/*
Copyright © The ESO Authors

Licensed 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

    https://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 vault

import (
	"context"
	"errors"
	"fmt"
	"strings"

	esv1 "github.com/external-secrets/external-secrets/apis/externalsecrets/v1"
	"github.com/external-secrets/external-secrets/runtime/constants"
	"github.com/external-secrets/external-secrets/runtime/find"
	"github.com/external-secrets/external-secrets/runtime/metrics"
)

const (
	errUnsupportedKvVersion = "cannot perform find by tag operations with kv version v1"
)

// GetAllSecrets gets multiple secrets from the provider and loads into a kubernetes secret.
// First load all secrets from secretStore path configuration
// Then, gets secrets from a matching name or matching custom_metadata.
func (c *client) GetAllSecrets(ctx context.Context, ref esv1.ExternalSecretFind) (map[string][]byte, error) {
	if c.store.Version == esv1.VaultKVStoreV1 && ref.Tags != nil {
		return nil, errors.New(errUnsupportedKvVersion)
	}
	searchPath := ""
	if ref.Path != nil {
		searchPath = *ref.Path + "/"
	}
	potentialSecrets, err := c.listSecrets(ctx, searchPath)
	if err != nil {
		return nil, err
	}
	if ref.Name != nil {
		return c.findSecretsFromName(ctx, potentialSecrets, *ref.Name)
	}
	return c.findSecretsFromTags(ctx, potentialSecrets, ref.Tags)
}

func (c *client) findSecretsFromTags(ctx context.Context, candidates []string, tags map[string]string) (map[string][]byte, error) {
	secrets := make(map[string][]byte)
	for _, name := range candidates {
		match := true
		metadata, err := c.readSecretMetadata(ctx, name)
		if err != nil {
			return nil, err
		}
		for tk, tv := range tags {
			p, ok := metadata[tk]
			if !ok || p != tv {
				match = false
				break
			}
		}
		if match {
			secret, err := c.GetSecret(ctx, esv1.ExternalSecretDataRemoteRef{Key: name})
			if errors.Is(err, esv1.NoSecretError{}) {
				continue
			}
			if err != nil {
				return nil, err
			}
			if secret != nil {
				secrets[name] = secret
			}
		}
	}
	return secrets, nil
}

func (c *client) findSecretsFromName(ctx context.Context, candidates []string, ref esv1.FindName) (map[string][]byte, error) {
	secrets := make(map[string][]byte)
	matcher, err := find.New(ref)
	if err != nil {
		return nil, err
	}
	for _, name := range candidates {
		ok := matcher.MatchName(name)
		if ok {
			secret, err := c.GetSecret(ctx, esv1.ExternalSecretDataRemoteRef{Key: name})
			if errors.Is(err, esv1.NoSecretError{}) {
				continue
			}
			if err != nil {
				return nil, err
			}
			if secret != nil {
				secrets[name] = secret
			}
		}
	}
	return secrets, nil
}

func (c *client) listSecrets(ctx context.Context, path string) ([]string, error) {
	secrets := make([]string, 0)
	url, err := c.buildMetadataPath(path)
	if err != nil {
		return nil, err
	}
	secret, err := c.logical.ListWithContext(ctx, url)
	metrics.ObserveAPICall(constants.ProviderHCVault, constants.CallHCVaultListSecrets, err)
	if err != nil {
		return nil, fmt.Errorf(errReadSecret, err)
	}
	if secret == nil {
		return nil, esv1.NoSecretError{}
	}
	t, ok := secret.Data["keys"]
	if !ok {
		return nil, nil
	}
	paths := t.([]any)
	for _, p := range paths {
		strPath := p.(string)
		fullPath := path + strPath // because path always ends with a /
		if path == "" {
			fullPath = strPath
		}
		// Recurrently find secrets
		if !strings.HasSuffix(p.(string), "/") {
			secrets = append(secrets, fullPath)
		} else {
			partial, err := c.listSecrets(ctx, fullPath)
			if err != nil {
				return nil, err
			}
			secrets = append(secrets, partial...)
		}
	}
	return secrets, nil
}