Function try_parse

nodedb-sql/src/ddl_ast/parse/trigger.rs:9–64

(
    upper: &str,
    parts: &[&str],
    trimmed: &str,
)

use crate::error::SqlError;

pub(super) fn try_parse(
    upper: &str,
    parts: &[&str],
    trimmed: &str,
) -> Option<Result<NodedbStatement, SqlError>> {
    (|| -> Result<Option<NodedbStatement>, SqlError> {
        if upper.starts_with("CREATE ") && upper.contains("TRIGGER ") {
            return Ok(Some(parse_create_trigger(upper, trimmed)));
        }
        if upper.starts_with("DROP TRIGGER ") {
            let if_exists = upper.contains("IF EXISTS");
            let name = match extract_name_after_if_exists(parts, "TRIGGER") {
                None => return Ok(None),
                Some(r) => r?,
            };
            let collection = extract_after_keyword(parts, "ON").unwrap_or_default();
            return Ok(Some(NodedbStatement::Automation(
                AutomationStmt::DropTrigger {
                    name,
                    collection,
                    if_exists,
                },
            )));
        }
        if upper.starts_with("ALTER TRIGGER ") {
            // ALTER TRIGGER <name> ENABLE|DISABLE|OWNER TO <new_owner>
            let name = parts.get(2).map(|s| s.to_lowercase()).unwrap_or_default();
            let action = parts.get(3).map(|s| s.to_uppercase()).unwrap_or_default();
            // When action is "OWNER", "TO" is at index 4 and new_owner at index 5.
            let new_owner = if action == "OWNER" {
                parts.get(5).map(|s| s.trim_end_matches(';').to_string())
            } else {
                None
            };
            return Ok(Some(NodedbStatement::Automation(
                AutomationStmt::AlterTrigger {
                    name,
                    action,
                    new_owner,
                },
            )));
        }
        if upper.starts_with("SHOW TRIGGERS") {
            let collection = if upper.starts_with("SHOW TRIGGERS ON ") {
                parts.get(3).map(|s| s.to_string())
            } else {
                None
            };
            return Ok(Some(NodedbStatement::Automation(
                AutomationStmt::ShowTriggers { collection },
            )));
        }
        Ok(None)
    })()
    .transpose()
}

/// Structural extraction for `CREATE [OR REPLACE] [SYNC|DEFERRED] TRIGGER`.