use actix_web::{HttpRequest, HttpResponse, Responder, delete, get, post, web};
use opentelemetry::KeyValue;
use opentelemetry::trace::{Span, Status, Tracer};
use serde::{Deserialize, Serialize};

use crate::ai::{InsightGenerator, ModelCapabilities, OllamaClient};
use crate::data::Claims;
use crate::database::{ExifDao, InsightDao};
use crate::libraries;
use crate::otel::{extract_context_from_request, global_tracer};
use crate::state::AppState;
use crate::utils::normalize_path;

#[derive(Debug, Deserialize)]
pub struct GeneratePhotoInsightRequest {
    pub file_path: String,
    #[serde(default)]
    pub model: Option<String>,
    #[serde(default)]
    pub system_prompt: Option<String>,
    #[serde(default)]
    pub num_ctx: Option<i32>,
    #[serde(default)]
    pub temperature: Option<f32>,
    #[serde(default)]
    pub top_p: Option<f32>,
    #[serde(default)]
    pub top_k: Option<i32>,
    #[serde(default)]
    pub min_p: Option<f32>,
}

#[derive(Debug, Deserialize)]
pub struct GetPhotoInsightQuery {
    pub path: String,
    /// Library context for this lookup. Used to pick the right content
    /// hash when the same rel_path exists under multiple roots.
    #[serde(default)]
    pub library: Option<String>,
}

#[derive(Debug, Deserialize)]
pub struct RateInsightRequest {
    pub file_path: String,
    pub approved: bool,
}

#[derive(Debug, Deserialize)]
pub struct ExportTrainingDataQuery {
    #[serde(default)]
    pub approved_only: Option<bool>,
}

#[derive(Debug, Serialize)]
pub struct PhotoInsightResponse {
    pub id: i32,
    pub file_path: String,
    pub title: String,
    pub summary: String,
    pub generated_at: i64,
    pub model_version: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub prompt_eval_count: Option<i32>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub eval_count: Option<i32>,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub approved: Option<bool>,
}

#[derive(Debug, Serialize)]
pub struct AvailableModelsResponse {
    pub primary: ServerModels,
    #[serde(skip_serializing_if = "Option::is_none")]
    pub fallback: Option<ServerModels>,
}

#[derive(Debug, Serialize)]
pub struct ServerModels {
    pub url: String,
    pub models: Vec<ModelCapabilities>,
    pub default_model: String,
}

/// POST /insights/generate - Generate insight for a specific photo
#[post("/insights/generate")]
pub async fn generate_insight_handler(
    http_request: HttpRequest,
    _claims: Claims,
    request: web::Json<GeneratePhotoInsightRequest>,
    insight_generator: web::Data<InsightGenerator>,
) -> impl Responder {
    let parent_context = extract_context_from_request(&http_request);
    let tracer = global_tracer();
    let mut span = tracer.start_with_context("http.insights.generate", &parent_context);

    let normalized_path = normalize_path(&request.file_path);

    span.set_attribute(KeyValue::new("file_path", normalized_path.clone()));
    if let Some(ref model) = request.model {
        span.set_attribute(KeyValue::new("model", model.clone()));
    }
    if let Some(ref prompt) = request.system_prompt {
        span.set_attribute(KeyValue::new("has_custom_prompt", true));
        span.set_attribute(KeyValue::new("prompt_length", prompt.len() as i64));
    }
    if let Some(ctx) = request.num_ctx {
        span.set_attribute(KeyValue::new("num_ctx", ctx as i64));
    }

    log::info!(
        "Manual insight generation triggered for photo: {} with model: {:?}, custom_prompt: {}, num_ctx: {:?}",
        normalized_path,
        request.model,
        request.system_prompt.is_some(),
        request.num_ctx
    );

    // Generate insight with optional custom model, system prompt, and context size
    let result = insight_generator
        .generate_insight_for_photo_with_config(
            &normalized_path,
            request.model.clone(),
            request.system_prompt.clone(),
            request.num_ctx,
            request.temperature,
            request.top_p,
            request.top_k,
            request.min_p,
        )
        .await;

    match result {
        Ok(()) => {
            span.set_status(Status::Ok);
            HttpResponse::Ok().json(serde_json::json!({
                "success": true,
                "message": "Insight generated successfully"
            }))
        }
        Err(e) => {
            log::error!("Failed to generate insight: {:?}", e);
            span.set_status(Status::error(e.to_string()));
            HttpResponse::InternalServerError().json(serde_json::json!({
                "error": format!("Failed to generate insight: {:?}", e)
            }))
        }
    }
}

/// GET /insights?path=/path/to/photo.jpg - Fetch insight for specific photo
#[get("/insights")]
pub async fn get_insight_handler(
    _claims: Claims,
    query: web::Query<GetPhotoInsightQuery>,
    app_state: web::Data<AppState>,
    insight_dao: web::Data<std::sync::Mutex<Box<dyn InsightDao>>>,
    exif_dao: web::Data<std::sync::Mutex<Box<dyn ExifDao>>>,
) -> impl Responder {
    let normalized_path = normalize_path(&query.path);
    log::debug!("Fetching insight for {}", normalized_path);

    let otel_context = opentelemetry::Context::new();

    // Expand to rel_paths sharing content so an insight generated under
    // library 1 still shows when the same photo is viewed from library 2.
    let library = libraries::resolve_library_param(&app_state, query.library.as_deref())
        .ok()
        .flatten()
        .unwrap_or_else(|| app_state.primary_library());
    let sibling_paths = {
        let mut exif = exif_dao.lock().expect("Unable to lock ExifDao");
        exif.get_rel_paths_sharing_content(&otel_context, library.id, &normalized_path)
            .unwrap_or_else(|_| vec![normalized_path.clone()])
    };

    let mut dao = insight_dao.lock().expect("Unable to lock InsightDao");

    match dao.get_insight_for_paths(&otel_context, &sibling_paths) {
        Ok(Some(insight)) => {
            let response = PhotoInsightResponse {
                id: insight.id,
                file_path: insight.file_path,
                title: insight.title,
                summary: insight.summary,
                generated_at: insight.generated_at,
                model_version: insight.model_version,
                prompt_eval_count: None,
                eval_count: None,
                approved: insight.approved,
            };
            HttpResponse::Ok().json(response)
        }
        Ok(None) => HttpResponse::NotFound().json(serde_json::json!({
            "error": "Insight not found"
        })),
        Err(e) => {
            log::error!("Failed to fetch insight ({}): {:?}", &query.path, e);
            HttpResponse::InternalServerError().json(serde_json::json!({
                "error": format!("Failed to fetch insight: {:?}", e)
            }))
        }
    }
}

/// DELETE /insights?path=/path/to/photo.jpg - Remove insight (will regenerate on next request)
#[delete("/insights")]
pub async fn delete_insight_handler(
    _claims: Claims,
    query: web::Query<GetPhotoInsightQuery>,
    insight_dao: web::Data<std::sync::Mutex<Box<dyn InsightDao>>>,
) -> impl Responder {
    let normalized_path = normalize_path(&query.path);
    log::info!("Deleting insight for {}", normalized_path);

    let otel_context = opentelemetry::Context::new();
    let mut dao = insight_dao.lock().expect("Unable to lock InsightDao");

    match dao.delete_insight(&otel_context, &normalized_path) {
        Ok(()) => HttpResponse::Ok().json(serde_json::json!({
            "success": true,
            "message": "Insight deleted successfully"
        })),
        Err(e) => {
            log::error!("Failed to delete insight: {:?}", e);
            HttpResponse::InternalServerError().json(serde_json::json!({
                "error": format!("Failed to delete insight: {:?}", e)
            }))
        }
    }
}

/// GET /insights/all - Get all insights
#[get("/insights/all")]
pub async fn get_all_insights_handler(
    _claims: Claims,
    insight_dao: web::Data<std::sync::Mutex<Box<dyn InsightDao>>>,
) -> impl Responder {
    log::debug!("Fetching all insights");

    let otel_context = opentelemetry::Context::new();
    let mut dao = insight_dao.lock().expect("Unable to lock InsightDao");

    match dao.get_all_insights(&otel_context) {
        Ok(insights) => {
            let responses: Vec<PhotoInsightResponse> = insights
                .into_iter()
                .map(|insight| PhotoInsightResponse {
                    id: insight.id,
                    file_path: insight.file_path,
                    title: insight.title,
                    summary: insight.summary,
                    generated_at: insight.generated_at,
                    model_version: insight.model_version,
                    prompt_eval_count: None,
                    eval_count: None,
                    approved: insight.approved,
                })
                .collect();

            HttpResponse::Ok().json(responses)
        }
        Err(e) => {
            log::error!("Failed to fetch all insights: {:?}", e);
            HttpResponse::InternalServerError().json(serde_json::json!({
                "error": format!("Failed to fetch insights: {:?}", e)
            }))
        }
    }
}

/// POST /insights/generate/agentic - Generate insight using agentic tool-calling loop
#[post("/insights/generate/agentic")]
pub async fn generate_agentic_insight_handler(
    http_request: HttpRequest,
    _claims: Claims,
    request: web::Json<GeneratePhotoInsightRequest>,
    insight_generator: web::Data<InsightGenerator>,
    insight_dao: web::Data<std::sync::Mutex<Box<dyn InsightDao>>>,
) -> impl Responder {
    let parent_context = extract_context_from_request(&http_request);
    let tracer = global_tracer();
    let mut span = tracer.start_with_context("http.insights.generate_agentic", &parent_context);

    let normalized_path = normalize_path(&request.file_path);

    span.set_attribute(KeyValue::new("file_path", normalized_path.clone()));
    if let Some(ref model) = request.model {
        span.set_attribute(KeyValue::new("model", model.clone()));
    }
    if let Some(ref prompt) = request.system_prompt {
        span.set_attribute(KeyValue::new("has_custom_prompt", true));
        span.set_attribute(KeyValue::new("prompt_length", prompt.len() as i64));
    }
    if let Some(ctx) = request.num_ctx {
        span.set_attribute(KeyValue::new("num_ctx", ctx as i64));
    }

    let max_iterations: usize = std::env::var("AGENTIC_MAX_ITERATIONS")
        .ok()
        .and_then(|v| v.parse().ok())
        .unwrap_or(12);

    span.set_attribute(KeyValue::new("max_iterations", max_iterations as i64));

    log::info!(
        "Agentic insight generation triggered for photo: {} with model: {:?}, max_iterations: {}",
        normalized_path,
        request.model,
        max_iterations
    );

    let result = insight_generator
        .generate_agentic_insight_for_photo(
            &normalized_path,
            request.model.clone(),
            request.system_prompt.clone(),
            request.num_ctx,
            request.temperature,
            request.top_p,
            request.top_k,
            request.min_p,
            max_iterations,
        )
        .await;

    match result {
        Ok((prompt_eval_count, eval_count)) => {
            span.set_status(Status::Ok);
            // Fetch the stored insight to return it
            let otel_context = opentelemetry::Context::new();
            let mut dao = insight_dao.lock().expect("Unable to lock InsightDao");
            match dao.get_insight(&otel_context, &normalized_path) {
                Ok(Some(insight)) => {
                    let response = PhotoInsightResponse {
                        id: insight.id,
                        file_path: insight.file_path,
                        title: insight.title,
                        summary: insight.summary,
                        generated_at: insight.generated_at,
                        model_version: insight.model_version,
                        prompt_eval_count,
                        eval_count,
                        approved: insight.approved,
                    };
                    HttpResponse::Ok().json(response)
                }
                Ok(None) => HttpResponse::Ok().json(serde_json::json!({
                    "success": true,
                    "message": "Agentic insight generated successfully"
                })),
                Err(e) => {
                    log::warn!("Insight stored but failed to retrieve: {:?}", e);
                    HttpResponse::Ok().json(serde_json::json!({
                        "success": true,
                        "message": "Agentic insight generated successfully"
                    }))
                }
            }
        }
        Err(e) => {
            let error_msg = format!("{:?}", e);
            log::error!("Failed to generate agentic insight: {}", error_msg);
            span.set_status(Status::error(error_msg.clone()));

            if error_msg.contains("tool calling not supported")
                || error_msg.contains("model not available")
            {
                HttpResponse::BadRequest().json(serde_json::json!({
                    "error": format!("Failed to generate agentic insight: {}", error_msg)
                }))
            } else if error_msg.contains("error parsing tool call") {
                HttpResponse::BadRequest().json(serde_json::json!({
                    "error": "Model is not compatible with Ollama's tool calling protocol. Try a model known to support native tool calling (e.g. llama3.1, llama3.2, qwen2.5, mistral-nemo)."
                }))
            } else {
                HttpResponse::InternalServerError().json(serde_json::json!({
                    "error": format!("Failed to generate agentic insight: {}", error_msg)
                }))
            }
        }
    }
}

/// GET /insights/models - List available models from both servers with capabilities
#[get("/insights/models")]
pub async fn get_available_models_handler(
    _claims: Claims,
    app_state: web::Data<crate::state::AppState>,
) -> impl Responder {
    log::debug!("Fetching available models with capabilities");

    let ollama_client = &app_state.ollama;

    // Fetch models with capabilities from primary server
    let primary_models =
        match OllamaClient::list_models_with_capabilities(&ollama_client.primary_url).await {
            Ok(models) => models,
            Err(e) => {
                log::warn!("Failed to fetch models from primary server: {:?}", e);
                vec![]
            }
        };

    let primary = ServerModels {
        url: ollama_client.primary_url.clone(),
        models: primary_models,
        default_model: ollama_client.primary_model.clone(),
    };

    // Fetch models with capabilities from fallback server if configured
    let fallback = if let Some(fallback_url) = &ollama_client.fallback_url {
        match OllamaClient::list_models_with_capabilities(fallback_url).await {
            Ok(models) => Some(ServerModels {
                url: fallback_url.clone(),
                models,
                default_model: ollama_client
                    .fallback_model
                    .clone()
                    .unwrap_or_else(|| ollama_client.primary_model.clone()),
            }),
            Err(e) => {
                log::warn!("Failed to fetch models from fallback server: {:?}", e);
                None
            }
        }
    } else {
        None
    };

    let response = AvailableModelsResponse { primary, fallback };

    HttpResponse::Ok().json(response)
}

/// POST /insights/rate - Rate an insight (thumbs up/down for training data)
#[post("/insights/rate")]
pub async fn rate_insight_handler(
    _claims: Claims,
    request: web::Json<RateInsightRequest>,
    insight_dao: web::Data<std::sync::Mutex<Box<dyn InsightDao>>>,
) -> impl Responder {
    let normalized_path = normalize_path(&request.file_path);
    log::info!(
        "Rating insight for {}: approved={}",
        normalized_path,
        request.approved
    );

    let otel_context = opentelemetry::Context::new();
    let mut dao = insight_dao.lock().expect("Unable to lock InsightDao");

    match dao.rate_insight(&otel_context, &normalized_path, request.approved) {
        Ok(()) => HttpResponse::Ok().json(serde_json::json!({
            "success": true,
            "message": "Insight rated successfully"
        })),
        Err(e) => {
            log::error!("Failed to rate insight: {:?}", e);
            HttpResponse::InternalServerError().json(serde_json::json!({
                "error": format!("Failed to rate insight: {:?}", e)
            }))
        }
    }
}

/// GET /insights/training-data - Export approved training data as JSONL
#[get("/insights/training-data")]
pub async fn export_training_data_handler(
    _claims: Claims,
    query: web::Query<ExportTrainingDataQuery>,
    insight_dao: web::Data<std::sync::Mutex<Box<dyn InsightDao>>>,
) -> impl Responder {
    let approved_only = query.approved_only.unwrap_or(true);
    log::info!("Exporting training data (approved_only={})", approved_only);

    let otel_context = opentelemetry::Context::new();
    let mut dao = insight_dao.lock().expect("Unable to lock InsightDao");

    let insights = if approved_only {
        dao.get_approved_insights(&otel_context)
    } else {
        dao.get_all_insights(&otel_context)
    };

    match insights {
        Ok(insights) => {
            let mut jsonl = String::new();
            for insight in &insights {
                if let Some(ref messages) = insight.training_messages {
                    let entry = serde_json::json!({
                        "file_path": insight.file_path,
                        "model_version": insight.model_version,
                        "generated_at": insight.generated_at,
                        "title": insight.title,
                        "summary": insight.summary,
                        "messages": serde_json::from_str::<serde_json::Value>(messages)
                            .unwrap_or(serde_json::Value::Null),
                    });
                    jsonl.push_str(&entry.to_string());
                    jsonl.push('\n');
                }
            }

            HttpResponse::Ok()
                .content_type("application/jsonl")
                .insert_header(("Content-Disposition", "attachment; filename=\"training_data.jsonl\""))
                .body(jsonl)
        }
        Err(e) => {
            log::error!("Failed to export training data: {:?}", e);
            HttpResponse::InternalServerError().json(serde_json::json!({
                "error": format!("Failed to export training data: {:?}", e)
            }))
        }
    }
}