#![allow(
    clippy::unwrap_used,
    clippy::expect_used,
    clippy::indexing_slicing,
    clippy::absurd_extreme_comparisons,
    clippy::field_reassign_with_default,
    clippy::manual_flatten,
    clippy::tests_outside_test_module,
    unused_imports,
    unused_variables,
    unused_comparisons,
    dead_code,
)]
//! Comprehensive test coverage for database module
//! Target: 95%+ coverage for database operations and error handling

use config::database::{DatabaseConfig, PoolConfig, TransactionConfig};
use database::*;

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

    #[test]
    fn test_database_error_types() {
        let connection_error = DatabaseError::Connection {
            message: "Failed to connect".to_string(),
        };
        assert!(connection_error.to_string().contains("Connection failed"));

        let query_error = DatabaseError::Query {
            query: "SELECT *".to_string(),
            message: "Invalid SQL".to_string(),
        };
        assert!(query_error.to_string().contains("Query execution failed"));

        let transaction_error = DatabaseError::Transaction {
            message: "Commit failed".to_string(),
        };
        assert!(transaction_error.to_string().contains("Transaction error"));

        let pool_error = DatabaseError::ConnectionPool {
            message: "Pool exhausted".to_string(),
        };
        assert!(pool_error.to_string().contains("Connection pool error"));
    }

    #[test]
    fn test_database_error_debug() {
        let error = DatabaseError::Connection {
            message: "Test".to_string(),
        };
        let debug_str = format!("{:?}", error);
        assert!(debug_str.contains("Connection"));
    }

    #[test]
    fn test_database_error_retryable() {
        let timeout_error = DatabaseError::Timeout {
            operation: "query".to_string(),
            timeout_secs: 30,
        };
        assert!(timeout_error.is_retryable());

        let validation_error = DatabaseError::Validation {
            field: "email".to_string(),
            message: "invalid format".to_string(),
        };
        assert!(!validation_error.is_retryable());
    }

    #[test]
    fn test_database_error_category() {
        let error = DatabaseError::Configuration {
            message: "Bad config".to_string(),
        };
        assert_eq!(error.category(), "configuration");

        let error = DatabaseError::Migration {
            message: "Migration failed".to_string(),
        };
        assert_eq!(error.category(), "migration");
    }
}

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

    #[test]
    fn test_pool_config_defaults() {
        let config = PoolConfig::default();
        assert!(config.max_connections > 0);
        assert!(config.min_connections > 0);
        assert!(config.max_connections >= config.min_connections);
        assert!(config.health_check_enabled);
    }

    #[test]
    fn test_pool_config_validation() {
        let config = PoolConfig {
            max_connections: 20,
            min_connections: 5,
            acquire_timeout_secs: 30,
            idle_timeout_secs: 600,
            max_lifetime_secs: 1800,
            test_before_acquire: true,
            database_url: "postgresql://localhost/test".to_string(),
            health_check_enabled: true,
            health_check_interval_secs: 60,
        };

        // Validate logical constraints
        assert!(config.max_connections > config.min_connections);
        assert!(config.acquire_timeout_secs > 0);
        assert!(config.idle_timeout_secs > 0);
        assert!(config.max_lifetime_secs > config.idle_timeout_secs);
    }

    #[test]
    fn test_pool_config_serialization() {
        let config = PoolConfig {
            max_connections: 10,
            min_connections: 2,
            acquire_timeout_secs: 15,
            idle_timeout_secs: 300,
            max_lifetime_secs: 900,
            test_before_acquire: false,
            database_url: "postgresql://localhost/test".to_string(),
            health_check_enabled: false,
            health_check_interval_secs: 30,
        };

        let serialized = serde_json::to_string(&config).expect("Serialization failed");
        let deserialized: PoolConfig =
            serde_json::from_str(&serialized).expect("Deserialization failed");
        assert_eq!(config.max_connections, deserialized.max_connections);
        assert_eq!(config.test_before_acquire, deserialized.test_before_acquire);
    }

    #[test]
    fn test_pool_config_edge_cases() {
        // Test minimum possible values
        let min_config = PoolConfig {
            max_connections: 1,
            min_connections: 1,
            acquire_timeout_secs: 1,
            idle_timeout_secs: 1,
            max_lifetime_secs: 1,
            test_before_acquire: false,
            database_url: "postgresql://localhost/test".to_string(),
            health_check_enabled: false,
            health_check_interval_secs: 1,
        };
        assert_eq!(min_config.max_connections, min_config.min_connections);

        // Test large values
        let large_config = PoolConfig {
            max_connections: 1000,
            min_connections: 100,
            acquire_timeout_secs: 3600,
            idle_timeout_secs: 7200,
            max_lifetime_secs: 86400,
            test_before_acquire: true,
            database_url: "postgresql://localhost/test".to_string(),
            health_check_enabled: true,
            health_check_interval_secs: 300,
        };
        assert!(large_config.max_connections > 100);
    }
}

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

    #[test]
    fn test_transaction_config_defaults() {
        let config = TransactionConfig::default();
        assert!(config.max_retries > 0);
        assert!(config.retry_delay_ms > 0);
        assert!(config.enable_retry);
    }

    #[test]
    fn test_transaction_config_validation() {
        let config = TransactionConfig {
            isolation_level: "READ_COMMITTED".to_string(),
            timeout: std::time::Duration::from_secs(30),
            default_timeout_secs: 30,
            enable_retry: true,
            max_retries: 5,
            retry_delay_ms: 100,
            max_savepoints: 10,
        };

        assert!(config.max_retries > 0);
        assert!(config.retry_delay_ms > 0);
        assert!(!config.isolation_level.is_empty());
        assert!(config.enable_retry);
    }

    #[test]
    fn test_transaction_config_serialization() {
        let config = TransactionConfig {
            isolation_level: "SERIALIZABLE".to_string(),
            timeout: std::time::Duration::from_secs(60),
            default_timeout_secs: 60,
            enable_retry: false,
            max_retries: 3,
            retry_delay_ms: 50,
            max_savepoints: 5,
        };

        let serialized = serde_json::to_string(&config).expect("Serialization failed");
        let deserialized: TransactionConfig =
            serde_json::from_str(&serialized).expect("Deserialization failed");
        assert_eq!(config.isolation_level, deserialized.isolation_level);
        assert_eq!(config.enable_retry, deserialized.enable_retry);
    }

    #[test]
    fn test_transaction_isolation_levels() {
        let levels = vec![
            "READ_UNCOMMITTED",
            "READ_COMMITTED",
            "REPEATABLE_READ",
            "SERIALIZABLE",
        ];

        for level in levels {
            let config = TransactionConfig {
                isolation_level: level.to_string(),
                timeout: std::time::Duration::from_secs(30),
                default_timeout_secs: 30,
                enable_retry: true,
                max_retries: 3,
                retry_delay_ms: 100,
                max_savepoints: 10,
            };
            assert_eq!(config.isolation_level, level);
        }
    }
}

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

    #[test]
    fn test_query_builder_basic() {
        let query = Database::select(&["id", "name", "value"])
            .from("test_table")
            .where_raw("active = true")
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("SELECT"));
        assert!(sql.contains("FROM test_table"));
        assert!(sql.contains("WHERE"));
    }

    #[test]
    fn test_query_builder_with_joins() {
        let query = Database::select(&["a.id", "b.name"])
            .from("table_a a")
            .inner_join("table_b b", "a.id = b.a_id")
            .where_raw("a.status = 'active'")
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("INNER JOIN"));
        assert!(sql.contains("a.id = b.a_id"));
    }

    #[test]
    fn test_query_builder_with_order_and_limit() {
        let query = Database::select(&["*"])
            .from("orders")
            .where_raw("amount > 1000")
            .order_by("created_at", OrderDirection::Desc)
            .limit(10)
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("ORDER BY"));
        assert!(sql.contains("LIMIT 10"));
    }

    #[test]
    fn test_insert_builder() {
        let query = Database::insert("users")
            .values(&[("name", "Alice"), ("email", "alice@example.com")])
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("INSERT INTO users"));
    }

    #[test]
    fn test_update_builder() {
        let query = Database::update("users")
            .set("name", "Bob")
            .where_eq("id", 1)
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("UPDATE users"));
        assert!(sql.contains("SET"));
        assert!(sql.contains("WHERE"));
    }

    #[test]
    fn test_delete_builder() {
        let query = Database::delete("users")
            .where_raw("id = 1")
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("DELETE FROM users"));
        assert!(sql.contains("WHERE"));
    }
}

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

    #[test]
    fn test_database_config_new() {
        let config = DatabaseConfig::new();
        assert!(!config.url.is_empty());
        assert!(config.max_connections > 0);
        assert!(config.min_connections > 0);
        assert!(config.max_connections >= config.min_connections);
    }

    #[test]
    fn test_database_config_validation() {
        let mut config = DatabaseConfig::new();
        assert!(config.validate().is_ok());

        config.url = String::new();
        assert!(config.validate().is_err());
    }

    #[test]
    fn test_database_config_serialization() {
        let config = DatabaseConfig::new();
        let serialized = serde_json::to_string(&config).expect("Serialization failed");
        let deserialized: DatabaseConfig =
            serde_json::from_str(&serialized).expect("Deserialization failed");
        assert_eq!(config.url, deserialized.url);
    }

    #[test]
    fn test_database_config_pool_and_transaction() {
        let config = DatabaseConfig::new();
        assert!(config.pool.max_connections > 0);
        assert!(config.transaction.max_retries > 0);
    }
}

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

    #[test]
    fn test_zero_max_connections() {
        let config = PoolConfig {
            max_connections: 0, // Invalid but should handle gracefully
            min_connections: 0,
            acquire_timeout_secs: 30,
            idle_timeout_secs: 600,
            max_lifetime_secs: 1800,
            test_before_acquire: false,
            database_url: "postgresql://localhost/test".to_string(),
            health_check_enabled: false,
            health_check_interval_secs: 60,
        };

        assert_eq!(config.max_connections, 0);
        // Real implementation should validate this
    }

    #[test]
    fn test_negative_timeout() {
        // Using i64 to test negative values
        let timeout = -1;
        assert!(timeout < 0);
        // System should handle negative timeouts (convert to u64 or error)
    }

    #[test]
    fn test_empty_database_url() {
        let mut config = DatabaseConfig::new();
        config.url = String::new();
        assert!(config.url.is_empty());
        // Should be caught by validation
        assert!(config.validate().is_err());
    }

    #[test]
    fn test_constraint_violation_error() {
        let error = DatabaseError::ConstraintViolation {
            constraint: "unique_email".to_string(),
            message: "Email already exists".to_string(),
        };
        assert!(error.to_string().contains("Constraint violation"));
        assert_eq!(error.category(), "constraint_violation");
    }

    #[test]
    fn test_not_found_error() {
        let error = DatabaseError::NotFound {
            resource_type: "User".to_string(),
            identifier: "id=123".to_string(),
        };
        assert!(error.to_string().contains("Resource not found"));
        assert_eq!(error.category(), "not_found");
    }

    #[test]
    fn test_serialization_error() {
        let error = DatabaseError::Serialization {
            message: "Failed to serialize JSON".to_string(),
        };
        assert!(error.to_string().contains("Serialization error"));
        assert_eq!(error.category(), "serialization");
    }
}

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

    #[test]
    fn test_select_with_multiple_where_clauses() {
        let query = Database::select(&["id"])
            .from("products")
            .where_raw("price > 100")
            .where_raw("stock > 0")
            .where_raw("category = 'electronics'")
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("WHERE"));
        // Should combine multiple where clauses
        assert!(sql.contains("price > 100"));
    }

    #[test]
    fn test_insert_returning() {
        let query = Database::insert("users")
            .values(&[("name", "Alice"), ("email", "alice@example.com")])
            .returning("id")
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("RETURNING"));
    }

    #[test]
    fn test_update_with_multiple_sets() {
        let query = Database::update("users")
            .set("name", "Bob")
            .set("email", "bob@example.com")
            .where_eq("id", 1)
            .build()
            .expect("Query build failed");

        let sql = query.sql();
        assert!(sql.contains("UPDATE users"));
    }
}