using System;
using System.Collections;
using System.Text;
using UnityEngine;
using UnityEngine.Networking;

namespace Hallucinate.AI
{
    [Serializable]
    public class Part { public string text; }

    [Serializable]
    public class Content { public Part[] parts; }

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

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

    public class GeminiService : MonoBehaviour
    {
        public static GeminiService Instance { get; private set; }

        [SerializeField] private string apiKey = "AQ.Ab8RN6I2hU_p8yHiPNNHtWzYBiLugbPP22gC6lzTWaYEWj4v0g"; // Replace with your key
        [SerializeField] private string geminiURL = "https://generativelanguage.googleapis.com/v1beta/models/gemini-flash-latest:generateContent";

        private void Awake()
        {
            if (Instance == null) { Instance = this; DontDestroyOnLoad(gameObject); }
            else { Destroy(gameObject); }
        }

        public void GetResponse(string persona, string prompt, Action<string> onComplete)
        {
            StartCoroutine(PostRequest(persona, prompt, onComplete));
        }

        private IEnumerator PostRequest(string persona, string prompt, Action<string> onComplete)
        {
            var jsonBody = $@"{{
                ""systemInstruction"": {{""parts"": [{{ ""text"": ""{persona}"" }}]}},
                ""contents"": [{{""parts"": [{{ ""text"": ""{prompt}"" }}]}}],
                ""generationConfig"": {{
                    ""maxOutputTokens"": 60,
                    ""temperature"": 0.7
                }}
            }}";

            var requestURL = $"{geminiURL}?key={apiKey}";


            using (var request = new UnityWebRequest(requestURL, "POST"))
            {
                byte[] bodyRaw = Encoding.UTF8.GetBytes(jsonBody);
                request.uploadHandler = new UploadHandlerRaw(bodyRaw);
                request.downloadHandler = new DownloadHandlerBuffer();
                request.SetRequestHeader("Content-Type", "application/json");

                yield return request.SendWebRequest();

                if (request.result == UnityWebRequest.Result.Success)
                {
                    string rawResponse = request.downloadHandler.text;
                    try
                    {
                        var response = JsonUtility.FromJson<GeminiResponse>(rawResponse);
                        if (response != null && 
                            response.candidates != null && 
                            response.candidates.Length > 0 && 
                            response.candidates[0].content != null && 
                            response.candidates[0].content.parts != null && 
                            response.candidates[0].content.parts.Length > 0)
                        {
                            onComplete?.Invoke(response.candidates[0].content.parts[0].text);
                        }
                        else
                        {
                            Debug.LogWarning($"[Gemini] Response structure invalid or blocked. Raw: {rawResponse}");
                        }
                    }
                    catch (Exception e) 
                    { 
                        Debug.LogError($"[Gemini] JSON Parse Error: {e.Message}\nRaw Response: {rawResponse}"); 
                    }
                }
                else
                {
                    Debug.LogError($"[Gemini] API Error: {request.error}");
                }
            }
        }
    }
}