/*
 * Copyright 2023-2024 the original author or 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 org.springframework.ai.model.vertexai.autoconfigure.gemini;

import java.io.IOException;

import com.google.auth.oauth2.GoogleCredentials;
import com.google.cloud.vertexai.VertexAI;
import io.micrometer.observation.ObservationRegistry;

import org.springframework.ai.chat.observation.ChatModelObservationConvention;
import org.springframework.ai.model.SpringAIModelProperties;
import org.springframework.ai.model.SpringAIModels;
import org.springframework.ai.model.tool.DefaultToolExecutionEligibilityPredicate;
import org.springframework.ai.model.tool.ToolCallingManager;
import org.springframework.ai.model.tool.ToolExecutionEligibilityPredicate;
import org.springframework.ai.model.tool.autoconfigure.ToolCallingAutoConfiguration;
import org.springframework.ai.retry.autoconfigure.SpringAiRetryAutoConfiguration;
import org.springframework.ai.vertexai.gemini.VertexAiGeminiChatModel;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.boot.autoconfigure.AutoConfiguration;
import org.springframework.boot.autoconfigure.ImportAutoConfiguration;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.retry.support.RetryTemplate;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;

/**
 * Auto-configuration for Vertex AI Gemini Chat.
 *
 * @author Christian Tzolov
 * @author Soby Chacko
 * @author Mark Pollack
 * @author Ilayaperumal Gopinathan
 * @since 1.0.0
 */
@AutoConfiguration(after = { SpringAiRetryAutoConfiguration.class, ToolCallingAutoConfiguration.class })
@ConditionalOnClass({ VertexAI.class, VertexAiGeminiChatModel.class })
@ConditionalOnProperty(name = SpringAIModelProperties.CHAT_MODEL, havingValue = SpringAIModels.VERTEX_AI,
		matchIfMissing = true)
@EnableConfigurationProperties({ VertexAiGeminiChatProperties.class, VertexAiGeminiConnectionProperties.class })
@ImportAutoConfiguration(classes = { SpringAiRetryAutoConfiguration.class, ToolCallingAutoConfiguration.class })
public class VertexAiGeminiChatAutoConfiguration {

	@Bean
	@ConditionalOnMissingBean
	public VertexAI vertexAi(VertexAiGeminiConnectionProperties connectionProperties) throws IOException {

		Assert.hasText(connectionProperties.getProjectId(), "Vertex AI project-id must be set!");
		Assert.hasText(connectionProperties.getLocation(), "Vertex AI location must be set!");
		Assert.notNull(connectionProperties.getTransport(), "Vertex AI transport must be set!");

		var vertexAIBuilder = new VertexAI.Builder().setProjectId(connectionProperties.getProjectId())
			.setLocation(connectionProperties.getLocation())
			.setTransport(com.google.cloud.vertexai.Transport.valueOf(connectionProperties.getTransport().name()));

		if (StringUtils.hasText(connectionProperties.getApiEndpoint())) {
			vertexAIBuilder.setApiEndpoint(connectionProperties.getApiEndpoint());
		}
		if (!CollectionUtils.isEmpty(connectionProperties.getScopes())) {
			vertexAIBuilder.setScopes(connectionProperties.getScopes());
		}

		if (connectionProperties.getCredentialsUri() != null) {
			GoogleCredentials credentials = GoogleCredentials
				.fromStream(connectionProperties.getCredentialsUri().getInputStream());

			vertexAIBuilder.setCredentials(credentials);
		}
		return vertexAIBuilder.build();
	}

	@Bean
	@ConditionalOnMissingBean
	public VertexAiGeminiChatModel vertexAiGeminiChat(VertexAI vertexAi, VertexAiGeminiChatProperties chatProperties,
			ToolCallingManager toolCallingManager, ApplicationContext context, RetryTemplate retryTemplate,
			ObjectProvider<ObservationRegistry> observationRegistry,
			ObjectProvider<ChatModelObservationConvention> observationConvention,
			ObjectProvider<ToolExecutionEligibilityPredicate> vertexAiGeminiToolExecutionEligibilityPredicate) {

		VertexAiGeminiChatModel chatModel = VertexAiGeminiChatModel.builder()
			.vertexAI(vertexAi)
			.defaultOptions(chatProperties.getOptions())
			.toolCallingManager(toolCallingManager)
			.toolExecutionEligibilityPredicate(vertexAiGeminiToolExecutionEligibilityPredicate
				.getIfUnique(() -> new DefaultToolExecutionEligibilityPredicate()))
			.retryTemplate(retryTemplate)
			.observationRegistry(observationRegistry.getIfUnique(() -> ObservationRegistry.NOOP))
			.build();

		observationConvention.ifAvailable(chatModel::setObservationConvention);

		return chatModel;
	}

}
