fixing serialization and deserialization in the data insertion

server/src/table_definition/models.rs

@@ -0,0 +1,91 @@
+// src/table_definition/models.rs
+use tonic::Status;
+
+/// Predefined static field mappings
+// TODO CRITICAL add decimal with optional precision"
+pub const PREDEFINED_FIELD_TYPES: &[(&str, &str)] = &[
+    ("text", "TEXT"),
+    ("string", "TEXT"),
+    ("boolean", "BOOLEAN"),
+    ("timestamp", "TIMESTAMPTZ"),
+    ("timestamptz", "TIMESTAMPTZ"),
+    ("time", "TIMESTAMPTZ"),
+    ("money", "NUMERIC(14, 4)"),
+    ("integer", "INTEGER"),
+    ("int", "INTEGER"),
+    ("biginteger", "BIGINT"),
+    ("bigint", "BIGINT"),
+    ("date", "DATE"),
+];
+
+/// reusable decimal number validation
+pub fn validate_decimal_number_format(num_str: &str, param_name: &str) -> Result<(), Status> {
+    if num_str.is_empty() {
+        return Err(Status::invalid_argument(format!("{} cannot be empty", param_name)));
+    }
+    if num_str.starts_with('+') || num_str.starts_with('-') {
+        return Err(Status::invalid_argument(format!(
+            "{} cannot have explicit positive/negative signs", param_name
+        )));
+    }
+    if num_str.contains('.') {
+        return Err(Status::invalid_argument(format!(
+            "{} must be a whole number (no decimal point)", param_name
+        )));
+    }
+    if num_str.len() > 1 && num_str.starts_with('0') {
+        let trimmed = num_str.trim_start_matches('0');
+        let suggestion = if trimmed.is_empty() { "0" } else { trimmed };
+        return Err(Status::invalid_argument(format!(
+            "{} cannot have leading zeros (use '{}' instead of '{}')",
+            param_name, suggestion, num_str
+        )));
+    }
+    if !num_str.chars().all(|c| c.is_ascii_digit()) {
+        return Err(Status::invalid_argument(format!(
+            "{} contains invalid characters. Only digits allowed", param_name
+        )));
+    }
+    Ok(())
+}
+
+/// reusable field type mapper
+pub fn map_field_type(field_type: &str) -> Result<String, Status> {
+    let lower_field_type = field_type.to_lowercase();
+
+    if lower_field_type.starts_with("decimal(") && lower_field_type.ends_with(')') {
+        let args = lower_field_type.strip_prefix("decimal(").unwrap()
+            .strip_suffix(')').unwrap();
+
+        if let Some((p_str, s_str)) = args.split_once(',') {
+            let precision_str = p_str.trim();
+            let scale_str = s_str.trim();
+
+            validate_decimal_number_format(precision_str, "precision")?;
+            validate_decimal_number_format(scale_str, "scale")?;
+
+            let precision = precision_str.parse::<u32>()
+                .map_err(|_| Status::invalid_argument("Invalid precision"))?;
+            let scale = scale_str.parse::<u32>()
+                .map_err(|_| Status::invalid_argument("Invalid scale"))?;
+
+            if precision < 1 {
+                return Err(Status::invalid_argument("Precision must be >= 1"));
+            }
+            if scale > precision {
+                return Err(Status::invalid_argument("Scale cannot be > precision"));
+            }
+            return Ok(format!("NUMERIC({}, {})", precision, scale));
+        } else {
+            return Err(Status::invalid_argument(
+                "Invalid decimal format. Expected decimal(precision, scale)"
+            ));
+        }
+    }
+
+    PREDEFINED_FIELD_TYPES
+        .iter()
+        .find(|(key, _)| *key == lower_field_type.as_str())
+        .map(|(_, sql_type)| sql_type.to_string())
+        .ok_or_else(|| Status::invalid_argument(format!("Invalid field type: {}", field_type)))
+}