mempal 0.1.0

Project memory for coding agents. Single binary, hybrid search, knowledge graph.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140

use std::collections::BTreeSet;
use std::time::{SystemTime, UNIX_EPOCH};

use sha2::{Digest, Sha256};

use super::types::TaxonomyEntry;

pub const DEFAULT_ROOM: &str = "default";

pub fn build_drawer_id(wing: &str, room: Option<&str>, content: &str) -> String {
    let room = room.unwrap_or(DEFAULT_ROOM);
    let mut hasher = Sha256::new();
    hasher.update(content.as_bytes());
    let digest = format!("{:x}", hasher.finalize());

    format!(
        "drawer_{}_{}_{}",
        sanitize_component(wing),
        sanitize_component(room),
        &digest[..8]
    )
}

pub fn build_triple_id(subject: &str, predicate: &str, object: &str) -> String {
    let mut hasher = Sha256::new();
    hasher.update(subject.as_bytes());
    hasher.update([0]);
    hasher.update(predicate.as_bytes());
    hasher.update([0]);
    hasher.update(object.as_bytes());
    let digest = format!("{:x}", hasher.finalize());

    format!(
        "triple_{}_{}_{}",
        sanitize_component_prefix(subject, 8),
        sanitize_component_prefix(predicate, 8),
        &digest[..8]
    )
}

pub fn current_timestamp() -> String {
    match SystemTime::now().duration_since(UNIX_EPOCH) {
        Ok(duration) => duration.as_secs().to_string(),
        Err(_) => "0".to_string(),
    }
}

pub fn synthetic_source_file(drawer_id: &str) -> String {
    format!("mempal://drawer/{drawer_id}")
}

pub fn source_file_or_synthetic(drawer_id: &str, source_file: Option<&str>) -> String {
    source_file
        .map(str::trim)
        .filter(|value| !value.is_empty())
        .map(ToOwned::to_owned)
        .unwrap_or_else(|| synthetic_source_file(drawer_id))
}

pub fn route_room_from_taxonomy(content: &str, wing: &str, taxonomy: &[TaxonomyEntry]) -> String {
    let normalized_content = content.to_lowercase();
    let content_terms = content_terms(&normalized_content);

    taxonomy
        .iter()
        .filter(|entry| entry.wing == wing)
        .filter_map(|entry| {
            let matched_keywords = matched_keywords(&normalized_content, &content_terms, entry);
            (!matched_keywords.is_empty()).then_some((entry, matched_keywords))
        })
        .max_by(|(left_entry, left_matches), (right_entry, right_matches)| {
            left_matches
                .len()
                .cmp(&right_matches.len())
                .then_with(|| {
                    left_matches
                        .iter()
                        .map(String::len)
                        .sum::<usize>()
                        .cmp(&right_matches.iter().map(String::len).sum::<usize>())
                })
                .then_with(|| left_entry.keywords.len().cmp(&right_entry.keywords.len()))
        })
        .map(|(entry, _)| {
            if entry.room.trim().is_empty() {
                DEFAULT_ROOM.to_string()
            } else {
                entry.room.clone()
            }
        })
        .unwrap_or_else(|| DEFAULT_ROOM.to_string())
}

fn sanitize_component(value: &str) -> String {
    value
        .chars()
        .map(|ch| {
            if ch.is_ascii_alphanumeric() {
                ch.to_ascii_lowercase()
            } else {
                '_'
            }
        })
        .collect()
}

fn sanitize_component_prefix(value: &str, max_len: usize) -> String {
    let sanitized = sanitize_component(value);
    let prefix: String = sanitized.chars().take(max_len).collect();
    if prefix.is_empty() {
        "x".to_string()
    } else {
        prefix
    }
}

fn matched_keywords(
    normalized_content: &str,
    content_terms: &BTreeSet<String>,
    entry: &TaxonomyEntry,
) -> Vec<String> {
    entry
        .keywords
        .iter()
        .map(|keyword| keyword.trim().to_lowercase())
        .filter(|keyword| {
            !keyword.is_empty()
                && (content_terms.contains(keyword)
                    || normalized_content.contains(keyword.as_str()))
        })
        .collect()
}

fn content_terms(content: &str) -> BTreeSet<String> {
    content
        .split(|ch: char| !ch.is_alphanumeric())
        .filter(|term| !term.is_empty())
        .map(ToOwned::to_owned)
        .collect()
}