//! Bot runner for executing tests
//!
//! Provides a test runner that can execute BASIC scripts and simulate
//! bot behavior for integration testing.

use super::{BotResponse, ConversationState, ResponseContentType};
use crate::fixtures::{Bot, Channel, Customer, Session};
use crate::harness::TestContext;
use anyhow::{Context, Result};
use std::collections::HashMap;
use std::path::PathBuf;
use std::sync::{Arc, Mutex};
use std::time::{Duration, Instant};
use uuid::Uuid;

/// Configuration for the bot runner
#[derive(Debug, Clone)]
pub struct BotRunnerConfig {
    /// Working directory for the bot
    pub working_dir: PathBuf,
    /// Maximum execution time for a single request
    pub timeout: Duration,
    /// Whether to use mock services
    pub use_mocks: bool,
    /// Environment variables to set
    pub env_vars: HashMap<String, String>,
    /// Whether to capture logs
    pub capture_logs: bool,
    /// Log level
    pub log_level: LogLevel,
}

impl Default for BotRunnerConfig {
    fn default() -> Self {
        Self {
            working_dir: std::env::temp_dir().join("bottest"),
            timeout: Duration::from_secs(30),
            use_mocks: true,
            env_vars: HashMap::new(),
            capture_logs: true,
            log_level: LogLevel::Info,
        }
    }
}

/// Log level for bot runner
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum LogLevel {
    Trace,
    Debug,
    Info,
    Warn,
    Error,
}

impl Default for LogLevel {
    fn default() -> Self {
        Self::Info
    }
}

/// Bot runner for executing bot scripts and simulating conversations
pub struct BotRunner {
    config: BotRunnerConfig,
    bot: Option<Bot>,
    sessions: Arc<Mutex<HashMap<Uuid, SessionState>>>,
    script_cache: Arc<Mutex<HashMap<String, String>>>,
    metrics: Arc<Mutex<RunnerMetrics>>,
}

/// Internal session state
struct SessionState {
    session: Session,
    customer: Customer,
    channel: Channel,
    context: HashMap<String, serde_json::Value>,
    conversation_state: ConversationState,
    message_count: usize,
    started_at: Instant,
}

/// Metrics collected by the runner
#[derive(Debug, Default, Clone)]
pub struct RunnerMetrics {
    pub total_requests: u64,
    pub successful_requests: u64,
    pub failed_requests: u64,
    pub total_latency_ms: u64,
    pub min_latency_ms: u64,
    pub max_latency_ms: u64,
    pub script_executions: u64,
    pub transfer_to_human_count: u64,
}

impl RunnerMetrics {
    /// Get average latency in milliseconds
    pub fn avg_latency_ms(&self) -> u64 {
        if self.total_requests > 0 {
            self.total_latency_ms / self.total_requests
        } else {
            0
        }
    }

    /// Get success rate as percentage
    pub fn success_rate(&self) -> f64 {
        if self.total_requests > 0 {
            (self.successful_requests as f64 / self.total_requests as f64) * 100.0
        } else {
            0.0
        }
    }
}

/// Result of a bot execution
#[derive(Debug, Clone)]
pub struct ExecutionResult {
    pub session_id: Uuid,
    pub response: Option<BotResponse>,
    pub state: ConversationState,
    pub execution_time: Duration,
    pub logs: Vec<LogEntry>,
    pub error: Option<String>,
}

/// A log entry captured during execution
#[derive(Debug, Clone)]
pub struct LogEntry {
    pub timestamp: chrono::DateTime<chrono::Utc>,
    pub level: LogLevel,
    pub message: String,
    pub context: HashMap<String, String>,
}

impl BotRunner {
    /// Create a new bot runner with default configuration
    pub fn new() -> Self {
        Self::with_config(BotRunnerConfig::default())
    }

    /// Create a new bot runner with custom configuration
    pub fn with_config(config: BotRunnerConfig) -> Self {
        Self {
            config,
            bot: None,
            sessions: Arc::new(Mutex::new(HashMap::new())),
            script_cache: Arc::new(Mutex::new(HashMap::new())),
            metrics: Arc::new(Mutex::new(RunnerMetrics::default())),
        }
    }

    /// Create a bot runner with a test context
    pub fn with_context(_ctx: &TestContext, config: BotRunnerConfig) -> Self {
        Self::with_config(config)
    }

    /// Set the bot to run
    pub fn set_bot(&mut self, bot: Bot) -> &mut Self {
        self.bot = Some(bot);
        self
    }

    /// Load a BASIC script
    pub fn load_script(&mut self, name: &str, content: &str) -> &mut Self {
        self.script_cache
            .lock()
            .unwrap()
            .insert(name.to_string(), content.to_string());
        self
    }

    /// Load a script from a file
    pub fn load_script_file(&mut self, name: &str, path: &PathBuf) -> Result<&mut Self> {
        let content = std::fs::read_to_string(path)
            .with_context(|| format!("Failed to read script file: {:?}", path))?;
        self.script_cache
            .lock()
            .unwrap()
            .insert(name.to_string(), content);
        Ok(self)
    }

    /// Start a new session
    pub fn start_session(&mut self, customer: Customer) -> Result<Uuid> {
        let session_id = Uuid::new_v4();
        let bot_id = self.bot.as_ref().map(|b| b.id).unwrap_or_else(Uuid::new_v4);

        let session = Session {
            id: session_id,
            bot_id,
            customer_id: customer.id,
            channel: customer.channel,
            ..Default::default()
        };

        let state = SessionState {
            session,
            channel: customer.channel,
            customer,
            context: HashMap::new(),
            conversation_state: ConversationState::Initial,
            message_count: 0,
            started_at: Instant::now(),
        };

        self.sessions.lock().unwrap().insert(session_id, state);

        Ok(session_id)
    }

    /// End a session
    pub fn end_session(&mut self, session_id: Uuid) -> Result<()> {
        self.sessions.lock().unwrap().remove(&session_id);
        Ok(())
    }

    /// Process a message in a session
    pub async fn process_message(
        &mut self,
        session_id: Uuid,
        message: &str,
    ) -> Result<ExecutionResult> {
        let start = Instant::now();
        let mut logs = Vec::new();

        // Update metrics
        {
            let mut metrics = self.metrics.lock().unwrap();
            metrics.total_requests += 1;
        }

        // Get session state
        let state = {
            let sessions = self.sessions.lock().unwrap();
            sessions.get(&session_id).cloned()
        };

        let state = match state {
            Some(s) => s,
            None => {
                return Ok(ExecutionResult {
                    session_id,
                    response: None,
                    state: ConversationState::Error,
                    execution_time: start.elapsed(),
                    logs,
                    error: Some("Session not found".to_string()),
                });
            }
        };

        if self.config.capture_logs {
            logs.push(LogEntry {
                timestamp: chrono::Utc::now(),
                level: LogLevel::Debug,
                message: format!("Processing message: {}", message),
                context: HashMap::new(),
            });
        }

        // Execute bot logic (placeholder - would call actual bot runtime)
        let response = self.execute_bot_logic(session_id, message, &state).await;

        let execution_time = start.elapsed();

        // Update metrics
        {
            let mut metrics = self.metrics.lock().unwrap();
            let latency_ms = execution_time.as_millis() as u64;
            metrics.total_latency_ms += latency_ms;

            if metrics.min_latency_ms == 0 || latency_ms < metrics.min_latency_ms {
                metrics.min_latency_ms = latency_ms;
            }
            if latency_ms > metrics.max_latency_ms {
                metrics.max_latency_ms = latency_ms;
            }

            if response.is_ok() {
                metrics.successful_requests += 1;
            } else {
                metrics.failed_requests += 1;
            }
        }

        // Update session state
        {
            let mut sessions = self.sessions.lock().unwrap();
            if let Some(session_state) = sessions.get_mut(&session_id) {
                session_state.message_count += 1;
                session_state.conversation_state = ConversationState::WaitingForUser;
            }
        }

        match response {
            Ok(bot_response) => Ok(ExecutionResult {
                session_id,
                response: Some(bot_response),
                state: ConversationState::WaitingForUser,
                execution_time,
                logs,
                error: None,
            }),
            Err(e) => Ok(ExecutionResult {
                session_id,
                response: None,
                state: ConversationState::Error,
                execution_time,
                logs,
                error: Some(e.to_string()),
            }),
        }
    }

    /// Execute bot logic (placeholder for actual implementation)
    async fn execute_bot_logic(
        &self,
        _session_id: Uuid,
        message: &str,
        _state: &SessionState,
    ) -> Result<BotResponse> {
        // In a real implementation, this would:
        // 1. Load the bot's BASIC script
        // 2. Execute it with the message as input
        // 3. Return the bot's response

        // For now, return a mock response
        Ok(BotResponse {
            id: Uuid::new_v4(),
            content: format!("Echo: {}", message),
            content_type: ResponseContentType::Text,
            metadata: HashMap::new(),
            latency_ms: 50,
        })
    }

    /// Execute a BASIC script directly
    pub async fn execute_script(
        &mut self,
        script_name: &str,
        input: &str,
    ) -> Result<ExecutionResult> {
        let session_id = Uuid::new_v4();
        let start = Instant::now();
        let mut logs = Vec::new();

        // Get script from cache
        let script = {
            let cache = self.script_cache.lock().unwrap();
            cache.get(script_name).cloned()
        };

        let script = match script {
            Some(s) => s,
            None => {
                return Ok(ExecutionResult {
                    session_id,
                    response: None,
                    state: ConversationState::Error,
                    execution_time: start.elapsed(),
                    logs,
                    error: Some(format!("Script '{}' not found", script_name)),
                });
            }
        };

        if self.config.capture_logs {
            logs.push(LogEntry {
                timestamp: chrono::Utc::now(),
                level: LogLevel::Debug,
                message: format!("Executing script: {}", script_name),
                context: HashMap::new(),
            });
        }

        // Update metrics
        {
            let mut metrics = self.metrics.lock().unwrap();
            metrics.script_executions += 1;
        }

        // Execute script (placeholder)
        let result = self.execute_script_internal(&script, input).await;

        let execution_time = start.elapsed();

        match result {
            Ok(output) => Ok(ExecutionResult {
                session_id,
                response: Some(BotResponse {
                    id: Uuid::new_v4(),
                    content: output,
                    content_type: ResponseContentType::Text,
                    metadata: HashMap::new(),
                    latency_ms: execution_time.as_millis() as u64,
                }),
                state: ConversationState::WaitingForUser,
                execution_time,
                logs,
                error: None,
            }),
            Err(e) => Ok(ExecutionResult {
                session_id,
                response: None,
                state: ConversationState::Error,
                execution_time,
                logs,
                error: Some(e.to_string()),
            }),
        }
    }

    /// Internal script execution (placeholder)
    async fn execute_script_internal(&self, _script: &str, input: &str) -> Result<String> {
        // In a real implementation, this would parse and execute the BASIC script
        // For now, just echo the input
        Ok(format!("Script output for: {}", input))
    }

    /// Get current metrics
    pub fn metrics(&self) -> RunnerMetrics {
        self.metrics.lock().unwrap().clone()
    }

    /// Reset metrics
    pub fn reset_metrics(&mut self) {
        *self.metrics.lock().unwrap() = RunnerMetrics::default();
    }

    /// Get active session count
    pub fn active_session_count(&self) -> usize {
        self.sessions.lock().unwrap().len()
    }

    /// Get session info
    pub fn get_session_info(&self, session_id: Uuid) -> Option<SessionInfo> {
        let sessions = self.sessions.lock().unwrap();
        sessions.get(&session_id).map(|s| SessionInfo {
            session_id: s.session.id,
            customer_id: s.customer.id,
            channel: s.channel,
            message_count: s.message_count,
            state: s.conversation_state,
            duration: s.started_at.elapsed(),
        })
    }

    /// Set environment variable for bot execution
    pub fn set_env(&mut self, key: &str, value: &str) -> &mut Self {
        self.config
            .env_vars
            .insert(key.to_string(), value.to_string());
        self
    }

    /// Set timeout
    pub fn set_timeout(&mut self, timeout: Duration) -> &mut Self {
        self.config.timeout = timeout;
        self
    }
}

impl Default for BotRunner {
    fn default() -> Self {
        Self::new()
    }
}

/// Information about a session
#[derive(Debug, Clone)]
pub struct SessionInfo {
    pub session_id: Uuid,
    pub customer_id: Uuid,
    pub channel: Channel,
    pub message_count: usize,
    pub state: ConversationState,
    pub duration: Duration,
}

// Implement Clone for SessionState
impl Clone for SessionState {
    fn clone(&self) -> Self {
        Self {
            session: self.session.clone(),
            customer: self.customer.clone(),
            channel: self.channel,
            context: self.context.clone(),
            conversation_state: self.conversation_state,
            message_count: self.message_count,
            started_at: self.started_at,
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_bot_runner_config_default() {
        let config = BotRunnerConfig::default();
        assert_eq!(config.timeout, Duration::from_secs(30));
        assert!(config.use_mocks);
        assert!(config.capture_logs);
    }

    #[test]
    fn test_runner_metrics_avg_latency() {
        let mut metrics = RunnerMetrics::default();
        metrics.total_requests = 10;
        metrics.total_latency_ms = 1000;

        assert_eq!(metrics.avg_latency_ms(), 100);
    }

    #[test]
    fn test_runner_metrics_success_rate() {
        let mut metrics = RunnerMetrics::default();
        metrics.total_requests = 100;
        metrics.successful_requests = 95;

        assert_eq!(metrics.success_rate(), 95.0);
    }

    #[test]
    fn test_runner_metrics_zero_requests() {
        let metrics = RunnerMetrics::default();
        assert_eq!(metrics.avg_latency_ms(), 0);
        assert_eq!(metrics.success_rate(), 0.0);
    }

    #[test]
    fn test_bot_runner_new() {
        let runner = BotRunner::new();
        assert_eq!(runner.active_session_count(), 0);
    }

    #[test]
    fn test_load_script() {
        let mut runner = BotRunner::new();
        runner.load_script("test", "TALK \"Hello\"");

        let cache = runner.script_cache.lock().unwrap();
        assert!(cache.contains_key("test"));
    }

    #[test]
    fn test_start_session() {
        let mut runner = BotRunner::new();
        let customer = Customer::default();

        let session_id = runner.start_session(customer).unwrap();

        assert_eq!(runner.active_session_count(), 1);
        assert!(runner.get_session_info(session_id).is_some());
    }

    #[test]
    fn test_end_session() {
        let mut runner = BotRunner::new();
        let customer = Customer::default();

        let session_id = runner.start_session(customer).unwrap();
        assert_eq!(runner.active_session_count(), 1);

        runner.end_session(session_id).unwrap();
        assert_eq!(runner.active_session_count(), 0);
    }

    #[tokio::test]
    async fn test_process_message() {
        let mut runner = BotRunner::new();
        let customer = Customer::default();

        let session_id = runner.start_session(customer).unwrap();
        let result = runner.process_message(session_id, "Hello").await.unwrap();

        assert!(result.response.is_some());
        assert!(result.error.is_none());
        assert_eq!(result.state, ConversationState::WaitingForUser);
    }

    #[tokio::test]
    async fn test_process_message_invalid_session() {
        let mut runner = BotRunner::new();
        let invalid_session_id = Uuid::new_v4();

        let result = runner
            .process_message(invalid_session_id, "Hello")
            .await
            .unwrap();

        assert!(result.response.is_none());
        assert!(result.error.is_some());
        assert_eq!(result.state, ConversationState::Error);
    }

    #[tokio::test]
    async fn test_execute_script() {
        let mut runner = BotRunner::new();
        runner.load_script("greeting", "TALK \"Hello\"");

        let result = runner.execute_script("greeting", "Hi").await.unwrap();

        assert!(result.response.is_some());
        assert!(result.error.is_none());
    }

    #[tokio::test]
    async fn test_execute_script_not_found() {
        let mut runner = BotRunner::new();

        let result = runner.execute_script("nonexistent", "Hi").await.unwrap();

        assert!(result.response.is_none());
        assert!(result.error.is_some());
        assert!(result.error.unwrap().contains("not found"));
    }

    #[test]
    fn test_metrics_tracking() {
        let runner = BotRunner::new();
        let metrics = runner.metrics();

        assert_eq!(metrics.total_requests, 0);
        assert_eq!(metrics.successful_requests, 0);
    }

    #[test]
    fn test_reset_metrics() {
        let mut runner = BotRunner::new();

        // Manually update metrics
        {
            let mut metrics = runner.metrics.lock().unwrap();
            metrics.total_requests = 100;
        }

        runner.reset_metrics();
        let metrics = runner.metrics();

        assert_eq!(metrics.total_requests, 0);
    }

    #[test]
    fn test_set_env() {
        let mut runner = BotRunner::new();
        runner.set_env("API_KEY", "test123");

        assert_eq!(
            runner.config.env_vars.get("API_KEY"),
            Some(&"test123".to_string())
        );
    }

    #[test]
    fn test_set_timeout() {
        let mut runner = BotRunner::new();
        runner.set_timeout(Duration::from_secs(60));

        assert_eq!(runner.config.timeout, Duration::from_secs(60));
    }

    #[test]
    fn test_session_info() {
        let mut runner = BotRunner::new();
        let customer = Customer::default();
        let customer_id = customer.id;

        let session_id = runner.start_session(customer).unwrap();
        let info = runner.get_session_info(session_id).unwrap();

        assert_eq!(info.session_id, session_id);
        assert_eq!(info.customer_id, customer_id);
        assert_eq!(info.message_count, 0);
        assert_eq!(info.state, ConversationState::Initial);
    }

    #[test]
    fn test_log_level_default() {
        let level = LogLevel::default();
        assert_eq!(level, LogLevel::Info);
    }
}