraits(hash, integration.Spec.Traits); err != nil {
		return "", err
	}

	// Integration traits as annotations
	for _, k := range sortedTraitAnnotationsKeys(integration) {
		v := integration.Annotations[k]
		if _, err := fmt.Fprintf(hash, "%s=%v,", k, v); err != nil {
			return "", err
		}
	}

	// Configmap versions
	for _, cm := range configmapVersions {
		if cm != "" {
			if _, err := hash.Write([]byte(cm)); err != nil {
				return "", err
			}
		}
	}

	// Secret versions
	for _, s := range secretVersions {
		if s != "" {
			if _, err := hash.Write([]byte(s)); err != nil {
				return "", err
			}
		}
	}

	// Add a letter at the beginning and use URL safe encoding
	digest := "v" + base64.RawURLEncoding.EncodeToString(hash.Sum(nil))

	return digest, nil
}

func computeForTraits(hash hash.Hash, traits v1.Traits) error {
	specTraitsMap, err := toMap(traits)
	if err != nil {
		return err
	}
	for _, name := range sortedTraitsMapKeys(specTraitsMap) {
		if err := computeForTrait(hash, name, specTraitsMap[name]); err != nil {
			return err
		}
	}

	return nil
}

func computeForTrait(hash hash.Hash, name string, trait map[string]any) error {
	if _, err := hash.Write([]byte(name + "[")); err != nil {
		return err
	}
	// hash legacy configuration first
	if trait["configuration"] != nil {
		if config, ok := trait["configuration"].(map[string]any); ok {
			if err := computeForTraitProps(hash, config); err != nil {
				return err
			}
		}
		delete(trait, "configuration")
	}
	if err := computeForTraitProps(hash, trait); err != nil {
		return err
	}
	if _, err := hash.Write([]byte("]")); err != nil {
		return err
	}

	return nil
}

func computeForTraitProps(hash hash.Hash, props map[string]any) error {
	for _, prop := range util.SortedMapKeys(props) {
		val := props[prop]
		if _, err := fmt.Fprintf(hash, "%s=%v,", prop, val); err != nil {
			return err
		}
	}

	return nil
}

func toMap(traits v1.Traits) (map[string]map[string]any, error) {
	data, err := json.Marshal(traits)
	if err != nil {
		return nil, err
	}
	traitsMap := make(map[string]map[string]any)
	if err = json.Unmarshal(data, &traitsMap); err != nil {
		return nil, err
	}

	return traitsMap, nil
}

// ComputeForIntegrationKit a digest of the fields that are relevant for the deployment
// Produces a digest that can be used as docker image tag.
func ComputeForIntegrationKit(kit *v1.IntegrationKit) (string, error) {
	hash := sha256.New()
	// Kit version is relevant
	if _, err := hash.Write([]byte(kit.Status.Version)); err != nil {
		return "", err
	}

	if _, err := hash.Write([]byte(kit.Spec.Image)); err != nil {
		return "", err
	}

	for _, item := range kit.Spec.Dependencies {
		if _, err := hash.Write([]byte(item)); err != nil {
			return "", err
		}
	}
	for _, item := range kit.Spec.Configuration {
		if _, err := hash.Write([]byte(item.String())); err != nil {
			return "", err
		}
	}

	// Add a letter at the beginning and use URL safe encoding
	digest := "v" + base64.RawURLEncoding.EncodeToString(hash.Sum(nil))

	return digest, nil
}

// ComputeForSource returns a digest for the specific source.
func ComputeForSource(s v1.SourceSpec) (string, error) {
	hash := sha256.New()
	// Operator version is relevant
	if _, err := hash.Write([]byte(defaults.Version)); err != nil {
		return "", err
	}

	if _, err := hash.Write([]byte(s.Content)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(s.Name)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(s.Type)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(s.Language)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(s.ContentKey)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(s.ContentRef)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(s.Loader)); err != nil {
		return "", err
	}
	if _, err := hash.Write([]byte(strconv.FormatBool(s.Compression))); err != nil {
		return "", err
	}

	// Add a letter at the beginning and use URL safe encoding
	digest := "v" + base64.RawURLEncoding.EncodeToString(hash.Sum(nil))

	return digest, nil
}

func sortedTraitsMapKeys(m map[string]map[string]any) []string {
	res := make([]string, len(m))
	i := 0
	for k := range m {
		res[i] = k
		i++
	}
	sort.Strings(res)

	return res
}

// Deprecated: to be removed in future versions.
func sortedTraitAnnotationsKeys(it *v1.Integration) []string {
	res := make([]string, 0, len(it.Annotations))
	for k := range it.Annotations {
		if strings.HasPrefix(k, v1.TraitAnnotationPrefix) {
			res = append(res, k)
		}
	}
	sort.Strings(res)

	return res
}

func ComputeSHA1(elem ...string) (string, error) {
	file := filepath.Join(elem...)

	// #nosec G401
	h := sha1.New()

	err := util.WithFileReader(file, func(file io.Reader) error {
		if _, err := io.Copy(h, file); err != nil {
			return err
		}

		return nil
	})

	if err != nil {
		return "", err
	}

	return base64.StdEncoding.EncodeToString(h.Sum(nil)), nil
}
