// Copyright 2026 Google LLC
//
// 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
//
//	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 cloudloggingadminlistlognames

import (
	"context"
	"fmt"

	"github.com/goccy/go-yaml"
	"github.com/googleapis/genai-toolbox/internal/embeddingmodels"
	"github.com/googleapis/genai-toolbox/internal/sources"
	"github.com/googleapis/genai-toolbox/internal/tools"
	"github.com/googleapis/genai-toolbox/internal/util/parameters"
)

const resourceType string = "cloud-logging-admin-list-log-names"

const defaultLimit int = 200

func init() {
	if !tools.Register(resourceType, newConfig) {
		panic(fmt.Sprintf("tool type %q already registered", resourceType))
	}
}

func newConfig(ctx context.Context, name string, decoder *yaml.Decoder) (tools.ToolConfig, error) {
	actual := Config{Name: name}
	if err := decoder.DecodeContext(ctx, &actual); err != nil {
		return nil, err
	}
	return actual, nil
}

type compatibleSource interface {
	UseClientAuthorization() bool
	ListLogNames(ctx context.Context, limit int, accessToken string) ([]string, error)
}

type Config struct {
	Name         string   `yaml:"name" validate:"required"`
	Type         string   `yaml:"type" validate:"required"`
	Source       string   `yaml:"source" validate:"required"`
	Description  string   `yaml:"description" validate:"required"`
	AuthRequired []string `yaml:"authRequired"`
}

// validate interface
var _ tools.ToolConfig = Config{}

func (cfg Config) ToolConfigType() string {
	return resourceType
}

func (cfg Config) Initialize(srcs map[string]sources.Source) (tools.Tool, error) {
	limitDescription := fmt.Sprintf("Maximum number of log entries to return. Default: %d.", defaultLimit)
	params := parameters.Parameters{
		parameters.NewIntParameterWithRequired("limit", limitDescription, false),
	}

	mcpManifest := tools.GetMcpManifest(cfg.Name, cfg.Description, cfg.AuthRequired, params, nil)

	t := Tool{
		Config:      cfg,
		manifest:    tools.Manifest{Description: cfg.Description, Parameters: params.Manifest(), AuthRequired: cfg.AuthRequired},
		mcpManifest: mcpManifest,
		Parameters:  params,
	}
	return t, nil
}

// validate interface
var _ tools.Tool = Tool{}

type Tool struct {
	Config
	manifest    tools.Manifest
	mcpManifest tools.McpManifest
	Parameters  parameters.Parameters `yaml:"parameters"`
}

func (t Tool) Invoke(ctx context.Context, resourceMgr tools.SourceProvider, params parameters.ParamValues, accessToken tools.AccessToken) (any, error) {
	source, err := tools.GetCompatibleSource[compatibleSource](resourceMgr, t.Source, t.Name, t.Type)
	if err != nil {
		return nil, err
	}

	limit := defaultLimit
	paramsMap := params.AsMap()
	if val, ok := paramsMap["limit"].(int); ok && val > 0 {
		limit = val
	} else if ok && val < 0 {
		return nil, fmt.Errorf("limit must be greater than or equal to 1")
	}

	tokenString := ""
	if source.UseClientAuthorization() {
		tokenString, err = accessToken.ParseBearerToken()
		if err != nil {
			return nil, fmt.Errorf("failed to parse access token: %w", err)
		}
	}

	return source.ListLogNames(ctx, limit, tokenString)
}

func (t Tool) ParseParams(data map[string]any, claimsMap map[string]map[string]any) (parameters.ParamValues, error) {
	return parameters.ParseParams(t.Parameters, data, claimsMap)
}

func (t Tool) EmbedParams(ctx context.Context, paramValues parameters.ParamValues, embeddingModelsMap map[string]embeddingmodels.EmbeddingModel) (parameters.ParamValues, error) {
	return paramValues, nil
}

func (t Tool) Manifest() tools.Manifest {
	return t.manifest
}

func (t Tool) McpManifest() tools.McpManifest {
	return t.mcpManifest
}

func (t Tool) Authorized(verifiedAuthServices []string) bool {
	return tools.IsAuthorized(t.AuthRequired, verifiedAuthServices)
}

func (t Tool) RequiresClientAuthorization(resourceMgr tools.SourceProvider) (bool, error) {
	source, err := tools.GetCompatibleSource[compatibleSource](resourceMgr, t.Source, t.Name, t.Type)
	if err != nil {
		return false, err
	}
	return source.UseClientAuthorization(), nil
}

func (t Tool) ToConfig() tools.ToolConfig {
	return t.Config
}

func (t Tool) GetAuthTokenHeaderName(resourceMgr tools.SourceProvider) (string, error) {
	return "Authorization", nil
}

func (t Tool) GetParameters() parameters.Parameters {
	return t.Parameters
}