reifydb_routine/function/datetime/
subtract.rs

1// SPDX-License-Identifier: Apache-2.0
2// Copyright (c) 2025 ReifyDB
3
4use reifydb_core::value::column::{ColumnWithName, buffer::ColumnBuffer, columns::Columns};
5use reifydb_type::value::{container::temporal::TemporalContainer, date::Date, datetime::DateTime, r#type::Type};
6
7use crate::routine::{Function, FunctionKind, Routine, RoutineInfo, context::FunctionContext, error::RoutineError};
8
9pub struct DateTimeSubtract {
10	info: RoutineInfo,
11}
12
13impl Default for DateTimeSubtract {
14	fn default() -> Self {
15		Self::new()
16	}
17}
18
19impl DateTimeSubtract {
20	pub fn new() -> Self {
21		Self {
22			info: RoutineInfo::new("datetime::subtract"),
23		}
24	}
25}
26
27impl<'a> Routine<FunctionContext<'a>> for DateTimeSubtract {
28	fn info(&self) -> &RoutineInfo {
29		&self.info
30	}
31
32	fn return_type(&self, _input_types: &[Type]) -> Type {
33		Type::DateTime
34	}
35
36	fn execute(&self, ctx: &mut FunctionContext<'a>, args: &Columns) -> Result<Columns, RoutineError> {
37		if args.len() != 2 {
38			return Err(RoutineError::FunctionArityMismatch {
39				function: ctx.fragment.clone(),
40				expected: 2,
41				actual: args.len(),
42			});
43		}
44
45		let dt_col = &args[0];
46		let dur_col = &args[1];
47		let (dt_data, dt_bitvec) = dt_col.unwrap_option();
48		let (dur_data, dur_bitvec) = dur_col.unwrap_option();
49		let row_count = dt_data.len();
50
51		let result_data = match (dt_data, dur_data) {
52			(ColumnBuffer::DateTime(dt_container), ColumnBuffer::Duration(dur_container)) => {
53				let mut container = TemporalContainer::with_capacity(row_count);
54
55				for i in 0..row_count {
56					match (dt_container.get(i), dur_container.get(i)) {
57						(Some(dt), Some(dur)) => {
58							let date = dt.date();
59							let time = dt.time();
60							let mut year = date.year();
61							let mut month = date.month() as i32;
62							let mut day = date.day();
63
64							// Subtract months component
65							let total_months = month - dur.get_months();
66							year += (total_months - 1).div_euclid(12);
67							month = (total_months - 1).rem_euclid(12) + 1;
68
69							// Clamp day to valid range for the new month
70							let max_day = days_in_month(year, month as u32);
71							if day > max_day {
72								day = max_day;
73							}
74
75							// Convert to seconds since epoch and subtract day/nanos
76							// components
77							if let Some(base_date) = Date::new(year, month as u32, day) {
78								let base_days = base_date.to_days_since_epoch() as i64
79									- dur.get_days() as i64;
80								let time_nanos = time.to_nanos_since_midnight() as i64
81									- dur.get_nanos();
82
83								let total_nanos = base_days as i128
84									* 86_400_000_000_000i128 + time_nanos
85									as i128;
86
87								if total_nanos >= 0 && total_nanos <= u64::MAX as i128 {
88									container.push(DateTime::from_nanos(
89										total_nanos as u64,
90									));
91								} else {
92									return Err(RoutineError::FunctionExecutionFailed {
93										function: ctx.fragment.clone(),
94										reason: "datetime cannot be before Unix epoch".to_string(),
95									});
96								}
97							} else {
98								return Err(RoutineError::FunctionExecutionFailed {
99									function: ctx.fragment.clone(),
100									reason: "datetime cannot be before Unix epoch"
101										.to_string(),
102								});
103							}
104						}
105						_ => container.push_default(),
106					}
107				}
108
109				ColumnBuffer::DateTime(container)
110			}
111			(ColumnBuffer::DateTime(_), other) => {
112				return Err(RoutineError::FunctionInvalidArgumentType {
113					function: ctx.fragment.clone(),
114					argument_index: 1,
115					expected: vec![Type::Duration],
116					actual: other.get_type(),
117				});
118			}
119			(other, _) => {
120				return Err(RoutineError::FunctionInvalidArgumentType {
121					function: ctx.fragment.clone(),
122					argument_index: 0,
123					expected: vec![Type::DateTime],
124					actual: other.get_type(),
125				});
126			}
127		};
128
129		let final_data = match (dt_bitvec, dur_bitvec) {
130			(Some(bv), _) | (_, Some(bv)) => ColumnBuffer::Option {
131				inner: Box::new(result_data),
132				bitvec: bv.clone(),
133			},
134			_ => result_data,
135		};
136
137		Ok(Columns::new(vec![ColumnWithName::new(ctx.fragment.clone(), final_data)]))
138	}
139}
140
141impl Function for DateTimeSubtract {
142	fn kinds(&self) -> &[FunctionKind] {
143		&[FunctionKind::Scalar]
144	}
145}
146
147fn days_in_month(year: i32, month: u32) -> u32 {
148	match month {
149		1 | 3 | 5 | 7 | 8 | 10 | 12 => 31,
150		4 | 6 | 9 | 11 => 30,
151		2 => {
152			if (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0) {
153				29
154			} else {
155				28
156			}
157		}
158		_ => 0,
159	}
160}
reifydb_routine/function/datetime/subtract.rs

reifydb_routine/function/datetime/
subtract.rs
