mod agent_ux;
mod agents;
mod archive;
mod brain;
mod breadcrumbs;
mod code_index;
mod config;
mod context;
mod conversations;
mod matrix_utils;
mod memory;
mod persistence;
mod grpc;
mod orchestrator;
#[cfg(test)]
mod integration_test;
mod sdk;
mod sync;
mod time_context;
mod tokenizer;
mod tools;

use std::sync::Arc;

use matrix_sdk::Client;
use opensearch::http::transport::TransportBuilder;
use opensearch::OpenSearch;
use ruma::{OwnedDeviceId, OwnedUserId};
use tokio::signal;
use tokio::sync::Mutex;
use tracing::{error, info, warn};
use url::Url;

use agents::registry::AgentRegistry;
use archive::indexer::Indexer;
use archive::schema::create_index_if_not_exists;
use brain::conversation::{ContextMessage, ConversationManager};
use conversations::ConversationRegistry;
use memory::schema::create_index_if_not_exists as create_memory_index;
use brain::evaluator::Evaluator;
use brain::personality::Personality;
use brain::responder::Responder;
use config::Config;
use sync::AppState;
use tools::ToolRegistry;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    // Initialize tracing
    tracing_subscriber::fmt()
        .with_env_filter(
            tracing_subscriber::EnvFilter::try_from_default_env()
                .unwrap_or_else(|_| tracing_subscriber::EnvFilter::new("sol=info")),
        )
        .init();

    // Load config
    let config_path =
        std::env::var("SOL_CONFIG").unwrap_or_else(|_| "/etc/sol/sol.toml".into());
    let config = Config::load(&config_path)?;
    info!("Loaded config from {config_path}");

    // Load system prompt
    let prompt_path = std::env::var("SOL_SYSTEM_PROMPT")
        .unwrap_or_else(|_| "/etc/sol/system_prompt.md".into());
    let system_prompt = std::fs::read_to_string(&prompt_path)?;
    info!("Loaded system prompt from {prompt_path}");

    // Read secrets from environment
    let access_token = std::env::var("SOL_MATRIX_ACCESS_TOKEN")
        .map_err(|_| anyhow::anyhow!("SOL_MATRIX_ACCESS_TOKEN not set"))?;
    let device_id = std::env::var("SOL_MATRIX_DEVICE_ID")
        .map_err(|_| anyhow::anyhow!("SOL_MATRIX_DEVICE_ID not set"))?;
    let mistral_api_key = std::env::var("SOL_MISTRAL_API_KEY")
        .map_err(|_| anyhow::anyhow!("SOL_MISTRAL_API_KEY not set"))?;

    // Optional Gitea admin credentials for user impersonation
    let gitea_admin_username = std::env::var("SOL_GITEA_ADMIN_USERNAME").ok();
    let gitea_admin_password = std::env::var("SOL_GITEA_ADMIN_PASSWORD").ok();

    let config = Arc::new(config);

    // Initialize Matrix client with E2EE and sqlite store
    let homeserver = Url::parse(&config.matrix.homeserver_url)?;

    let matrix_client = Client::builder()
        .homeserver_url(homeserver)
        .sqlite_store(&config.matrix.state_store_path, None)
        .build()
        .await?;

    // Restore session
    let user_id: OwnedUserId = config.matrix.user_id.parse()?;
    let device_id: OwnedDeviceId = device_id.into();

    let session = matrix_sdk::AuthSession::Matrix(matrix_sdk::matrix_auth::MatrixSession {
        meta: matrix_sdk::SessionMeta {
            user_id,
            device_id,
        },
        tokens: matrix_sdk::matrix_auth::MatrixSessionTokens {
            access_token,
            refresh_token: None,
        },
    });

    matrix_client.restore_session(session).await?;
    info!(user = %config.matrix.user_id, "Matrix session restored");

    // Initialize OpenSearch client
    let os_url = Url::parse(&config.opensearch.url)?;
    let os_transport = TransportBuilder::new(
        opensearch::http::transport::SingleNodeConnectionPool::new(os_url),
    )
    .build()?;
    let os_client = OpenSearch::new(os_transport);

    // Ensure indices exist
    create_index_if_not_exists(&os_client, &config.opensearch.index).await?;
    create_memory_index(&os_client, &config.opensearch.memory_index).await?;

    // Initialize Mistral client
    let mistral_client = mistralai_client::v1::client::Client::new(
        Some(mistral_api_key),
        None,
        None,
        None,
    )?;
    let mistral = Arc::new(mistral_client);

    // Initialize tokenizer for accurate token counting
    let _tokenizer = Arc::new(
        tokenizer::SolTokenizer::new(config.mistral.tokenizer_path.as_deref())
            .expect("Failed to initialize tokenizer"),
    );
    info!("Tokenizer initialized");

    // Build components
    let system_prompt_text = system_prompt.clone();
    let personality = Arc::new(Personality::new(system_prompt));
    let conversations = Arc::new(Mutex::new(ConversationManager::new(
        config.behavior.room_context_window,
        config.behavior.dm_context_window,
    )));

    // Backfill conversation context from archive before starting
    if config.behavior.backfill_on_join {
        info!("Backfilling conversation context from archive...");
        if let Err(e) = backfill_conversations(&os_client, &config, &conversations).await {
            error!("Backfill failed (non-fatal): {e}");
        }
    }

    // Initialize persistent state database (needed by token store + agent/conversation registries)
    let (store, state_recovery_failed) = match persistence::Store::open(&config.matrix.db_path) {
        Ok(s) => (Arc::new(s), false),
        Err(e) => {
            error!("Failed to open state database at {}: {e}", config.matrix.db_path);
            error!("Falling back to in-memory state — conversations will not survive restarts");
            (Arc::new(persistence::Store::open_memory().expect("in-memory DB must work")), true)
        }
    };

    // Initialize Vault client for secure token storage
    let vault_client = Arc::new(sdk::vault::VaultClient::new(
        &config.vault.url,
        &config.vault.role,
        &config.vault.mount,
    ));

    // Initialize Gitea client if configured
    let gitea_client: Option<Arc<sdk::gitea::GiteaClient>> =
        if let (Some(gitea_config), Some(admin_user), Some(admin_pass)) =
            (&config.services.gitea, &gitea_admin_username, &gitea_admin_password)
        {
            let token_store = Arc::new(sdk::tokens::TokenStore::new(
                store.clone(),
                vault_client.clone(),
            ));
            info!(url = gitea_config.url.as_str(), "Gitea integration enabled");
            Some(Arc::new(sdk::gitea::GiteaClient::new(
                gitea_config.url.clone(),
                admin_user.clone(),
                admin_pass.clone(),
                token_store,
            )))
        } else {
            info!("Gitea integration disabled (missing config or credentials)");
            None
        };

    // Initialize Kratos client if configured
    let kratos_client: Option<Arc<sdk::kratos::KratosClient>> =
        if let Some(kratos_config) = &config.services.kratos {
            info!(url = kratos_config.admin_url.as_str(), "Kratos integration enabled");
            Some(Arc::new(sdk::kratos::KratosClient::new(
                kratos_config.admin_url.clone(),
            )))
        } else {
            info!("Kratos integration disabled (missing config)");
            None
        };

    let tool_registry = Arc::new(ToolRegistry::new(
        os_client.clone(),
        matrix_client.clone(),
        config.clone(),
        gitea_client,
        kratos_client,
        Some(mistral.clone()),
        Some(store.clone()),
    ));
    let indexer = Arc::new(Indexer::new(os_client.clone(), config.clone()));
    let evaluator = Arc::new(Evaluator::new(config.clone(), system_prompt_text.clone()));
    let responder = Arc::new(Responder::new(
        config.clone(),
        personality,
        tool_registry,
        os_client.clone(),
    ));

    // Start background flush task
    let _flush_handle = indexer.start_flush_task();

    // Initialize agent registry and conversation registry (with SQLite backing)
    let agent_registry = Arc::new(AgentRegistry::new(store.clone()));
    let conversation_registry = Arc::new(ConversationRegistry::new(
        config.mistral.default_model.clone(),
        config.agents.compaction_threshold,
        store.clone(),
    ));

    // Build shared state
    let state = Arc::new(AppState {
        config: config.clone(),
        indexer,
        evaluator,
        responder,
        conversations,
        agent_registry,
        conversation_registry,
        mistral,
        opensearch: os_client,
        last_response: Arc::new(tokio::sync::Mutex::new(std::collections::HashMap::new())),
        responding_in: Arc::new(tokio::sync::Mutex::new(std::collections::HashSet::new())),
        silenced_until: Arc::new(tokio::sync::Mutex::new(std::collections::HashMap::new())),
    });

    // Initialize orchestrator agent if conversations API is enabled
    let mut agent_recreated = false;
    if config.agents.use_conversations_api {
        info!("Conversations API enabled — ensuring orchestrator agent exists");
        let agent_tools = tools::ToolRegistry::agent_tool_definitions(
            config.services.gitea.is_some(),
            config.services.kratos.is_some(),
        );
        let mut active_agents: Vec<(&str, &str)> = vec![];
        if config.services.gitea.is_some() {
            active_agents.push(("sol-devtools", "Git repos, issues, PRs, code (Gitea)"));
        }
        if config.services.kratos.is_some() {
            active_agents.push(("sol-identity", "User accounts, sessions, recovery (Kratos)"));
        }
        match state
            .agent_registry
            .ensure_orchestrator(
                &system_prompt_text,
                &config.agents.orchestrator_model,
                agent_tools,
                &state.mistral,
                &active_agents,
                &config.agents.agent_prefix,
            )
            .await
        {
            Ok((agent_id, recreated)) => {
                info!(agent_id = agent_id.as_str(), recreated, "Orchestrator agent ready");
                state.conversation_registry.set_agent_id(agent_id).await;

                if recreated {
                    // Agent was recreated (system prompt changed) — old conversations
                    // are bound to the stale agent and won't work. Reset everything.
                    state.conversation_registry.reset_all().await;
                    agent_recreated = true;
                }
            }
            Err(e) => {
                error!("Failed to create orchestrator agent: {e}");
                error!("Falling back to model-only conversations (no orchestrator)");
            }
        }
    }

    // Clean up hung research sessions from previous runs
    let hung_sessions = store.load_running_research_sessions();
    if !hung_sessions.is_empty() {
        info!(count = hung_sessions.len(), "Found hung research sessions — marking as failed");
        for (session_id, _room_id, query, _findings) in &hung_sessions {
            warn!(session_id = session_id.as_str(), query = query.as_str(), "Cleaning up hung research session");
            store.fail_research_session(session_id);
        }
    }

    // Backfill reactions from Matrix room timelines
    info!("Backfilling reactions from room timelines...");
    if let Err(e) = backfill_reactions(&matrix_client, &state.indexer).await {
        error!("Reaction backfill failed (non-fatal): {e}");
    }

    // Start gRPC server if configured
    if config.grpc.is_some() {
        let orchestrator_id = state.conversation_registry.get_agent_id().await
            .unwrap_or_default();
        let orch = Arc::new(orchestrator::Orchestrator::new(
            config.clone(),
            state.responder.tools(),
            state.mistral.clone(),
            state.conversation_registry.clone(),
            system_prompt_text.clone(),
        ));
        let grpc_state = std::sync::Arc::new(grpc::GrpcState {
            config: config.clone(),
            tools: state.responder.tools(),
            store: store.clone(),
            mistral: state.mistral.clone(),
            matrix: Some(matrix_client.clone()),
            opensearch: {
                // Rebuild a fresh OpenSearch client (os_client was moved into AppState)
                let os_url = url::Url::parse(&config.opensearch.url).ok();
                os_url.map(|u| {
                    let transport = opensearch::http::transport::TransportBuilder::new(
                        opensearch::http::transport::SingleNodeConnectionPool::new(u),
                    ).build().unwrap();
                    opensearch::OpenSearch::new(transport)
                })
            },
            system_prompt: system_prompt_text.clone(),
            orchestrator_agent_id: orchestrator_id,
            orchestrator: Some(orch),
        });
        tokio::spawn(async move {
            if let Err(e) = grpc::start_server(grpc_state).await {
                error!("gRPC server error: {e}");
            }
        });
    }

    // Start sync loop in background
    let sync_client = matrix_client.clone();
    let sync_state = state.clone();
    let sync_handle = tokio::spawn(async move {
        if let Err(e) = sync::start_sync(sync_client, sync_state).await {
            error!("Sync loop error: {e}");
        }
    });

    // If state recovery failed or agent was recreated, sneeze into all rooms
    if state_recovery_failed || agent_recreated {
        info!("State recovery failed — sneezing into all rooms");
        for room in matrix_client.joined_rooms() {
            let content = ruma::events::room::message::RoomMessageEventContent::text_plain(
                "*sneezes*",
            );
            if let Err(e) = room.send(content).await {
                warn!("Failed to sneeze into {}: {e}", room.room_id());
            }
        }
    }

    info!("Sol is running");

    // Wait for shutdown signal
    signal::ctrl_c().await?;
    info!("Shutdown signal received");

    // Cancel sync
    sync_handle.abort();

    info!("Sol has shut down");
    Ok(())
}

/// Backfill conversation context from the OpenSearch archive.
///
/// Queries the most recent messages per room and seeds the ConversationManager
/// so Sol has context surviving restarts.
async fn backfill_conversations(
    os_client: &OpenSearch,
    config: &Config,
    conversations: &Arc<Mutex<ConversationManager>>,
) -> anyhow::Result<()> {
    use serde_json::json;

    let window = config.behavior.room_context_window.max(config.behavior.dm_context_window);
    let index = &config.opensearch.index;

    // Get all distinct rooms
    let agg_body = json!({
        "size": 0,
        "aggs": {
            "rooms": {
                "terms": { "field": "room_id", "size": 500 }
            }
        }
    });

    let response = os_client
        .search(opensearch::SearchParts::Index(&[index]))
        .body(agg_body)
        .send()
        .await?;

    let body: serde_json::Value = response.json().await?;
    let buckets = body["aggregations"]["rooms"]["buckets"]
        .as_array()
        .cloned()
        .unwrap_or_default();

    let mut total = 0;
    for bucket in &buckets {
        let room_id = bucket["key"].as_str().unwrap_or("");
        if room_id.is_empty() {
            continue;
        }

        // Fetch recent messages for this room
        let query = json!({
            "size": window,
            "sort": [{ "timestamp": "asc" }],
            "query": {
                "bool": {
                    "filter": [
                        { "term": { "room_id": room_id } },
                        { "term": { "redacted": false } }
                    ]
                }
            },
            "_source": ["sender_name", "sender", "content", "timestamp"]
        });

        let resp = os_client
            .search(opensearch::SearchParts::Index(&[index]))
            .body(query)
            .send()
            .await?;

        let data: serde_json::Value = resp.json().await?;
        let hits = data["hits"]["hits"].as_array().cloned().unwrap_or_default();

        if hits.is_empty() {
            continue;
        }

        let mut convs = conversations.lock().await;
        for hit in &hits {
            let src = &hit["_source"];
            let sender = src["sender_name"]
                .as_str()
                .or_else(|| src["sender"].as_str())
                .unwrap_or("unknown");
            let content = src["content"].as_str().unwrap_or("");
            let timestamp = src["timestamp"].as_i64().unwrap_or(0);

            convs.add_message(
                room_id,
                false, // we don't know if it's a DM from the archive, use group window
                ContextMessage {
                    sender: sender.to_string(),
                    content: content.to_string(),
                    timestamp,
                },
            );
            total += 1;
        }
    }

    info!(rooms = buckets.len(), messages = total, "Backfill complete");
    Ok(())
}

/// Backfill reactions from Matrix room timelines into the archive.
///
/// For each joined room, fetches recent timeline events and indexes any
/// m.reaction events that aren't already in the archive.
async fn backfill_reactions(
    client: &Client,
    indexer: &Arc<Indexer>,
) -> anyhow::Result<()> {
    use matrix_sdk::room::MessagesOptions;
    use ruma::events::AnySyncTimelineEvent;
    use ruma::uint;

    let rooms = client.joined_rooms();
    let mut total = 0;

    for room in &rooms {
        let room_id = room.room_id().to_string();

        // Fetch recent messages (backwards from now)
        let mut options = MessagesOptions::backward();
        options.limit = uint!(500);

        let messages = match room.messages(options).await {
            Ok(m) => m,
            Err(e) => {
                error!(room = room_id.as_str(), "Failed to fetch timeline for reaction backfill: {e}");
                continue;
            }
        };

        for event in &messages.chunk {
            let Ok(deserialized) = event.raw().deserialize() else {
                continue;
            };

            if let AnySyncTimelineEvent::MessageLike(
                ruma::events::AnySyncMessageLikeEvent::Reaction(reaction_event),
            ) = deserialized
            {
                let original = match reaction_event {
                    ruma::events::SyncMessageLikeEvent::Original(ref o) => o,
                    _ => continue,
                };

                let target_event_id = original.content.relates_to.event_id.to_string();
                let sender = original.sender.to_string();
                let emoji = &original.content.relates_to.key;
                let timestamp: i64 = original.origin_server_ts.0.into();

                indexer.add_reaction(&target_event_id, &sender, emoji, timestamp).await;
                total += 1;
            }
        }
    }

    info!(reactions = total, rooms = rooms.len(), "Reaction backfill complete");
    Ok(())
}