dfsql/
handler.rs

1use std::collections::HashMap;
2
3use crate::{
4    df::{ApplyStatError, DfExecutor},
5    sql,
6};
7use polars::lazy::frame::LazyFrame;
8
9pub struct LineExecutor {
10    history: Vec<String>,
11    original_df_name: String,
12    original_input: HashMap<String, LazyFrame>,
13    executor: DfExecutor,
14}
15
16impl LineExecutor {
17    pub fn new(executor: DfExecutor) -> Self {
18        let original_df_name = executor.df_name().clone();
19        let original_input = executor.input().clone();
20        Self {
21            history: vec![],
22            original_df_name,
23            original_input,
24            executor,
25        }
26    }
27
28    pub fn reset(&mut self) {
29        self.executor =
30            DfExecutor::new(self.original_df_name.clone(), self.original_input.clone()).unwrap();
31        self.history.clear();
32    }
33
34    pub fn undo(&mut self) -> anyhow::Result<()> {
35        self.executor =
36            DfExecutor::new(self.original_df_name.clone(), self.original_input.clone()).unwrap();
37        self.history.pop();
38        let sql = self.history.iter().map(|s| sql::parse(s).unwrap());
39        apply_history(sql, &mut self.executor)?;
40        Ok(())
41    }
42
43    pub fn execute(&mut self, line: String) -> anyhow::Result<()> {
44        let s = sql::parse(&line)?;
45        self.executor.execute(&s)?;
46        if !line.trim().is_empty() {
47            self.history.push(line);
48        }
49        Ok(())
50    }
51
52    pub fn df(&self) -> &LazyFrame {
53        self.executor.df()
54    }
55    pub fn df_mut(&mut self) -> &mut LazyFrame {
56        self.executor.df_mut()
57    }
58
59    pub fn history(&self) -> &Vec<String> {
60        &self.history
61    }
62}
63
64fn apply_history(
65    sql: impl Iterator<Item = sql::S>,
66    executor: &mut DfExecutor,
67) -> Result<(), ApplyStatError> {
68    for s in sql {
69        executor.execute(&s)?;
70    }
71    Ok(())
72}
dfsql/handler.rs

dfsql/
handler.rs
