foxhunt/risk-data/src/limits.rs

//! Position Limits Repository
//!
//! Manages position limits tracking, enforcement, and breach detection for
//! high-frequency trading systems with real-time monitoring capabilities.

use async_trait::async_trait;
use chrono::{DateTime, Utc};
use redis::aio::ConnectionManager;
use serde::{Deserialize, Serialize};
use sqlx::{PgPool, Row};
use std::collections::HashMap;
use tracing::{error, info, warn};
use rust_decimal::Decimal;
use uuid::Uuid;

use crate::{RiskDataError, RiskDataResult};

/// Position limit types
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, sqlx::Type)]
#[sqlx(type_name = "limit_type", rename_all = "snake_case")]
pub enum LimitType {
    MaxPosition,        // Maximum position size
    MaxDailyVolume,     // Maximum daily trading volume
    MaxDailyLoss,       // Maximum daily loss
    MaxDrawdown,        // Maximum drawdown
    VarLimit,           // VaR-based limit
    ConcentrationLimit, // Portfolio concentration limit
    LeverageLimit,      // Maximum leverage
    ExposureLimit,      // Market exposure limit
}

/// Limit scope (what the limit applies to)
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, sqlx::Type)]
#[sqlx(type_name = "limit_scope", rename_all = "snake_case")]
pub enum LimitScope {
    Global,     // System-wide limit
    Portfolio,  // Portfolio-specific limit
    Strategy,   // Strategy-specific limit
    Symbol,     // Symbol-specific limit
    Sector,     // Sector-specific limit
    AssetClass, // Asset class specific limit
    Trader,     // Trader-specific limit
}

/// Limit breach severity
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, sqlx::Type)]
#[sqlx(type_name = "breach_severity", rename_all = "snake_case")]
pub enum BreachSeverity {
    Warning,  // Approaching limit (80-90%)
    Soft,     // Soft breach (90-100%)
    Hard,     // Hard breach (>100%)
    Critical, // Critical breach (>120%)
}

/// Position limit definition
#[derive(Debug, Clone, Serialize, Deserialize, sqlx::FromRow)]
pub struct PositionLimit {
    pub id: Uuid,
    pub name: String,
    pub limit_type: LimitType,
    pub scope: LimitScope,
    pub scope_value: Option<String>, // Portfolio ID, symbol, etc.
    pub threshold: Decimal,
    pub warning_threshold: Option<Decimal>, // Optional warning level
    pub currency: String,
    pub enabled: bool,
    pub created_at: DateTime<Utc>,
    pub updated_at: DateTime<Utc>,
    pub created_by: String,
    pub description: Option<String>,
    pub metadata: serde_json::Value,
}

/// Current position exposure
#[derive(Debug, Clone, Serialize, Deserialize, sqlx::FromRow)]
pub struct PositionExposure {
    pub scope: LimitScope,
    pub scope_value: String,
    pub symbol: Option<String>,
    pub current_position: Decimal,
    pub current_value: Decimal,
    pub daily_volume: Decimal,
    pub daily_pnl: Decimal,
    pub currency: String,
    pub updated_at: DateTime<Utc>,
}

/// Limit breach event
#[derive(Debug, Clone, Serialize, Deserialize, sqlx::FromRow)]
pub struct LimitBreach {
    pub id: Uuid,
    pub limit_id: Uuid,
    pub severity: BreachSeverity,
    pub breach_time: DateTime<Utc>,
    pub current_value: Decimal,
    pub limit_threshold: Decimal,
    pub breach_percentage: Decimal,
    pub scope: LimitScope,
    pub scope_value: Option<String>,
    pub symbol: Option<String>,
    pub portfolio_id: Option<String>,
    pub strategy_id: Option<String>,
    pub trader_id: Option<String>,
    pub acknowledged: bool,
    pub acknowledged_by: Option<String>,
    pub acknowledged_at: Option<DateTime<Utc>>,
    pub resolved: bool,
    pub resolved_at: Option<DateTime<Utc>>,
    pub resolution_note: Option<String>,
    pub action_taken: Option<String>,
}

/// Limit check request
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct LimitCheckRequest {
    pub scope: LimitScope,
    pub scope_value: String,
    pub symbol: Option<String>,
    pub proposed_position: Decimal,
    pub proposed_value: Decimal,
    pub currency: String,
}

/// Limit check result
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct LimitCheckResult {
    pub allowed: bool,
    pub violations: Vec<LimitViolation>,
    pub warnings: Vec<LimitViolation>,
    pub max_allowed_position: Option<Decimal>,
    pub max_allowed_value: Option<Decimal>,
}

/// Individual limit violation
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct LimitViolation {
    pub limit_id: Uuid,
    pub limit_name: String,
    pub limit_type: LimitType,
    pub current_value: Decimal,
    pub limit_threshold: Decimal,
    pub breach_percentage: Decimal,
    pub severity: BreachSeverity,
}

/// Limits repository trait
#[async_trait]
pub trait LimitsRepository: Send + Sync + std::fmt::Debug {
    /// Create or update a position limit
    async fn upsert_limit(&self, limit: PositionLimit) -> RiskDataResult<()>;

    /// Get all limits for a scope
    async fn get_limits(
        &self,
        scope: LimitScope,
        scope_value: Option<String>,
    ) -> RiskDataResult<Vec<PositionLimit>>;

    /// Get a specific limit by ID
    async fn get_limit(&self, limit_id: Uuid) -> RiskDataResult<Option<PositionLimit>>;

    /// Delete a limit
    async fn delete_limit(&self, limit_id: Uuid) -> RiskDataResult<()>;

    /// Update position exposure
    async fn update_exposure(&self, exposure: PositionExposure) -> RiskDataResult<()>;

    /// Get current exposure for a scope
    async fn get_exposure(
        &self,
        scope: LimitScope,
        scope_value: &str,
    ) -> RiskDataResult<Option<PositionExposure>>;

    /// Check if a proposed position would violate limits
    async fn check_limits(&self, request: LimitCheckRequest) -> RiskDataResult<LimitCheckResult>;

    /// Record a limit breach
    async fn record_breach(&self, breach: LimitBreach) -> RiskDataResult<()>;

    /// Get recent breaches
    async fn get_breaches(
        &self,
        from: DateTime<Utc>,
        to: DateTime<Utc>,
        severity: Option<BreachSeverity>,
    ) -> RiskDataResult<Vec<LimitBreach>>;

    /// Acknowledge a breach
    async fn acknowledge_breach(
        &self,
        breach_id: Uuid,
        acknowledged_by: String,
    ) -> RiskDataResult<()>;

    /// Resolve a breach
    async fn resolve_breach(
        &self,
        breach_id: Uuid,
        resolution_note: String,
        action_taken: String,
    ) -> RiskDataResult<()>;

    /// Get limit utilization summary
    async fn get_utilization_summary(&self) -> RiskDataResult<HashMap<String, Decimal>>;

    /// Perform real-time limit monitoring
    async fn monitor_limits(&self) -> RiskDataResult<Vec<LimitBreach>>;
}

/// Limits repository implementation
#[derive(Clone)]
pub struct LimitsRepositoryImpl {
    db_pool: PgPool,
    redis_conn: ConnectionManager,
}

impl std::fmt::Debug for LimitsRepositoryImpl {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("LimitsRepositoryImpl")
            .field("db_pool", &"<PgPool>")
            .field("redis_conn", &"<ConnectionManager>")
            .finish()
    }
}

impl LimitsRepositoryImpl {
    pub const fn new(db_pool: PgPool, redis_conn: ConnectionManager) -> Self {
        Self {
            db_pool,
            redis_conn,
        }
    }

    /// Validate limit configuration
    fn validate_limit(&self, limit: &PositionLimit) -> RiskDataResult<()> {
        if limit.name.is_empty() {
            return Err(RiskDataError::LimitsValidation(
                "Limit name cannot be empty".to_owned(),
            ));
        }

        if limit.threshold <= Decimal::ZERO {
            return Err(RiskDataError::LimitsValidation(
                "Limit threshold must be positive".to_owned(),
            ));
        }

        // Validate warning threshold if provided
        if let Some(warning) = limit.warning_threshold {
            if warning <= Decimal::ZERO || warning >= limit.threshold {
                return Err(RiskDataError::LimitsValidation(
                    "Warning threshold must be positive and less than limit threshold".to_owned(),
                ));
            }
        }

        // Validate scope-specific requirements
        match limit.scope {
            LimitScope::Portfolio
            | LimitScope::Strategy
            | LimitScope::Symbol
            | LimitScope::Sector
            | LimitScope::AssetClass
            | LimitScope::Trader => {
                if limit.scope_value.is_none() || limit.scope_value.as_ref().unwrap().is_empty() {
                    return Err(RiskDataError::LimitsValidation(format!(
                        "Scope value required for {:?} limits",
                        limit.scope
                    )));
                }
            }
            LimitScope::Global => {
                // Global limits don't require scope_value
            }
        }

        Ok(())
    }

    /// Calculate breach severity based on percentage
    fn calculate_breach_severity(&self, breach_percentage: Decimal) -> BreachSeverity {
        if breach_percentage >= Decimal::from(120) {
            BreachSeverity::Critical
        } else if breach_percentage >= Decimal::from(100) {
            BreachSeverity::Hard
        } else if breach_percentage >= Decimal::from(90) {
            BreachSeverity::Soft
        } else {
            BreachSeverity::Warning
        }
    }

    /// Check a single limit against current exposure
    async fn check_single_limit(
        &self,
        limit: &PositionLimit,
        current_exposure: &PositionExposure,
        proposed_value: Decimal,
    ) -> RiskDataResult<Option<LimitViolation>> {
        if !limit.enabled {
            return Ok(None);
        }

        let test_value = match limit.limit_type {
            LimitType::MaxPosition => current_exposure.current_position + proposed_value,
            LimitType::MaxDailyVolume => current_exposure.daily_volume + proposed_value.abs(),
            LimitType::MaxDailyLoss => {
                if current_exposure.daily_pnl < Decimal::ZERO {
                    current_exposure.daily_pnl.abs() // Current loss
                } else {
                    Decimal::ZERO
                }
            }
            LimitType::ExposureLimit => current_exposure.current_value + proposed_value,
            _ => current_exposure.current_value, // Simplified for other types
        };

        let breach_percentage = (test_value / limit.threshold) * Decimal::from(100);

        // Check for breach or warning
        let threshold_to_check = if let Some(warning) = limit.warning_threshold {
            if breach_percentage >= (warning / limit.threshold) * Decimal::from(100) {
                warning
            } else {
                return Ok(None); // No violation
            }
        } else {
            limit.threshold
        };

        if test_value > threshold_to_check {
            let severity = if test_value > limit.threshold {
                self.calculate_breach_severity(breach_percentage)
            } else {
                BreachSeverity::Warning
            };

            Ok(Some(LimitViolation {
                limit_id: limit.id,
                limit_name: limit.name.clone(),
                limit_type: limit.limit_type,
                current_value: test_value,
                limit_threshold: limit.threshold,
                breach_percentage,
                severity,
            }))
        } else {
            Ok(None)
        }
    }
}

#[async_trait]
impl LimitsRepository for LimitsRepositoryImpl {
    async fn upsert_limit(&self, limit: PositionLimit) -> RiskDataResult<()> {
        self.validate_limit(&limit)?;

        let query = "
            INSERT INTO position_limits (
                id, name, limit_type, scope, scope_value, threshold, warning_threshold,
                currency, enabled, created_at, updated_at, created_by, description, metadata
            ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14)
            ON CONFLICT (id) DO UPDATE SET
                name = EXCLUDED.name,
                threshold = EXCLUDED.threshold,
                warning_threshold = EXCLUDED.warning_threshold,
                enabled = EXCLUDED.enabled,
                updated_at = EXCLUDED.updated_at,
                description = EXCLUDED.description,
                metadata = EXCLUDED.metadata
        ";

        sqlx::query(query)
            .bind(limit.id)
            .bind(&limit.name)
            .bind(limit.limit_type)
            .bind(limit.scope)
            .bind(&limit.scope_value)
            .bind(limit.threshold)
            .bind(limit.warning_threshold)
            .bind(&limit.currency)
            .bind(limit.enabled)
            .bind(limit.created_at)
            .bind(limit.updated_at)
            .bind(&limit.created_by)
            .bind(&limit.description)
            .bind(&limit.metadata)
            .execute(&self.db_pool)
            .await?;

        // Cache active limits in Redis for fast access
        if limit.enabled {
            let cache_key = format!(
                "limits:{}:{}",
                limit.scope as u8,
                limit.scope_value.as_deref().unwrap_or("global")
            );
            let serialized = serde_json::to_string(&limit)?;

            let mut redis_conn = self.redis_conn.clone();
            redis::cmd("HSET")
                .arg(&cache_key)
                .arg(limit.id.to_string())
                .arg(&serialized)
                .query_async::<()>(&mut redis_conn)
                .await?;
        }

        info!(
            "Position limit upserted: {} - {}",
            limit.name, limit.threshold
        );
        Ok(())
    }

    async fn get_limits(
        &self,
        scope: LimitScope,
        scope_value: Option<String>,
    ) -> RiskDataResult<Vec<PositionLimit>> {
        let query = if scope_value.is_some() {
            "SELECT * FROM position_limits WHERE scope = $1 AND scope_value = $2 ORDER BY name"
        } else {
            "SELECT * FROM position_limits WHERE scope = $1 AND scope_value IS NULL ORDER BY name"
        };

        let limits = if let Some(sv) = scope_value {
            sqlx::query_as::<_, PositionLimit>(query)
                .bind(scope)
                .bind(sv)
                .fetch_all(&self.db_pool)
                .await?
        } else {
            sqlx::query_as::<_, PositionLimit>(query)
                .bind(scope)
                .fetch_all(&self.db_pool)
                .await?
        };

        Ok(limits)
    }

    async fn get_limit(&self, limit_id: Uuid) -> RiskDataResult<Option<PositionLimit>> {
        let query = "SELECT * FROM position_limits WHERE id = $1";

        let limit = sqlx::query_as::<_, PositionLimit>(query)
            .bind(limit_id)
            .fetch_optional(&self.db_pool)
            .await?;

        Ok(limit)
    }

    async fn delete_limit(&self, limit_id: Uuid) -> RiskDataResult<()> {
        // Remove from database
        let query = "DELETE FROM position_limits WHERE id = $1";
        sqlx::query(query)
            .bind(limit_id)
            .execute(&self.db_pool)
            .await?;

        // Remove from Redis cache
        let mut redis_conn = self.redis_conn.clone();
        let cache_keys: Vec<String> = redis::cmd("KEYS")
            .arg("limits:*")
            .query_async(&mut redis_conn)
            .await?;

        for key in cache_keys {
            redis::cmd("HDEL")
                .arg(&key)
                .arg(limit_id.to_string())
                .query_async::<()>(&mut redis_conn)
                .await?;
        }

        info!("Position limit deleted: {}", limit_id);
        Ok(())
    }

    async fn update_exposure(&self, exposure: PositionExposure) -> RiskDataResult<()> {
        let query = "
            INSERT INTO position_exposures (
                scope, scope_value, symbol, current_position, current_value,
                daily_volume, daily_pnl, currency, updated_at
            ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9)
            ON CONFLICT (scope, scope_value, COALESCE(symbol, '')) DO UPDATE SET
                current_position = EXCLUDED.current_position,
                current_value = EXCLUDED.current_value,
                daily_volume = EXCLUDED.daily_volume,
                daily_pnl = EXCLUDED.daily_pnl,
                updated_at = EXCLUDED.updated_at
        ";

        sqlx::query(query)
            .bind(exposure.scope)
            .bind(&exposure.scope_value)
            .bind(&exposure.symbol)
            .bind(exposure.current_position)
            .bind(exposure.current_value)
            .bind(exposure.daily_volume)
            .bind(exposure.daily_pnl)
            .bind(&exposure.currency)
            .bind(exposure.updated_at)
            .execute(&self.db_pool)
            .await?;

        // Cache current exposure in Redis for real-time access
        let cache_key = format!("exposure:{}:{}", exposure.scope as u8, exposure.scope_value);
        let serialized = serde_json::to_string(&exposure)?;

        let mut redis_conn = self.redis_conn.clone();
        redis::cmd("SETEX")
            .arg(&cache_key)
            .arg(300) // 5 minutes TTL
            .arg(&serialized)
            .query_async::<()>(&mut redis_conn)
            .await?;

        Ok(())
    }

    async fn get_exposure(
        &self,
        scope: LimitScope,
        scope_value: &str,
    ) -> RiskDataResult<Option<PositionExposure>> {
        // Try Redis cache first
        let cache_key = format!("exposure:{}:{}", scope as u8, scope_value);
        let mut redis_conn = self.redis_conn.clone();

        if let Ok(cached) = redis::cmd("GET")
            .arg(&cache_key)
            .query_async::<String>(&mut redis_conn)
            .await
        {
            if let Ok(exposure) = serde_json::from_str::<PositionExposure>(&cached) {
                return Ok(Some(exposure));
            }
        }

        // Fallback to database
        let query = "SELECT * FROM position_exposures WHERE scope = $1 AND scope_value = $2";

        let exposure = sqlx::query_as::<_, PositionExposure>(query)
            .bind(scope)
            .bind(scope_value)
            .fetch_optional(&self.db_pool)
            .await?;

        Ok(exposure)
    }

    async fn check_limits(&self, request: LimitCheckRequest) -> RiskDataResult<LimitCheckResult> {
        // Get applicable limits
        let mut all_limits = Vec::new();

        // Global limits
        all_limits.extend(self.get_limits(LimitScope::Global, None).await?);

        // Scope-specific limits
        all_limits.extend(
            self.get_limits(request.scope, Some(request.scope_value.clone()))
                .await?,
        );

        // Symbol-specific limits if symbol provided
        if let Some(symbol) = &request.symbol {
            all_limits.extend(
                self.get_limits(LimitScope::Symbol, Some(symbol.clone()))
                    .await?,
            );
        }

        // Get current exposure
        let current_exposure = self
            .get_exposure(request.scope, &request.scope_value)
            .await?
            .unwrap_or_else(|| PositionExposure {
                scope: request.scope,
                scope_value: request.scope_value.clone(),
                symbol: request.symbol.clone(),
                current_position: Decimal::ZERO,
                current_value: Decimal::ZERO,
                daily_volume: Decimal::ZERO,
                daily_pnl: Decimal::ZERO,
                currency: request.currency.clone(),
                updated_at: Utc::now(),
            });

        let mut violations = Vec::new();
        let mut warnings = Vec::new();

        // Check each limit
        for limit in &all_limits {
            if let Some(violation) = self
                .check_single_limit(limit, &current_exposure, request.proposed_value)
                .await?
            {
                match violation.severity {
                    BreachSeverity::Warning => warnings.push(violation),
                    _ => violations.push(violation),
                }
            }
        }

        let allowed = violations.is_empty();

        // Calculate max allowed position/value if there are violations
        let (max_allowed_position, max_allowed_value) = if !allowed {
            // Find the most restrictive limit
            let min_limit = all_limits
                .iter()
                .filter(|l| l.enabled)
                .map(|l| l.threshold)
                .min()
                .unwrap_or(Decimal::ZERO);

            let max_pos = min_limit - current_exposure.current_position;
            let max_val = min_limit - current_exposure.current_value;

            (
                Some(max_pos.max(Decimal::ZERO)),
                Some(max_val.max(Decimal::ZERO)),
            )
        } else {
            (None, None)
        };

        Ok(LimitCheckResult {
            allowed,
            violations,
            warnings,
            max_allowed_position,
            max_allowed_value,
        })
    }

    async fn record_breach(&self, breach: LimitBreach) -> RiskDataResult<()> {
        let query = "
            INSERT INTO limit_breaches (
                id, limit_id, severity, breach_time, current_value, limit_threshold,
                breach_percentage, scope, scope_value, symbol, portfolio_id, strategy_id,
                trader_id, acknowledged, acknowledged_by, acknowledged_at, resolved,
                resolved_at, resolution_note, action_taken
            ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18, $19, $20)
        ";

        sqlx::query(query)
            .bind(breach.id)
            .bind(breach.limit_id)
            .bind(breach.severity)
            .bind(breach.breach_time)
            .bind(breach.current_value)
            .bind(breach.limit_threshold)
            .bind(breach.breach_percentage)
            .bind(breach.scope)
            .bind(&breach.scope_value)
            .bind(&breach.symbol)
            .bind(&breach.portfolio_id)
            .bind(&breach.strategy_id)
            .bind(&breach.trader_id)
            .bind(breach.acknowledged)
            .bind(&breach.acknowledged_by)
            .bind(breach.acknowledged_at)
            .bind(breach.resolved)
            .bind(breach.resolved_at)
            .bind(&breach.resolution_note)
            .bind(&breach.action_taken)
            .execute(&self.db_pool)
            .await?;

        // Cache critical breaches for immediate alerting
        if matches!(
            breach.severity,
            BreachSeverity::Critical | BreachSeverity::Hard
        ) {
            let cache_key = format!("breach:critical:{}", breach.id);
            let serialized = serde_json::to_string(&breach)?;

            let mut redis_conn = self.redis_conn.clone();
            redis::cmd("SETEX")
                .arg(&cache_key)
                .arg(7200) // 2 hours TTL
                .arg(&serialized)
                .query_async::<()>(&mut redis_conn)
                .await?;
        }

        error!(
            "Limit breach recorded: {:?} - {} exceeds {} by {}%",
            breach.severity, breach.current_value, breach.limit_threshold, breach.breach_percentage
        );

        Ok(())
    }

    async fn get_breaches(
        &self,
        from: DateTime<Utc>,
        to: DateTime<Utc>,
        severity: Option<BreachSeverity>,
    ) -> RiskDataResult<Vec<LimitBreach>> {
        let query = if severity.is_some() {
            "
                SELECT * FROM limit_breaches 
                WHERE breach_time BETWEEN $1 AND $2 AND severity = $3
                ORDER BY breach_time DESC
            "
        } else {
            "
                SELECT * FROM limit_breaches 
                WHERE breach_time BETWEEN $1 AND $2
                ORDER BY breach_time DESC
            "
        };

        let breaches = if let Some(sev) = severity {
            sqlx::query_as::<_, LimitBreach>(query)
                .bind(from)
                .bind(to)
                .bind(sev)
                .fetch_all(&self.db_pool)
                .await?
        } else {
            sqlx::query_as::<_, LimitBreach>(query)
                .bind(from)
                .bind(to)
                .fetch_all(&self.db_pool)
                .await?
        };

        Ok(breaches)
    }

    async fn acknowledge_breach(
        &self,
        breach_id: Uuid,
        acknowledged_by: String,
    ) -> RiskDataResult<()> {
        let query = "
            UPDATE limit_breaches 
            SET acknowledged = true, acknowledged_by = $2, acknowledged_at = $3
            WHERE id = $1
        ";

        sqlx::query(query)
            .bind(breach_id)
            .bind(&acknowledged_by)
            .bind(Utc::now())
            .execute(&self.db_pool)
            .await?;

        info!(
            "Limit breach {} acknowledged by {}",
            breach_id, acknowledged_by
        );
        Ok(())
    }

    async fn resolve_breach(
        &self,
        breach_id: Uuid,
        resolution_note: String,
        action_taken: String,
    ) -> RiskDataResult<()> {
        let query = "
            UPDATE limit_breaches 
            SET resolved = true, resolved_at = $2, resolution_note = $3, action_taken = $4
            WHERE id = $1
        ";

        sqlx::query(query)
            .bind(breach_id)
            .bind(Utc::now())
            .bind(&resolution_note)
            .bind(&action_taken)
            .execute(&self.db_pool)
            .await?;

        info!("Limit breach {} resolved: {}", breach_id, resolution_note);
        Ok(())
    }

    async fn get_utilization_summary(&self) -> RiskDataResult<HashMap<String, Decimal>> {
        let query = "
            SELECT 
                l.name,
                l.threshold,
                COALESCE(e.current_value, 0) as current_value
            FROM position_limits l
            LEFT JOIN position_exposures e ON 
                l.scope = e.scope AND 
                l.scope_value = e.scope_value
            WHERE l.enabled = true
        ";

        let rows = sqlx::query(query).fetch_all(&self.db_pool).await?;

        let mut summary = HashMap::new();

        for row in rows {
            let name: String = row.get("name");
            let threshold: Decimal = row.get("threshold");
            let current: Decimal = row.get("current_value");

            let utilization = if threshold > Decimal::ZERO {
                (current / threshold) * Decimal::from(100)
            } else {
                Decimal::ZERO
            };

            summary.insert(name, utilization);
        }

        Ok(summary)
    }

    async fn monitor_limits(&self) -> RiskDataResult<Vec<LimitBreach>> {
        info!("Starting real-time limit monitoring");

        // Get all enabled limits
        let query = "SELECT * FROM position_limits WHERE enabled = true";
        let limits = sqlx::query_as::<_, PositionLimit>(query)
            .fetch_all(&self.db_pool)
            .await?;

        let mut new_breaches = Vec::new();

        for limit in limits {
            let scope_value = limit.scope_value.as_deref().unwrap_or("global");

            if let Some(exposure) = self.get_exposure(limit.scope, scope_value).await? {
                let test_value = match limit.limit_type {
                    LimitType::MaxPosition => exposure.current_position.abs(),
                    LimitType::MaxDailyVolume => exposure.daily_volume,
                    LimitType::MaxDailyLoss => exposure.daily_pnl.abs(),
                    LimitType::ExposureLimit => exposure.current_value.abs(),
                    _ => exposure.current_value,
                };

                if test_value > limit.threshold {
                    let breach_percentage = (test_value / limit.threshold) * Decimal::from(100);
                    let severity = self.calculate_breach_severity(breach_percentage);

                    let breach = LimitBreach {
                        id: Uuid::new_v4(),
                        limit_id: limit.id,
                        severity,
                        breach_time: Utc::now(),
                        current_value: test_value,
                        limit_threshold: limit.threshold,
                        breach_percentage,
                        scope: limit.scope,
                        scope_value: limit.scope_value.clone(),
                        symbol: exposure.symbol,
                        portfolio_id: None, // Would be derived from scope_value
                        strategy_id: None,
                        trader_id: None,
                        acknowledged: false,
                        acknowledged_by: None,
                        acknowledged_at: None,
                        resolved: false,
                        resolved_at: None,
                        resolution_note: None,
                        action_taken: None,
                    };

                    new_breaches.push(breach);
                }
            }
        }

        // Record any new breaches
        for breach in &new_breaches {
            self.record_breach(breach.clone()).await?;
        }

        if !new_breaches.is_empty() {
            warn!("Detected {} new limit breaches", new_breaches.len());
        }

        Ok(new_breaches)
    }
}

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

    #[test]
    fn test_breach_severity_calculation() {
        let repo = LimitsRepositoryImpl {
            db_pool: PgPool::connect("").unwrap_or_else(|_| panic!("Test DB connection")),
            redis_conn: panic!("Mock Redis connection"),
        };

        assert_eq!(
            repo.calculate_breach_severity(Decimal::from(85)),
            BreachSeverity::Warning
        );
        assert_eq!(
            repo.calculate_breach_severity(Decimal::from(95)),
            BreachSeverity::Soft
        );
        assert_eq!(
            repo.calculate_breach_severity(Decimal::from(105)),
            BreachSeverity::Hard
        );
        assert_eq!(
            repo.calculate_breach_severity(Decimal::from(125)),
            BreachSeverity::Critical
        );
    }

    #[test]
    fn test_limit_validation() {
        let repo = LimitsRepositoryImpl {
            db_pool: PgPool::connect("").unwrap_or_else(|_| panic!("Test DB connection")),
            redis_conn: panic!("Mock Redis connection"),
        };

        let valid_limit = PositionLimit {
            id: Uuid::new_v4(),
            name: "Test Limit".to_string(),
            limit_type: LimitType::MaxPosition,
            scope: LimitScope::Global,
            scope_value: None,
            threshold: Decimal::from(100000),
            warning_threshold: Some(Decimal::from(80000)),
            currency: "USD".to_string(),
            enabled: true,
            created_at: Utc::now(),
            updated_at: Utc::now(),
            created_by: "test_user".to_string(),
            description: Some("Test limit".to_string()),
            metadata: serde_json::json!({}),
        };

        assert!(repo.validate_limit(&valid_limit).is_ok());

        // Test invalid limit (negative threshold)
        let invalid_limit = PositionLimit {
            threshold: Decimal::from(-100),
            ..valid_limit
        };

        assert!(repo.validate_limit(&invalid_limit).is_err());
    }
}