using System.Net;
using System.Text.Json;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;
using Google.GenAI;
using System.Text.Json.Serialization;

namespace CognitiveClarity.api
{
    public class ScenarioRequest
    {
        [JsonPropertyName("prompt")]
        public string Prompt { get; set; } = string.Empty;

        [JsonPropertyName("selectedConcepts")]
        public List<string> SelectedConcepts { get; set; } = new();

        [JsonPropertyName("difficulty")]
        public string Difficulty { get; set; } = "Intermediate";
    }

    public class ScenarioFunction
    {
        private readonly ILogger _logger;

        public ScenarioFunction(ILoggerFactory loggerFactory)
        {
            _logger = loggerFactory.CreateLogger<ScenarioFunction>();
        }

        [Function("GenerateScenario")]
        public async Task<HttpResponseData> Run(
            [HttpTrigger(AuthorizationLevel.Anonymous, "post", Route = "scenario/generate")] HttpRequestData req)
        {
            _logger.LogInformation("C# HTTP trigger function processed a scenario generation request.");

            var requestBody = await new StreamReader(req.Body).ReadToEndAsync();
            var data = JsonSerializer.Deserialize<ScenarioRequest>(requestBody);

            if (data == null || (string.IsNullOrWhiteSpace(data.Prompt) && data.SelectedConcepts.Count == 0))
            {
                var badResponse = req.CreateResponse(HttpStatusCode.BadRequest);
                await badResponse.WriteStringAsync("Please pass a prompt or concepts in the request body");
                return badResponse;
            }

            var apiKey = Environment.GetEnvironmentVariable("GEMINI_API_KEY");
            if (string.IsNullOrEmpty(apiKey))
            {
                _logger.LogError("GEMINI_API_KEY is missing from environment variables.");
                return req.CreateResponse(HttpStatusCode.InternalServerError);
            }

            // Initialize the Gemini Client
            var ai = new GeminiClient(apiKey: apiKey);

            var selectedContext = data.SelectedConcepts.Count > 0 
                ? $"Focus specifically on these CBT concepts: {string.Join(", ", data.SelectedConcepts)}."
                : "";

            var systemInstruction = $@"
            [CONTEXT]
            You are a Clinical CBT Scenario Architect. 
            The user requires a structured clinical simulation designed to address specific cognitive distortions and behavioral challenges.
            Clinical Focus: {selectedContext}
            
            [TASK]
            Transform the user's prompt into a cohesive, structured clinical scenario that sets up a targeted roleplay environment.
            
            [CONSTRAINTS]
            - CATEGORIZATION: You MUST categorize the scenario appropriately (Social Anxiety, Workplace, Relationships, or Self-Talk).
            - DIFFICULTY CALIBRATION: The requested difficulty is '{data.Difficulty}'.
              - 'Beginner': Low stakes, high support, clear-cut distortions, AI character is cooperative.
              - 'Intermediate': Ambiguous stakes, moderate social friction, subtle distortions, AI character has specific needs.
              - 'Advanced': High emotional triggers, persistent clinical resistance, complex cognitive patterns.
            - INTERNAL LOGIC: Provide a detailed ""INTERNAL CBT LOGIC"" section instructing the AI character how to react to the user's progress or cognitive lapses during the future roleplay.
            - CHARACTER VOICE: Define a realistic, emotionally consistent voice profile.
            
            [OUTPUT REQUIREMENTS]
            Return ONLY a valid JSON object conforming exactly to the requested schema. Ensure all arrays and nested objects are populated correctly.
            ";

            var schema = new Schema
            {
                Type = TypeEnum.Object,
                Properties = new Dictionary<string, Schema>
                {
                    { "id", new Schema { Type = TypeEnum.String } },
                    { "title", new Schema { Type = TypeEnum.String } },
                    { "characterName", new Schema { Type = TypeEnum.String } },
                    { "description", new Schema { Type = TypeEnum.String } },
                    { "category", new Schema { Type = TypeEnum.String, Enum = new List<string> { "Social Anxiety", "Workplace", "Relationships", "Self-Talk" } } },
                    { "difficulty", new Schema { Type = TypeEnum.String, Enum = new List<string> { "Beginner", "Intermediate", "Advanced" } } },
                    { "systemInstruction", new Schema { Type = TypeEnum.String } },
                    { "initialMessage", new Schema { Type = TypeEnum.String } },
                    { "cbtFocus", new Schema { Type = TypeEnum.Array, Items = new Schema { Type = TypeEnum.String } } }
                },
                Required = new List<string> { "id", "title", "characterName", "description", "category", "difficulty", "systemInstruction", "initialMessage", "cbtFocus" }
            };

            var promptText = $"Generate a clinical scenario for: {(string.IsNullOrWhiteSpace(data.Prompt) ? "A scenario exploring the chosen CBT concepts." : data.Prompt)}";

            try 
            {
                var response = await ai.Models.GenerateContentAsync(
                    model: "gemini-3.0-flash", 
                    contents: promptText,
                    new GenerateContentConfig 
                    {
                        SystemInstruction = new Content { Parts = new List<Part> { new Part { Text = systemInstruction } } },
                        ResponseMimeType = "application/json",
                        ResponseSchema = schema
                    });

                var successResponse = req.CreateResponse(HttpStatusCode.OK);
                successResponse.Headers.Add("Content-Type", "application/json");
                await successResponse.WriteStringAsync(response.Text!);
                return successResponse;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Failed to generate scenario via Gemini API.");
                var errorResponse = req.CreateResponse(HttpStatusCode.InternalServerError);
                await errorResponse.WriteStringAsync("Error communicating with Gemini API.");
                return errorResponse;
            }
        }
    }
}