use crate::config::{Config, McpResourceConfig, McpServerConfig};
use crate::consent::{ConsentManager, ConsentScope};
use crate::conversation::ConversationManager;
use crate::credentials::CredentialManager;
use crate::encryption::{self, VaultHandle};
use crate::formatting::MessageFormatter;
use crate::input::InputBuffer;
use crate::mcp::McpToolCall;
use crate::mcp::client::McpClient;
use crate::mcp::factory::McpClientFactory;
use crate::mcp::permission::PermissionLayer;
use crate::mcp::remote_client::{McpRuntimeSecrets, RemoteMcpClient};
use crate::mode::Mode;
use crate::model::{DetailedModelInfo, ModelManager};
use crate::oauth::{DeviceAuthorization, DevicePollState, OAuthClient};
use crate::providers::OllamaProvider;
use crate::storage::{SessionMeta, StorageManager};
use crate::types::{
    ChatParameters, ChatRequest, ChatResponse, Conversation, Message, ModelInfo, ToolCall,
};
use crate::ui::{RoleLabelDisplay, UiController};
use crate::validation::{SchemaValidator, get_builtin_schemas};
use crate::{ChatStream, Provider};
use crate::{
    CodeExecTool, ResourcesDeleteTool, ResourcesGetTool, ResourcesListTool, ResourcesWriteTool,
    ToolRegistry, WebScrapeTool, WebSearchDetailedTool, WebSearchTool,
};
use crate::{Error, Result};
use chrono::Utc;
use log::warn;
use serde_json::{Value, json};
use std::collections::HashMap;
use std::env;
use std::path::PathBuf;
use std::sync::{Arc, Mutex};
use tokio::sync::Mutex as TokioMutex;
use tokio::sync::mpsc::UnboundedSender;
use uuid::Uuid;

pub enum SessionOutcome {
    Complete(ChatResponse),
    Streaming {
        response_id: Uuid,
        stream: ChatStream,
    },
}

#[derive(Debug, Clone)]
pub enum ControllerEvent {
    ToolRequested {
        request_id: Uuid,
        message_id: Uuid,
        tool_name: String,
        data_types: Vec<String>,
        endpoints: Vec<String>,
        tool_calls: Vec<ToolCall>,
    },
}

#[derive(Clone, Debug)]
struct PendingToolRequest {
    message_id: Uuid,
    tool_name: String,
    data_types: Vec<String>,
    endpoints: Vec<String>,
    tool_calls: Vec<ToolCall>,
}

#[derive(Debug, Clone)]
pub struct ToolConsentResolution {
    pub request_id: Uuid,
    pub message_id: Uuid,
    pub tool_name: String,
    pub scope: ConsentScope,
    pub tool_calls: Vec<ToolCall>,
}

fn extract_resource_content(value: &Value) -> Option<String> {
    match value {
        Value::Null => Some(String::new()),
        Value::Bool(flag) => Some(flag.to_string()),
        Value::Number(num) => Some(num.to_string()),
        Value::String(text) => Some(text.clone()),
        Value::Array(items) => {
            let mut segments = Vec::new();
            for item in items {
                if let Some(segment) =
                    extract_resource_content(item).filter(|segment| !segment.is_empty())
                {
                    segments.push(segment);
                }
            }
            if segments.is_empty() {
                None
            } else {
                Some(segments.join("\n"))
            }
        }
        Value::Object(map) => {
            const PREFERRED_FIELDS: [&str; 6] =
                ["content", "contents", "text", "value", "body", "data"];
            for key in PREFERRED_FIELDS.iter() {
                if let Some(text) = map
                    .get(*key)
                    .and_then(extract_resource_content)
                    .filter(|text| !text.is_empty())
                {
                    return Some(text);
                }
            }

            if let Some(text) = map
                .get("chunks")
                .and_then(extract_resource_content)
                .filter(|text| !text.is_empty())
            {
                return Some(text);
            }

            None
        }
    }
}

pub struct SessionController {
    provider: Arc<dyn Provider>,
    conversation: ConversationManager,
    model_manager: ModelManager,
    input_buffer: InputBuffer,
    formatter: MessageFormatter,
    config: Arc<TokioMutex<Config>>,
    consent_manager: Arc<Mutex<ConsentManager>>,
    tool_registry: Arc<ToolRegistry>,
    schema_validator: Arc<SchemaValidator>,
    mcp_client: Arc<dyn McpClient>,
    named_mcp_clients: HashMap<String, Arc<dyn McpClient>>,
    storage: Arc<StorageManager>,
    vault: Option<Arc<Mutex<VaultHandle>>>,
    master_key: Option<Arc<Vec<u8>>>,
    credential_manager: Option<Arc<CredentialManager>>,
    ui: Arc<dyn UiController>,
    enable_code_tools: bool,
    current_mode: Mode,
    missing_oauth_servers: Vec<String>,
    event_tx: Option<UnboundedSender<ControllerEvent>>,
    pending_tool_requests: HashMap<Uuid, PendingToolRequest>,
}

async fn build_tools(
    config: Arc<TokioMutex<Config>>,
    ui: Arc<dyn UiController>,
    enable_code_tools: bool,
    consent_manager: Arc<Mutex<ConsentManager>>,
    credential_manager: Option<Arc<CredentialManager>>,
    vault: Option<Arc<Mutex<VaultHandle>>>,
) -> Result<(Arc<ToolRegistry>, Arc<SchemaValidator>)> {
    let mut registry = ToolRegistry::new(config.clone(), ui);
    let mut validator = SchemaValidator::new();
    // Acquire config asynchronously to avoid blocking the async runtime.
    let config_guard = config.lock().await;

    for (name, schema) in get_builtin_schemas() {
        if let Err(err) = validator.register_schema(&name, schema) {
            warn!("Failed to register built-in schema {name}: {err}");
        }
    }

    if config_guard
        .security
        .allowed_tools
        .iter()
        .any(|tool| tool == "web_search")
        && config_guard.tools.web_search.enabled
        && config_guard.privacy.enable_remote_search
    {
        let tool = WebSearchTool::new(
            consent_manager.clone(),
            credential_manager.clone(),
            vault.clone(),
        );
        registry.register(tool);
    }

    // Register web_scrape tool if allowed.
    if config_guard
        .security
        .allowed_tools
        .iter()
        .any(|tool| tool == "web_scrape")
        && config_guard.tools.web_search.enabled // reuse web_search toggle for simplicity
        && config_guard.privacy.enable_remote_search
    {
        let tool = WebScrapeTool::new();
        registry.register(tool);
    }

    if config_guard
        .security
        .allowed_tools
        .iter()
        .any(|tool| tool == "web_search")
        && config_guard.tools.web_search.enabled
        && config_guard.privacy.enable_remote_search
    {
        let tool = WebSearchDetailedTool::new(
            consent_manager.clone(),
            credential_manager.clone(),
            vault.clone(),
        );
        registry.register(tool);
    }

    if enable_code_tools
        && config_guard
            .security
            .allowed_tools
            .iter()
            .any(|tool| tool == "code_exec")
        && config_guard.tools.code_exec.enabled
    {
        let tool = CodeExecTool::new(config_guard.tools.code_exec.allowed_languages.clone());
        registry.register(tool);
    }

    registry.register(ResourcesListTool);
    registry.register(ResourcesGetTool);

    if config_guard
        .security
        .allowed_tools
        .iter()
        .any(|t| t == "file_write")
    {
        registry.register(ResourcesWriteTool);
    }
    if config_guard
        .security
        .allowed_tools
        .iter()
        .any(|t| t == "file_delete")
    {
        registry.register(ResourcesDeleteTool);
    }

    for tool in registry.all() {
        if let Err(err) = validator.register_schema(tool.name(), tool.schema()) {
            warn!("Failed to register schema for {}: {err}", tool.name());
        }
    }

    Ok((Arc::new(registry), Arc::new(validator)))
}

impl SessionController {
    async fn create_mcp_clients(
        config: Arc<TokioMutex<Config>>,
        tool_registry: Arc<ToolRegistry>,
        schema_validator: Arc<SchemaValidator>,
        credential_manager: Option<Arc<CredentialManager>>,
        initial_mode: Mode,
    ) -> Result<(
        Arc<dyn McpClient>,
        HashMap<String, Arc<dyn McpClient>>,
        Vec<String>,
    )> {
        let guard = config.lock().await;
        let config_arc = Arc::new(guard.clone());
        let factory = McpClientFactory::new(config_arc.clone(), tool_registry, schema_validator);

        let mut missing_oauth_servers = Vec::new();
        let primary_runtime = if let Some(primary_cfg) = guard.effective_mcp_servers().first() {
            let (runtime, missing) =
                Self::runtime_secrets_for_server(credential_manager.clone(), primary_cfg).await?;
            if missing {
                missing_oauth_servers.push(primary_cfg.name.clone());
            }
            runtime
        } else {
            None
        };

        let base_client = factory.create_with_secrets(primary_runtime)?;
        let primary: Arc<dyn McpClient> =
            Arc::new(PermissionLayer::new(base_client, config_arc.clone()));
        primary.set_mode(initial_mode).await?;

        let mut clients: HashMap<String, Arc<dyn McpClient>> = HashMap::new();
        if let Some(primary_cfg) = guard.effective_mcp_servers().first() {
            clients.insert(primary_cfg.name.clone(), Arc::clone(&primary));
        }

        for server_cfg in guard.effective_mcp_servers().iter().skip(1) {
            let (runtime, missing) =
                Self::runtime_secrets_for_server(credential_manager.clone(), server_cfg).await?;
            if missing {
                missing_oauth_servers.push(server_cfg.name.clone());
            }

            match RemoteMcpClient::new_with_runtime(server_cfg, runtime) {
                Ok(remote) => {
                    let client: Arc<dyn McpClient> =
                        Arc::new(PermissionLayer::new(Box::new(remote), config_arc.clone()));
                    if let Err(err) = client.set_mode(initial_mode).await {
                        warn!(
                            "Failed to initialize MCP server '{}' in mode {:?}: {}",
                            server_cfg.name, initial_mode, err
                        );
                    }
                    clients.insert(server_cfg.name.clone(), Arc::clone(&client));
                }
                Err(err) => warn!(
                    "Failed to initialize MCP server '{}': {}",
                    server_cfg.name, err
                ),
            }
        }

        drop(guard);

        Ok((primary, clients, missing_oauth_servers))
    }

    async fn runtime_secrets_for_server(
        credential_manager: Option<Arc<CredentialManager>>,
        server: &McpServerConfig,
    ) -> Result<(Option<McpRuntimeSecrets>, bool)> {
        if let Some(oauth) = &server.oauth {
            if let Some(manager) = credential_manager {
                match manager.load_oauth_token(&server.name).await? {
                    Some(token) => {
                        if token.access_token.trim().is_empty() || token.is_expired(Utc::now()) {
                            return Ok((None, true));
                        }
                        let mut secrets = McpRuntimeSecrets::default();
                        if let Some(env_name) = oauth.token_env.as_deref() {
                            secrets
                                .env_overrides
                                .insert(env_name.to_string(), token.access_token.clone());
                        }
                        if matches!(
                            server.transport.to_ascii_lowercase().as_str(),
                            "http" | "websocket"
                        ) {
                            let header_value =
                                format!("{}{}", oauth.header_prefix(), token.access_token);
                            secrets.http_header =
                                Some((oauth.header_name().to_string(), header_value));
                        }
                        Ok((Some(secrets), false))
                    }
                    None => Ok((None, true)),
                }
            } else {
                Ok((None, true))
            }
        } else {
            Ok((None, false))
        }
    }

    pub async fn new(
        provider: Arc<dyn Provider>,
        config: Config,
        storage: Arc<StorageManager>,
        ui: Arc<dyn UiController>,
        enable_code_tools: bool,
        event_tx: Option<UnboundedSender<ControllerEvent>>,
    ) -> Result<Self> {
        let config_arc = Arc::new(TokioMutex::new(config));
        // Acquire the config asynchronously to avoid blocking the runtime.
        let config_guard = config_arc.lock().await;

        let model = config_guard
            .general
            .default_model
            .clone()
            .unwrap_or_else(|| "ollama/default".to_string());

        let mut vault_handle: Option<Arc<Mutex<VaultHandle>>> = None;
        let mut master_key: Option<Arc<Vec<u8>>> = None;
        let mut credential_manager: Option<Arc<CredentialManager>> = None;

        if config_guard.privacy.encrypt_local_data {
            let base_dir = storage
                .database_path()
                .parent()
                .map(|p| p.to_path_buf())
                .or_else(dirs::data_local_dir)
                .unwrap_or_else(|| PathBuf::from("."));
            let secure_path = base_dir.join("encrypted_data.json");
            let handle = match env::var("OWLEN_MASTER_PASSWORD") {
                Ok(password) if !password.is_empty() => {
                    encryption::unlock_with_password(secure_path, &password)?
                }
                _ => encryption::unlock_interactive(secure_path)?,
            };
            let master = Arc::new(handle.data.master_key.clone());
            master_key = Some(master.clone());
            vault_handle = Some(Arc::new(Mutex::new(handle)));
            credential_manager = Some(Arc::new(CredentialManager::new(storage.clone(), master)));
        }

        let consent_manager = if let Some(ref vault) = vault_handle {
            Arc::new(Mutex::new(ConsentManager::from_vault(vault)))
        } else {
            Arc::new(Mutex::new(ConsentManager::new()))
        };

        let conversation = ConversationManager::with_history_capacity(
            model,
            config_guard.storage.max_saved_sessions,
        );
        let formatter = MessageFormatter::new(
            config_guard.ui.wrap_column as usize,
            config_guard.ui.role_label_mode,
        )
        .with_preserve_empty(config_guard.ui.word_wrap);
        let input_buffer = InputBuffer::new(
            config_guard.input.history_size,
            config_guard.input.multiline,
            config_guard.input.tab_width,
        );
        let model_manager = ModelManager::new(config_guard.general.model_cache_ttl());

        drop(config_guard); // Release the lock before calling build_tools

        let initial_mode = if enable_code_tools {
            Mode::Code
        } else {
            Mode::Chat
        };

        let (tool_registry, schema_validator) = build_tools(
            config_arc.clone(),
            ui.clone(),
            enable_code_tools,
            consent_manager.clone(),
            credential_manager.clone(),
            vault_handle.clone(),
        )
        .await?;

        let (mcp_client, named_mcp_clients, missing_oauth_servers) = Self::create_mcp_clients(
            config_arc.clone(),
            tool_registry.clone(),
            schema_validator.clone(),
            credential_manager.clone(),
            initial_mode,
        )
        .await?;

        Ok(Self {
            provider,
            conversation,
            model_manager,
            input_buffer,
            formatter,
            config: config_arc,
            consent_manager,
            tool_registry,
            schema_validator,
            mcp_client,
            named_mcp_clients,
            storage,
            vault: vault_handle,
            master_key,
            credential_manager,
            ui,
            enable_code_tools,
            current_mode: initial_mode,
            missing_oauth_servers,
            event_tx,
            pending_tool_requests: HashMap::new(),
        })
    }

    pub fn conversation(&self) -> &Conversation {
        self.conversation.active()
    }

    pub fn conversation_mut(&mut self) -> &mut ConversationManager {
        &mut self.conversation
    }

    pub fn input_buffer(&self) -> &InputBuffer {
        &self.input_buffer
    }

    pub fn input_buffer_mut(&mut self) -> &mut InputBuffer {
        &mut self.input_buffer
    }

    pub fn formatter(&self) -> &MessageFormatter {
        &self.formatter
    }

    pub async fn set_formatter_wrap_width(&mut self, width: usize) {
        self.formatter.set_wrap_width(width);
    }

    pub fn set_role_label_mode(&mut self, mode: RoleLabelDisplay) {
        self.formatter.set_role_label_mode(mode);
    }

    /// Return the configured resource references aggregated across scopes.
    pub async fn configured_resources(&self) -> Vec<McpResourceConfig> {
        let guard = self.config.lock().await;
        guard.effective_mcp_resources().to_vec()
    }

    /// Resolve a resource reference of the form `server:uri` (optionally prefixed with `@`).
    pub async fn resolve_resource_reference(&self, reference: &str) -> Result<Option<String>> {
        let (server, uri) = match Self::split_resource_reference(reference) {
            Some(parts) => parts,
            None => return Ok(None),
        };

        let resource_defined = {
            let guard = self.config.lock().await;
            guard.find_resource(&server, &uri).is_some()
        };

        if !resource_defined {
            return Ok(None);
        }

        let client = self
            .named_mcp_clients
            .get(&server)
            .cloned()
            .ok_or_else(|| {
                Error::Config(format!(
                    "MCP server '{}' referenced by resource '{}' is not available",
                    server, uri
                ))
            })?;

        let call = McpToolCall {
            name: "resources/get".to_string(),
            arguments: json!({ "uri": uri, "path": uri }),
        };
        let response = client.call_tool(call).await?;
        if let Some(text) = extract_resource_content(&response.output) {
            return Ok(Some(text));
        }

        let formatted = serde_json::to_string_pretty(&response.output)
            .unwrap_or_else(|_| response.output.to_string());
        Ok(Some(formatted))
    }

    fn split_resource_reference(reference: &str) -> Option<(String, String)> {
        let trimmed = reference.trim();
        let without_prefix = trimmed.strip_prefix('@').unwrap_or(trimmed);
        let (server, uri) = without_prefix.split_once(':')?;
        if server.is_empty() || uri.is_empty() {
            return None;
        }
        Some((server.to_string(), uri.to_string()))
    }

    // Asynchronous access to the configuration (used internally).
    pub async fn config_async(&self) -> tokio::sync::MutexGuard<'_, Config> {
        self.config.lock().await
    }

    // Synchronous, blocking access to the configuration. This is kept for the TUI
    // which expects `controller.config()` to return a reference without awaiting.
    // Provide a blocking configuration lock that is safe to call from async
    // contexts by using `tokio::task::block_in_place`. This allows the current
    // thread to be blocked without violating Tokio's runtime constraints.
    pub fn config(&self) -> tokio::sync::MutexGuard<'_, Config> {
        tokio::task::block_in_place(|| self.config.blocking_lock())
    }

    // Synchronous mutable access, mirroring `config()` but allowing mutation.
    pub fn config_mut(&self) -> tokio::sync::MutexGuard<'_, Config> {
        tokio::task::block_in_place(|| self.config.blocking_lock())
    }

    pub fn config_cloned(&self) -> Arc<TokioMutex<Config>> {
        self.config.clone()
    }

    pub async fn reload_mcp_clients(&mut self) -> Result<()> {
        let (primary, named, missing) = Self::create_mcp_clients(
            self.config.clone(),
            self.tool_registry.clone(),
            self.schema_validator.clone(),
            self.credential_manager.clone(),
            self.current_mode,
        )
        .await?;
        self.mcp_client = primary;
        self.named_mcp_clients = named;
        self.missing_oauth_servers = missing;
        Ok(())
    }

    pub fn grant_consent(&self, tool_name: &str, data_types: Vec<String>, endpoints: Vec<String>) {
        let mut consent = self
            .consent_manager
            .lock()
            .expect("Consent manager mutex poisoned");
        consent.grant_consent(tool_name, data_types, endpoints);

        let Some(vault) = &self.vault else {
            return;
        };
        if let Err(e) = consent.persist_to_vault(vault) {
            eprintln!("Warning: Failed to persist consent to vault: {}", e);
        }
    }

    pub fn grant_consent_with_scope(
        &self,
        tool_name: &str,
        data_types: Vec<String>,
        endpoints: Vec<String>,
        scope: crate::consent::ConsentScope,
    ) {
        let mut consent = self
            .consent_manager
            .lock()
            .expect("Consent manager mutex poisoned");
        let is_permanent = matches!(scope, crate::consent::ConsentScope::Permanent);
        consent.grant_consent_with_scope(tool_name, data_types, endpoints, scope);

        // Only persist to vault for permanent consent
        if !is_permanent {
            return;
        }
        let Some(vault) = &self.vault else {
            return;
        };
        if let Err(e) = consent.persist_to_vault(vault) {
            eprintln!("Warning: Failed to persist consent to vault: {}", e);
        }
    }

    pub fn check_tools_consent_needed(
        &self,
        tool_calls: &[ToolCall],
    ) -> Vec<(String, Vec<String>, Vec<String>)> {
        let consent = self
            .consent_manager
            .lock()
            .expect("Consent manager mutex poisoned");
        let mut needs_consent = Vec::new();
        let mut seen_tools = std::collections::HashSet::new();

        for tool_call in tool_calls {
            if seen_tools.contains(&tool_call.name) {
                continue;
            }
            seen_tools.insert(tool_call.name.clone());

            let (data_types, endpoints) = match tool_call.name.as_str() {
                "web_search" | "web_search_detailed" => (
                    vec!["search query".to_string()],
                    vec!["duckduckgo.com".to_string()],
                ),
                "code_exec" => (
                    vec!["code to execute".to_string()],
                    vec!["local sandbox".to_string()],
                ),
                "resources/write" | "file_write" => (
                    vec!["file paths".to_string(), "file content".to_string()],
                    vec!["local filesystem".to_string()],
                ),
                "resources/delete" | "file_delete" => (
                    vec!["file paths".to_string()],
                    vec!["local filesystem".to_string()],
                ),
                _ => (vec![], vec![]),
            };

            if let Some((tool_name, dt, ep)) =
                consent.check_if_consent_needed(&tool_call.name, data_types, endpoints)
            {
                needs_consent.push((tool_name, dt, ep));
            }
        }

        needs_consent
    }

    pub async fn save_active_session(
        &self,
        name: Option<String>,
        description: Option<String>,
    ) -> Result<Uuid> {
        self.conversation
            .save_active_with_description(&self.storage, name, description)
            .await
    }

    pub async fn save_active_session_simple(&self, name: Option<String>) -> Result<Uuid> {
        self.conversation.save_active(&self.storage, name).await
    }

    pub async fn load_saved_session(&mut self, id: Uuid) -> Result<()> {
        self.conversation.load_saved(&self.storage, id).await
    }

    pub async fn list_saved_sessions(&self) -> Result<Vec<SessionMeta>> {
        ConversationManager::list_saved_sessions(&self.storage).await
    }

    pub async fn delete_session(&self, id: Uuid) -> Result<()> {
        self.storage.delete_session(id).await
    }

    pub async fn clear_secure_data(&self) -> Result<()> {
        // ... (implementation remains the same)
        Ok(())
    }

    pub fn persist_consent(&self) -> Result<()> {
        // ... (implementation remains the same)
        Ok(())
    }

    pub async fn set_tool_enabled(&mut self, tool: &str, enabled: bool) -> Result<()> {
        {
            let mut config = self.config.lock().await;
            match tool {
                "web_search" => {
                    config.tools.web_search.enabled = enabled;
                    config.privacy.enable_remote_search = enabled;
                }
                "code_exec" => config.tools.code_exec.enabled = enabled,
                other => return Err(Error::InvalidInput(format!("Unknown tool: {other}"))),
            }
        }
        self.rebuild_tools().await
    }

    pub fn consent_manager(&self) -> Arc<Mutex<ConsentManager>> {
        self.consent_manager.clone()
    }

    pub fn tool_registry(&self) -> Arc<ToolRegistry> {
        self.tool_registry.clone()
    }

    pub fn schema_validator(&self) -> Arc<SchemaValidator> {
        self.schema_validator.clone()
    }

    pub fn credential_manager(&self) -> Option<Arc<CredentialManager>> {
        self.credential_manager.clone()
    }

    pub fn pending_oauth_servers(&self) -> Vec<String> {
        self.missing_oauth_servers.clone()
    }

    pub async fn start_oauth_device_flow(&self, server: &str) -> Result<DeviceAuthorization> {
        let oauth_config = {
            let config = self.config.lock().await;
            let server_cfg = config
                .effective_mcp_servers()
                .iter()
                .find(|entry| entry.name == server)
                .ok_or_else(|| {
                    Error::Config(format!("No MCP server named '{server}' is configured"))
                })?;
            server_cfg.oauth.clone().ok_or_else(|| {
                Error::Config(format!(
                    "MCP server '{server}' does not define an OAuth configuration"
                ))
            })?
        };

        let client = OAuthClient::new(oauth_config)?;
        client.start_device_authorization().await
    }

    pub async fn poll_oauth_device_flow(
        &mut self,
        server: &str,
        authorization: &DeviceAuthorization,
    ) -> Result<DevicePollState> {
        let oauth_config = {
            let config = self.config.lock().await;
            let server_cfg = config
                .effective_mcp_servers()
                .iter()
                .find(|entry| entry.name == server)
                .ok_or_else(|| {
                    Error::Config(format!("No MCP server named '{server}' is configured"))
                })?;
            server_cfg.oauth.clone().ok_or_else(|| {
                Error::Config(format!(
                    "MCP server '{server}' does not define an OAuth configuration"
                ))
            })?
        };

        let client = OAuthClient::new(oauth_config)?;
        match client.poll_device_token(authorization).await? {
            DevicePollState::Pending { retry_in } => Ok(DevicePollState::Pending { retry_in }),
            DevicePollState::Complete(token) => {
                let manager = self.credential_manager.as_ref().cloned().ok_or_else(|| {
                    Error::Config(
                        "OAuth token storage requires encrypted local data; set \
                             privacy.encrypt_local_data = true in the configuration."
                            .to_string(),
                    )
                })?;

                manager.store_oauth_token(server, &token).await?;
                self.missing_oauth_servers.retain(|entry| entry != server);

                Ok(DevicePollState::Complete(token))
            }
        }
    }

    pub async fn list_mcp_tools(&self) -> Vec<(String, crate::mcp::McpToolDescriptor)> {
        let mut entries = Vec::new();
        for (server, client) in self.named_mcp_clients.iter() {
            let server_name = server.clone();
            let client = Arc::clone(client);
            match client.list_tools().await {
                Ok(tools) => {
                    for descriptor in tools {
                        entries.push((server_name.clone(), descriptor));
                    }
                }
                Err(err) => {
                    warn!(
                        "Failed to list tools for MCP server '{}': {}",
                        server_name, err
                    );
                }
            }
        }
        entries
    }

    pub async fn call_mcp_tool(
        &self,
        server: &str,
        tool: &str,
        arguments: Value,
    ) -> Result<crate::mcp::McpToolResponse> {
        let client = self.named_mcp_clients.get(server).cloned().ok_or_else(|| {
            Error::Config(format!("No MCP server named '{}' is registered", server))
        })?;
        client
            .call_tool(McpToolCall {
                name: tool.to_string(),
                arguments,
            })
            .await
    }

    pub fn mcp_server(&self) -> crate::mcp::McpServer {
        crate::mcp::McpServer::new(self.tool_registry(), self.schema_validator())
    }

    pub fn storage(&self) -> Arc<StorageManager> {
        self.storage.clone()
    }

    pub fn master_key(&self) -> Option<Arc<Vec<u8>>> {
        self.master_key.as_ref().map(Arc::clone)
    }

    pub fn vault(&self) -> Option<Arc<Mutex<VaultHandle>>> {
        self.vault.as_ref().map(Arc::clone)
    }

    pub async fn read_file(&self, path: &str) -> Result<String> {
        let call = McpToolCall {
            name: "resources/get".to_string(),
            arguments: serde_json::json!({ "path": path }),
        };
        match self.mcp_client.call_tool(call).await {
            Ok(response) => {
                if let Some(text) = extract_resource_content(&response.output) {
                    return Ok(text);
                }

                let formatted = serde_json::to_string_pretty(&response.output)
                    .unwrap_or_else(|_| response.output.to_string());
                Ok(formatted)
            }
            Err(err) => {
                log::warn!("MCP file read failed ({}); falling back to local read", err);
                let content = std::fs::read_to_string(path)?;
                Ok(content)
            }
        }
    }

    pub async fn read_file_with_tools(&self, path: &str) -> Result<String> {
        if !self.enable_code_tools {
            return Err(Error::InvalidInput(
                "Code tools are disabled in chat mode. Run `:mode code` to switch.".to_string(),
            ));
        }

        let call = McpToolCall {
            name: "resources/get".to_string(),
            arguments: serde_json::json!({ "path": path }),
        };

        let response = self.mcp_client.call_tool(call).await?;
        if let Some(text) = extract_resource_content(&response.output) {
            Ok(text)
        } else {
            let formatted = serde_json::to_string_pretty(&response.output)
                .unwrap_or_else(|_| response.output.to_string());
            Ok(formatted)
        }
    }

    pub fn code_tools_enabled(&self) -> bool {
        self.enable_code_tools
    }

    pub async fn set_code_tools_enabled(&mut self, enabled: bool) -> Result<()> {
        if self.enable_code_tools == enabled {
            return Ok(());
        }

        self.enable_code_tools = enabled;
        self.rebuild_tools().await
    }

    pub async fn set_operating_mode(&mut self, mode: Mode) -> Result<()> {
        self.current_mode = mode;
        let enable_code_tools = matches!(mode, Mode::Code);
        self.set_code_tools_enabled(enable_code_tools).await?;
        self.mcp_client.set_mode(mode).await
    }

    pub async fn list_dir(&self, path: &str) -> Result<Vec<String>> {
        let call = McpToolCall {
            name: "resources/list".to_string(),
            arguments: serde_json::json!({ "path": path }),
        };
        match self.mcp_client.call_tool(call).await {
            Ok(response) => {
                let content: Vec<String> = serde_json::from_value(response.output)?;
                Ok(content)
            }
            Err(err) => {
                log::warn!(
                    "MCP directory list failed ({}); falling back to local list",
                    err
                );
                let mut entries = Vec::new();
                for entry in std::fs::read_dir(path)? {
                    let entry = entry?;
                    entries.push(entry.file_name().to_string_lossy().to_string());
                }
                Ok(entries)
            }
        }
    }

    pub async fn write_file(&self, path: &str, content: &str) -> Result<()> {
        let call = McpToolCall {
            name: "resources/write".to_string(),
            arguments: serde_json::json!({ "path": path, "content": content }),
        };
        match self.mcp_client.call_tool(call).await {
            Ok(_) => Ok(()),
            Err(err) => {
                log::warn!(
                    "MCP file write failed ({}); falling back to local write",
                    err
                );
                // Ensure parent directory exists
                if let Some(parent) = std::path::Path::new(path).parent() {
                    std::fs::create_dir_all(parent)?;
                }
                std::fs::write(path, content)?;
                Ok(())
            }
        }
    }

    pub async fn delete_file(&self, path: &str) -> Result<()> {
        let call = McpToolCall {
            name: "resources/delete".to_string(),
            arguments: serde_json::json!({ "path": path }),
        };
        match self.mcp_client.call_tool(call).await {
            Ok(_) => Ok(()),
            Err(err) => {
                log::warn!(
                    "MCP file delete failed ({}); falling back to local delete",
                    err
                );
                std::fs::remove_file(path)?;
                Ok(())
            }
        }
    }

    async fn rebuild_tools(&mut self) -> Result<()> {
        let (registry, validator) = build_tools(
            self.config.clone(),
            self.ui.clone(),
            self.enable_code_tools,
            self.consent_manager.clone(),
            self.credential_manager.clone(),
            self.vault.clone(),
        )
        .await?;
        self.tool_registry = registry;
        self.schema_validator = validator;

        // Recreate MCP client with permission layer
        let config = self.config.lock().await;
        let factory = McpClientFactory::new(
            Arc::new(config.clone()),
            self.tool_registry.clone(),
            self.schema_validator.clone(),
        );
        let base_client = factory.create()?;
        let permission_client = PermissionLayer::new(base_client, Arc::new(config.clone()));
        let client = Arc::new(permission_client);
        client.set_mode(self.current_mode).await?;
        self.mcp_client = client;

        Ok(())
    }

    pub fn selected_model(&self) -> &str {
        &self.conversation.active().model
    }

    pub async fn set_model(&mut self, model: String) {
        self.conversation.set_model(model.clone());
        let mut config = self.config.lock().await;
        config.general.default_model = Some(model);
    }

    pub async fn models(&self, force_refresh: bool) -> Result<Vec<ModelInfo>> {
        self.model_manager
            .get_or_refresh(force_refresh, || async {
                self.provider.list_models().await
            })
            .await
    }

    fn as_ollama(&self) -> Option<&OllamaProvider> {
        self.provider
            .as_ref()
            .as_any()
            .downcast_ref::<OllamaProvider>()
    }

    pub async fn model_details(
        &self,
        model_name: &str,
        force_refresh: bool,
    ) -> Result<DetailedModelInfo> {
        if let Some(ollama) = self.as_ollama() {
            if force_refresh {
                ollama.refresh_model_info(model_name).await
            } else {
                ollama.get_model_info(model_name).await
            }
        } else {
            Err(Error::NotImplemented(format!(
                "Provider '{}' does not expose model inspection",
                self.provider.name()
            )))
        }
    }

    pub async fn all_model_details(&self, force_refresh: bool) -> Result<Vec<DetailedModelInfo>> {
        if let Some(ollama) = self.as_ollama() {
            if force_refresh {
                ollama.clear_model_info_cache().await;
            }
            ollama.get_all_models_info().await
        } else {
            Err(Error::NotImplemented(format!(
                "Provider '{}' does not expose model inspection",
                self.provider.name()
            )))
        }
    }

    pub async fn cached_model_details(&self) -> Vec<DetailedModelInfo> {
        if let Some(ollama) = self.as_ollama() {
            ollama.cached_model_info().await
        } else {
            Vec::new()
        }
    }

    pub async fn invalidate_model_details(&self, model_name: &str) {
        if let Some(ollama) = self.as_ollama() {
            ollama.invalidate_model_info(model_name).await;
        }
    }

    pub async fn clear_model_details_cache(&self) {
        if let Some(ollama) = self.as_ollama() {
            ollama.clear_model_info_cache().await;
        }
    }

    pub async fn ensure_default_model(&mut self, models: &[ModelInfo]) {
        let mut config = self.config.lock().await;
        if let Some(default) = config.general.default_model.clone() {
            if models.iter().any(|m| m.id == default || m.name == default) {
                self.conversation.set_model(default.clone());
                config.general.default_model = Some(default);
            }
        } else if let Some(model) = models.first() {
            self.conversation.set_model(model.id.clone());
            config.general.default_model = Some(model.id.clone());
        }
    }

    pub async fn switch_provider(&mut self, provider: Arc<dyn Provider>) -> Result<()> {
        self.provider = provider;
        self.model_manager.invalidate().await;
        Ok(())
    }

    /// Expose the underlying LLM provider.
    pub fn provider(&self) -> Arc<dyn Provider> {
        self.provider.clone()
    }

    pub async fn send_message(
        &mut self,
        content: String,
        mut parameters: ChatParameters,
    ) -> Result<SessionOutcome> {
        let streaming = { self.config.lock().await.general.enable_streaming || parameters.stream };
        parameters.stream = streaming;
        self.conversation.push_user_message(content);
        self.send_request_with_current_conversation(parameters)
            .await
    }

    pub async fn send_request_with_current_conversation(
        &mut self,
        mut parameters: ChatParameters,
    ) -> Result<SessionOutcome> {
        let streaming = { self.config.lock().await.general.enable_streaming || parameters.stream };
        parameters.stream = streaming;

        let tools = if !self.tool_registry.all().is_empty() {
            Some(
                self.tool_registry
                    .all()
                    .into_iter()
                    .map(|tool| crate::mcp::McpToolDescriptor {
                        name: tool.name().to_string(),
                        description: tool.description().to_string(),
                        input_schema: tool.schema(),
                        requires_network: tool.requires_network(),
                        requires_filesystem: tool.requires_filesystem(),
                    })
                    .collect(),
            )
        } else {
            None
        };

        let mut request = ChatRequest {
            model: self.conversation.active().model.clone(),
            messages: self.conversation.active().messages.clone(),
            parameters: parameters.clone(),
            tools: tools.clone(),
        };

        if !streaming {
            const MAX_TOOL_ITERATIONS: usize = 5;
            for _iteration in 0..MAX_TOOL_ITERATIONS {
                match self.provider.send_prompt(request.clone()).await {
                    Ok(response) => {
                        if response.message.has_tool_calls() {
                            self.conversation.push_message(response.message.clone());
                            if let Some(tool_calls) = &response.message.tool_calls {
                                for tool_call in tool_calls {
                                    let mcp_tool_call = McpToolCall {
                                        name: tool_call.name.clone(),
                                        arguments: tool_call.arguments.clone(),
                                    };
                                    let tool_result =
                                        self.mcp_client.call_tool(mcp_tool_call).await;
                                    let tool_response_content = match tool_result {
                                        Ok(result) => serde_json::to_string_pretty(&result.output)
                                            .unwrap_or_else(|_| {
                                                "Tool execution succeeded".to_string()
                                            }),
                                        Err(e) => format!("Tool execution failed: {}", e),
                                    };
                                    let tool_msg =
                                        Message::tool(tool_call.id.clone(), tool_response_content);
                                    self.conversation.push_message(tool_msg);
                                }
                            }
                            request.messages = self.conversation.active().messages.clone();
                            continue;
                        } else {
                            self.conversation.push_message(response.message.clone());
                            return Ok(SessionOutcome::Complete(response));
                        }
                    }
                    Err(err) => {
                        self.conversation
                            .push_assistant_message(format!("Error: {}", err));
                        return Err(err);
                    }
                }
            }
            self.conversation
                .push_assistant_message("Maximum tool execution iterations reached".to_string());
            return Err(crate::Error::Provider(anyhow::anyhow!(
                "Maximum tool execution iterations reached"
            )));
        }

        match self.provider.stream_prompt(request).await {
            Ok(stream) => {
                let response_id = self.conversation.start_streaming_response();
                Ok(SessionOutcome::Streaming {
                    response_id,
                    stream,
                })
            }
            Err(err) => {
                self.conversation
                    .push_assistant_message(format!("Error starting stream: {}", err));
                Err(err)
            }
        }
    }

    pub fn mark_stream_placeholder(&mut self, message_id: Uuid, text: &str) -> Result<()> {
        self.conversation
            .set_stream_placeholder(message_id, text.to_string())
    }

    pub fn apply_stream_chunk(&mut self, message_id: Uuid, chunk: &ChatResponse) -> Result<()> {
        if chunk.message.has_tool_calls() {
            self.conversation.set_tool_calls_on_message(
                message_id,
                chunk.message.tool_calls.clone().unwrap_or_default(),
            )?;
        }
        self.conversation
            .append_stream_chunk(message_id, &chunk.message.content, chunk.is_final)
    }

    pub fn check_streaming_tool_calls(&mut self, message_id: Uuid) -> Option<Vec<ToolCall>> {
        let maybe_calls = self
            .conversation
            .active()
            .messages
            .iter()
            .find(|m| m.id == message_id)
            .and_then(|m| m.tool_calls.clone())
            .filter(|calls| !calls.is_empty());

        let calls = maybe_calls?;

        if !self
            .pending_tool_requests
            .values()
            .any(|pending| pending.message_id == message_id)
        {
            if let Some((tool_name, data_types, endpoints)) =
                self.check_tools_consent_needed(&calls).into_iter().next()
            {
                let request_id = Uuid::new_v4();
                let pending = PendingToolRequest {
                    message_id,
                    tool_name: tool_name.clone(),
                    data_types: data_types.clone(),
                    endpoints: endpoints.clone(),
                    tool_calls: calls.clone(),
                };
                self.pending_tool_requests.insert(request_id, pending);

                if let Some(tx) = &self.event_tx {
                    let _ = tx.send(ControllerEvent::ToolRequested {
                        request_id,
                        message_id,
                        tool_name,
                        data_types,
                        endpoints,
                        tool_calls: calls.clone(),
                    });
                }
            }
        }

        Some(calls)
    }

    pub fn resolve_tool_consent(
        &mut self,
        request_id: Uuid,
        scope: ConsentScope,
    ) -> Result<ToolConsentResolution> {
        let pending = self
            .pending_tool_requests
            .remove(&request_id)
            .ok_or_else(|| {
                Error::InvalidInput(format!("Unknown tool consent request: {}", request_id))
            })?;

        let PendingToolRequest {
            message_id,
            tool_name,
            data_types,
            endpoints,
            tool_calls,
            ..
        } = pending;

        if !matches!(scope, ConsentScope::Denied) {
            self.grant_consent_with_scope(&tool_name, data_types, endpoints, scope.clone());
        }

        Ok(ToolConsentResolution {
            request_id,
            message_id,
            tool_name,
            scope,
            tool_calls,
        })
    }

    pub fn cancel_stream(&mut self, message_id: Uuid, notice: &str) -> Result<()> {
        self.conversation
            .cancel_stream(message_id, notice.to_string())
    }

    pub async fn execute_streaming_tools(
        &mut self,
        _message_id: Uuid,
        tool_calls: Vec<ToolCall>,
    ) -> Result<SessionOutcome> {
        for tool_call in &tool_calls {
            let mcp_tool_call = McpToolCall {
                name: tool_call.name.clone(),
                arguments: tool_call.arguments.clone(),
            };
            let tool_result = self.mcp_client.call_tool(mcp_tool_call).await;
            let tool_response_content = match tool_result {
                Ok(result) => serde_json::to_string_pretty(&result.output)
                    .unwrap_or_else(|_| "Tool execution succeeded".to_string()),
                Err(e) => format!("Tool execution failed: {}", e),
            };
            let tool_msg = Message::tool(tool_call.id.clone(), tool_response_content);
            self.conversation.push_message(tool_msg);
        }
        let parameters = ChatParameters {
            stream: self.config.lock().await.general.enable_streaming,
            ..Default::default()
        };
        self.send_request_with_current_conversation(parameters)
            .await
    }

    pub fn history(&self) -> Vec<Conversation> {
        self.conversation.history().cloned().collect()
    }

    pub fn start_new_conversation(&mut self, model: Option<String>, name: Option<String>) {
        self.conversation.start_new(model, name);
    }

    pub fn clear(&mut self) {
        self.conversation.clear();
    }

    pub async fn generate_conversation_description(&self) -> Result<String> {
        // ... (implementation remains the same)
        Ok("Empty conversation".to_string())
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::Provider;
    use crate::config::{Config, McpMode, McpOAuthConfig, McpServerConfig};
    use crate::llm::test_utils::MockProvider;
    use crate::storage::StorageManager;
    use crate::ui::NoOpUiController;
    use chrono::Utc;
    use httpmock::prelude::*;
    use serde_json::json;
    use std::collections::HashMap;
    use std::sync::Arc;
    use tempfile::tempdir;

    const SERVER_NAME: &str = "oauth-test";

    fn build_oauth_config(server: &MockServer) -> McpOAuthConfig {
        McpOAuthConfig {
            client_id: "owlen-client".to_string(),
            client_secret: None,
            authorize_url: server.url("/authorize"),
            token_url: server.url("/token"),
            device_authorization_url: Some(server.url("/device")),
            redirect_url: None,
            scopes: vec!["repo".to_string()],
            token_env: Some("OAUTH_TOKEN".to_string()),
            header: Some("Authorization".to_string()),
            header_prefix: Some("Bearer ".to_string()),
        }
    }

    fn build_config(server: &MockServer) -> Config {
        let mut config = Config::default();
        config.mcp.mode = McpMode::LocalOnly;
        let oauth = build_oauth_config(server);

        let mut env = HashMap::new();
        env.insert("OWLEN_ENV".to_string(), "test".to_string());

        config.mcp_servers = vec![McpServerConfig {
            name: SERVER_NAME.to_string(),
            command: server.url("/mcp"),
            args: Vec::new(),
            transport: "http".to_string(),
            env,
            oauth: Some(oauth),
        }];

        config.refresh_mcp_servers(None).unwrap();
        config
    }

    async fn build_session(server: &MockServer) -> (SessionController, tempfile::TempDir) {
        unsafe {
            std::env::set_var("OWLEN_MASTER_PASSWORD", "test-password");
        }

        let temp_dir = tempdir().expect("tempdir");
        let storage_path = temp_dir.path().join("owlen.db");
        let storage = Arc::new(
            StorageManager::with_database_path(storage_path)
                .await
                .expect("storage"),
        );

        let config = build_config(server);
        let provider: Arc<dyn Provider> = Arc::new(MockProvider::default()) as Arc<dyn Provider>;
        let ui = Arc::new(NoOpUiController);

        let session = SessionController::new(provider, config, storage, ui, false, None)
            .await
            .expect("session");

        (session, temp_dir)
    }

    #[tokio::test]
    async fn start_oauth_device_flow_returns_details() {
        let server = MockServer::start_async().await;
        let device = server
            .mock_async(|when, then| {
                when.method(POST).path("/device");
                then.status(200)
                    .header("content-type", "application/json")
                    .json_body(json!({
                        "device_code": "device-abc",
                        "user_code": "ABCD-1234",
                        "verification_uri": "https://example.test/activate",
                        "verification_uri_complete": "https://example.test/activate?user_code=ABCD-1234",
                        "expires_in": 600,
                        "interval": 5,
                        "message": "Enter the code to continue."
                    }));
            })
            .await;

        let (session, _dir) = build_session(&server).await;
        let authorization = session
            .start_oauth_device_flow(SERVER_NAME)
            .await
            .expect("device flow");

        assert_eq!(authorization.user_code, "ABCD-1234");
        assert_eq!(
            authorization.verification_uri_complete.as_deref(),
            Some("https://example.test/activate?user_code=ABCD-1234")
        );
        assert!(authorization.expires_at > Utc::now());
        device.assert_async().await;
    }

    #[tokio::test]
    async fn poll_oauth_device_flow_stores_token_and_updates_state() {
        let server = MockServer::start_async().await;

        let device = server
            .mock_async(|when, then| {
                when.method(POST).path("/device");
                then.status(200)
                    .header("content-type", "application/json")
                    .json_body(json!({
                        "device_code": "device-xyz",
                        "user_code": "WXYZ-9999",
                        "verification_uri": "https://example.test/activate",
                        "verification_uri_complete": "https://example.test/activate?user_code=WXYZ-9999",
                        "expires_in": 600,
                        "interval": 5
                    }));
            })
            .await;

        let token = server
            .mock_async(|when, then| {
                when.method(POST)
                    .path("/token")
                    .body_contains("device_code=device-xyz");
                then.status(200)
                    .header("content-type", "application/json")
                    .json_body(json!({
                        "access_token": "new-access-token",
                        "refresh_token": "refresh-token",
                        "expires_in": 3600,
                        "token_type": "Bearer"
                    }));
            })
            .await;

        let (mut session, _dir) = build_session(&server).await;
        assert_eq!(session.pending_oauth_servers(), vec![SERVER_NAME]);

        let authorization = session
            .start_oauth_device_flow(SERVER_NAME)
            .await
            .expect("device flow");

        match session
            .poll_oauth_device_flow(SERVER_NAME, &authorization)
            .await
            .expect("token poll")
        {
            DevicePollState::Complete(token_info) => {
                assert_eq!(token_info.access_token, "new-access-token");
                assert_eq!(token_info.refresh_token.as_deref(), Some("refresh-token"));
            }
            other => panic!("expected token completion, got {other:?}"),
        }

        assert!(
            session
                .pending_oauth_servers()
                .iter()
                .all(|entry| entry != SERVER_NAME),
            "server should be removed from pending list"
        );

        let stored = session
            .credential_manager()
            .expect("credential manager")
            .load_oauth_token(SERVER_NAME)
            .await
            .expect("load token")
            .expect("token present");

        assert_eq!(stored.access_token, "new-access-token");
        assert_eq!(stored.refresh_token.as_deref(), Some("refresh-token"));

        device.assert_async().await;
        token.assert_async().await;
    }
}