/*
 * Copyright 2026 CloudWeGo 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
 *
 *     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 main

import (
	"context"
	"errors"
	"flag"
	"fmt"
	"io"
	"os"
	"strings"

	"github.com/cloudwego/eino-ext/components/model/ark"
	"github.com/cloudwego/eino-ext/components/model/openai"
	"github.com/cloudwego/eino/components/model"
	"github.com/cloudwego/eino/schema"
)

func main() {
	var instruction string
	flag.StringVar(&instruction, "instruction", "You are a helpful assistant.", "")
	flag.Parse()

	query := strings.TrimSpace(strings.Join(flag.Args(), " "))
	if query == "" {
		_, _ = fmt.Fprintln(os.Stderr, "usage: go run ./cmd/ch01 -- \"your question\"")
		os.Exit(2)
	}

	ctx := context.Background()
	cm, err := newChatModel(ctx)
	if err != nil {
		_, _ = fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}

	messages := []*schema.Message{
		schema.SystemMessage(instruction),
		schema.UserMessage(query),
	}

	_, _ = fmt.Fprint(os.Stdout, "[assistant] ")
	stream, err := cm.Stream(ctx, messages)
	if err != nil {
		_, _ = fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}
	defer stream.Close()

	for {
		frame, err := stream.Recv()
		if errors.Is(err, io.EOF) {
			break
		}
		if err != nil {
			_, _ = fmt.Fprintln(os.Stderr, err)
			os.Exit(1)
		}
		if frame != nil {
			_, _ = fmt.Fprint(os.Stdout, frame.Content)
		}
	}
	_, _ = fmt.Fprintln(os.Stdout)
}

func newChatModel(ctx context.Context) (model.ToolCallingChatModel, error) {
	if os.Getenv("MODEL_TYPE") == "ark" {
		return ark.NewChatModel(ctx, &ark.ChatModelConfig{
			APIKey:  os.Getenv("ARK_API_KEY"),
			Model:   os.Getenv("ARK_MODEL"),
			BaseURL: os.Getenv("ARK_BASE_URL"),
		})
	}
	return openai.NewChatModel(ctx, &openai.ChatModelConfig{
		APIKey:  os.Getenv("OPENAI_API_KEY"),
		Model:   os.Getenv("OPENAI_MODEL"),
		BaseURL: os.Getenv("OPENAI_BASE_URL"),
		ByAzure: os.Getenv("OPENAI_BY_AZURE") == "true",
	})
}