//! Field indexing for SQL predicate evaluation.
//!
//! Indexes specified fields for 10-50x speedup on WHERE clauses.

use crate::types::Result;
use crate::storage::Storage;
use uuid::Uuid;

/// Field indexer for fast SQL predicates.
pub struct FieldIndexer {
    storage: Storage,
}

impl FieldIndexer {
    /// Create new field indexer.
    ///
    /// # Arguments
    ///
    /// * `storage` - Storage instance
    ///
    /// # Returns
    ///
    /// New `FieldIndexer`
    pub fn new(storage: Storage) -> Self {
        todo!("Implement FieldIndexer::new")
    }

    /// Index field value for entity.
    ///
    /// # Arguments
    ///
    /// * `tenant_id` - Tenant scope
    /// * `field_name` - Field name
    /// * `field_value` - Field value
    /// * `entity_id` - Entity UUID
    ///
    /// # Errors
    ///
    /// Returns `DatabaseError::StorageError` if indexing fails
    pub fn index_field(
        &self,
        tenant_id: &str,
        field_name: &str,
        field_value: &str,
        entity_id: Uuid,
    ) -> Result<()> {
        todo!("Implement FieldIndexer::index_field")
    }

    /// Lookup entities by field value.
    ///
    /// # Arguments
    ///
    /// * `tenant_id` - Tenant scope
    /// * `field_name` - Field name
    /// * `field_value` - Field value
    ///
    /// # Returns
    ///
    /// Vector of entity UUIDs
    ///
    /// # Errors
    ///
    /// Returns `DatabaseError::StorageError` if lookup fails
    pub fn lookup(
        &self,
        tenant_id: &str,
        field_name: &str,
        field_value: &str,
    ) -> Result<Vec<Uuid>> {
        todo!("Implement FieldIndexer::lookup")
    }

    /// Remove field index for entity.
    ///
    /// # Arguments
    ///
    /// * `tenant_id` - Tenant scope
    /// * `field_name` - Field name
    /// * `field_value` - Field value
    /// * `entity_id` - Entity UUID
    ///
    /// # Errors
    ///
    /// Returns `DatabaseError::StorageError` if removal fails
    pub fn remove_index(
        &self,
        tenant_id: &str,
        field_name: &str,
        field_value: &str,
        entity_id: Uuid,
    ) -> Result<()> {
        todo!("Implement FieldIndexer::remove_index")
    }
}
