using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Networking;
using TMPro;
using UnityEngine.UI;

public class GeminiChat : MonoBehaviour
{
    public string apiKey = ""; // あなたのGemini APIキー
    public TextMeshProUGUI outputText;
    public InputField IF1;
    public Text outputmessage;

    private List<Content> conversationHistory = new List<Content>(); // 会話履歴（最大100）

    void Start()
    {
        // 初期化時は空の会話でもOK
    }

    public void procMessage(string message)
    {
        string userInput = IF1.text;
        if (!string.IsNullOrEmpty(userInput))
        {
            AddToHistory("user", userInput); // ユーザー発言を履歴に追加
            StartCoroutine(SendRequestToGemini());
        }
    }

    void AddToHistory(string role, string text)
    {
        // Gemini APIのフォーマットは content[].parts[].text を使用
        Content content = new Content
        {
            role = role,
            parts = new Part[]
            {
                new Part { text = text }
            }
        };

        conversationHistory.Add(content);

        // 最大100件までに制限（roleごとではなく全体で100）
        if (conversationHistory.Count > 100)
        {
            conversationHistory.RemoveAt(0);
        }
    }

    IEnumerator SendRequestToGemini()
    {
        string url = "https://generativelanguage.googleapis.com/v1beta/models/gemini-2.0-pro-exp-02-05:generateContent?key=" + apiKey;

        GeminiRequest requestData = new GeminiRequest
        {
            contents = conversationHistory.ToArray()
        };

        string jsonData = JsonUtility.ToJson(requestData, true);
        byte[] postData = System.Text.Encoding.UTF8.GetBytes(jsonData);

        UnityWebRequest request = new UnityWebRequest(url, "POST");
        request.uploadHandler = new UploadHandlerRaw(postData);
        request.downloadHandler = new DownloadHandlerBuffer();
        request.SetRequestHeader("Content-Type", "application/json");

        yield return request.SendWebRequest();

        if (request.result == UnityWebRequest.Result.Success)
        {
            string result = request.downloadHandler.text;
            GeminiResponse response = JsonUtility.FromJson<GeminiResponse>(result);

            string reply = response.candidates[0].content.parts[0].text;

            Debug.Log("Gemini Response: " + reply);

            if (outputText != null)
                outputText.text = reply;

            outputmessage.text = reply;

            // AIの返答を履歴に追加（role: "model"）
            AddToHistory("model", reply);
        }
        else
        {
            Debug.LogError("Gemini API Error: " + request.error);
            outputmessage.text = request.error;
        }
    }

    // JSON構造（Gemini API仕様）
    [System.Serializable]
    public class GeminiRequest
    {
        public Content[] contents;
    }

    [System.Serializable]
    public class Content
    {
        public string role; // "user" or "model"
        public Part[] parts;
    }

    [System.Serializable]
    public class Part
    {
        public string text;
    }

    [System.Serializable]
    public class GeminiResponse
    {
        public Candidate[] candidates;
    }

    [System.Serializable]
    public class Candidate
    {
        public Content content;
    }
}