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; }
        private int activeRequests = 0;
        private const int MAX_CONCURRENT_REQUESTS = 5;

        [SerializeField] private string[] apiKeys = { "YOUR_KEY_1", "YOUR_KEY_2" }; 
        private int currentKeyIndex = 0;

        [SerializeField] private string geminiURL = "https://generativelanguage.googleapis.com/v1beta/models/gemini-1.5-flash:generateContent";
        private float nextRequestTime = 0f;

        private string[] fallbackDialogues = {
            "{ \"text\": \"Nice weather, isn't it?\", \"speedMod\": 0.0, \"suspicionMod\": -5.0, \"aggressionMod\": 0.0, \"braveryMod\": 0.0, \"healthMod\": 0.0 }",
            "{ \"text\": \"Did you hear something? Probably just a rat.\", \"speedMod\": 0.0, \"suspicionMod\": 2.0, \"aggressionMod\": 0.1, \"braveryMod\": -5.0, \"healthMod\": 0.0 }",
            "{ \"text\": \"I'm so tired of this shift.\", \"speedMod\": -0.2, \"suspicionMod\": 0.0, \"aggressionMod\": -0.1, \"braveryMod\": 5.0, \"healthMod\": 0.0 }",
            "{ \"text\": \"You looks strong, I should be careful.\", \"speedMod\": 0.1, \"suspicionMod\": 5.0, \"aggressionMod\": -0.2, \"braveryMod\": 10.0, \"healthMod\": 0.0 }"
        };

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

        private string GetNextKey()
        {
            if (apiKeys == null || apiKeys.Length == 0) return "";
            string key = apiKeys[currentKeyIndex];
            currentKeyIndex = (currentKeyIndex + 1) % apiKeys.Length;
            return key;
        }

        public void GetResponse(string persona, string prompt, Action<string> onComplete)
        {
            if (Time.time < nextRequestTime)
            {
                Debug.LogWarning("[Gemini] API is cooling down. Using fallback.");
                onComplete?.Invoke(fallbackDialogues[UnityEngine.Random.Range(0, fallbackDialogues.Length)]);
                return;
            }

            if (activeRequests >= MAX_CONCURRENT_REQUESTS) 
            {
                onComplete?.Invoke(fallbackDialogues[UnityEngine.Random.Range(0, fallbackDialogues.Length)]);
                return; 
            }
            StartCoroutine(PostRequest(persona, prompt, onComplete));
        }

        private IEnumerator PostRequest(string persona, string prompt, Action<string> onComplete)
        {
            activeRequests++;
            
            string jsonInstruction = " Respond ONLY with a JSON object: { " +
                "'text': 'dialogue content', " +
                "'speedMod': 0.0 (change movement speed), " +
                "'suspicionMod': 0.0 (change suspicion level), " +
                "'aggressionMod': 0.0 (0.1 to 0.5 makes NPC shoot faster, negative makes them slower), " +
                "'braveryMod': 0.0 (positive makes them less likely to panic, negative makes them scared), " +
                "'healthMod': 0.0 (positive heals NPC, negative damages them) " +
                "}. Keep values realistic.";

            string escapedPersona = persona.Replace("\"", "\\\"");
            string escapedPrompt = prompt.Replace("\"", "\\\"");

            var jsonBody = $@"{{
                ""systemInstruction"": {{""parts"": [{{ ""text"": ""{escapedPersona} {jsonInstruction}"" }}]}},
                ""contents"": [{{""parts"": [{{ ""text"": ""{escapedPrompt}"" }}]}}],
                ""generationConfig"": {{
                    ""maxOutputTokens"": 150,
                    ""temperature"": 0.8,
                    ""responseMimeType"": ""application/json""
                }}
            }}";

            var requestURL = $"{geminiURL}?key={GetNextKey()}";

            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)
                {
                    var response = JsonUtility.FromJson<GeminiResponse>(request.downloadHandler.text);
                    if (response?.candidates?.Length > 0 && response.candidates[0].content?.parts?.Length > 0)
                    {
                        onComplete?.Invoke(response.candidates[0].content.parts[0].text);
                    }
                }
                else
                {
                    Debug.LogError($"[Gemini] API Error: {request.error}");
                    if (request.responseCode == 429) 
                    {
                        nextRequestTime = Time.time + 60f;
                    }
                    onComplete?.Invoke(fallbackDialogues[UnityEngine.Random.Range(0, fallbackDialogues.Length)]);
                }
            }

            activeRequests--;
        }
    }
}