// Copyright 2023 Greptime Team
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use snafu::ResultExt;
use sqlparser::ast::Statement as SpStatement;

use crate::error::{self, Result};
use crate::parser::ParserContext;
use crate::statements::delete::Delete;
use crate::statements::statement::Statement;

/// DELETE statement parser implementation
impl ParserContext<'_> {
    pub(crate) fn parse_delete(&mut self) -> Result<Statement> {
        let token = self.parser.next_token();
        let spstatement = self
            .parser
            .parse_delete(token)
            .context(error::SyntaxSnafu)?;

        match spstatement {
            SpStatement::Delete { .. } => {
                Ok(Statement::Delete(Box::new(Delete { inner: spstatement })))
            }
            unexp => error::UnsupportedSnafu {
                keyword: unexp.to_string(),
            }
            .fail(),
        }
    }
}

#[cfg(test)]
mod tests {
    use std::assert_matches;

    use super::*;
    use crate::dialect::GreptimeDbDialect;
    use crate::parser::ParseOptions;

    #[test]
    pub fn test_parse_insert() {
        let sql = r"delete from my_table where k1 = xxx and k2 = xxx and timestamp = xxx;";
        let result =
            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default())
                .unwrap();
        assert_eq!(1, result.len());
        assert_matches!(result[0], Statement::Delete { .. })
    }

    #[test]
    pub fn test_parse_invalid_insert() {
        let sql = r"delete my_table where "; // intentionally a bad sql
        let result =
            ParserContext::create_with_dialect(sql, &GreptimeDbDialect {}, ParseOptions::default());
        assert!(result.is_err(), "result is: {result:?}");
    }
}
