mlux 2.2.1

A rich Markdown viewer for modern terminals
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
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159

use std::time::Duration;

use log::debug;

// ---------------------------------------------------------------------------
// Config — resolved (all fields concrete)
// ---------------------------------------------------------------------------

pub struct Config {
    pub theme: String,
    pub width: f64,
    pub ppi: f32,
    pub viewer: ViewerConfig,
}

/// User-facing scroll-behavior choice.  Config carries only the
/// selection; the viewer maps each variant to a concrete strategy
/// implementation.
#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
pub enum ScrollMode {
    /// Constant step per keypress (classic behavior).
    #[default]
    Fixed,
    /// Input-density-driven multiplier (experimental).
    Adaptive,
}

pub struct ViewerConfig {
    pub scroll_step: u32,
    pub scroll_mode: ScrollMode,
    pub frame_budget: Duration,
    pub tile_height: f64,
    pub sidebar_cols: u16,
    pub evict_distance: usize,
    pub watch_interval: Duration,
}

impl Default for Config {
    fn default() -> Self {
        Self {
            theme: crate::theme::DEFAULT_THEME.into(),
            width: 660.0,
            ppi: 144.0,
            viewer: ViewerConfig::default(),
        }
    }
}

impl Default for ViewerConfig {
    fn default() -> Self {
        Self {
            scroll_step: 3,
            scroll_mode: ScrollMode::default(),
            frame_budget: Duration::from_millis(32),
            tile_height: 500.0,
            sidebar_cols: 6,
            evict_distance: 4,
            watch_interval: Duration::from_millis(200),
        }
    }
}

impl Config {
    /// Apply CLI overrides to this config.
    pub fn apply_cli(&mut self, cli: &CliOverrides) {
        if let Some(ref v) = cli.theme {
            debug!("config: CLI override theme={v}");
            self.theme = v.clone();
        }
        if let Some(v) = cli.width {
            debug!("config: CLI override width={v}");
            self.width = v;
        }
        if let Some(v) = cli.ppi {
            debug!("config: CLI override ppi={v}");
            self.ppi = v;
        }
        if let Some(v) = cli.tile_height {
            debug!("config: CLI override tile_height={v}");
            self.viewer.tile_height = v;
        }
        if let Some(mode) = cli.scroll_mode {
            debug!("config: CLI override scroll_mode={mode:?}");
            self.viewer.scroll_mode = mode;
            // Note: `scroll_step` is NOT coerced here.  It applies only
            // to the `Fixed` strategy; `Adaptive` uses its own internal
            // base (see `src/viewer/scroll_policy.rs`) and ignores this
            // setting entirely.  Earlier revisions coerced `scroll_step
            // = 2` for adaptive, which mixed user preference with
            // algorithm tuning — keeping them disjoint is the fix.
        }
    }
}

// ---------------------------------------------------------------------------
// CliOverrides — values from CLI args
// ---------------------------------------------------------------------------

#[derive(Clone, Default)]
pub struct CliOverrides {
    pub theme: Option<String>,
    pub width: Option<f64>,
    pub ppi: Option<f32>,
    pub tile_height: Option<f64>,
    pub allow_remote_images: bool,
    pub scroll_mode: Option<ScrollMode>,
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn defaults() {
        let config = Config::default();
        assert_eq!(config.theme, "auto");
        assert_eq!(config.width, 660.0);
        assert_eq!(config.ppi, 144.0);
        assert_eq!(config.viewer.scroll_step, 3);
        assert_eq!(config.viewer.scroll_mode, ScrollMode::Fixed);
        assert_eq!(config.viewer.sidebar_cols, 6);
        assert_eq!(config.viewer.evict_distance, 4);
    }

    #[test]
    fn cli_overrides() {
        let mut config = Config::default();
        let cli = CliOverrides {
            theme: Some("dark".into()),
            width: None,
            ppi: Some(288.0),
            tile_height: None,
            allow_remote_images: false,
            scroll_mode: None,
        };
        config.apply_cli(&cli);
        assert_eq!(config.theme, "dark");
        assert_eq!(config.ppi, 288.0);
        assert_eq!(config.width, 660.0); // unchanged
    }

    #[test]
    fn scroll_mode_override_does_not_touch_scroll_step() {
        // `scroll_step` is the user's canonical preference; selecting
        // adaptive mode must not silently rewrite it.  The adaptive
        // algorithm scales off whatever the user configured.
        for mode in [ScrollMode::Fixed, ScrollMode::Adaptive] {
            let mut config = Config::default();
            assert_eq!(config.viewer.scroll_step, 3);
            let cli = CliOverrides {
                scroll_mode: Some(mode),
                ..Default::default()
            };
            config.apply_cli(&cli);
            assert_eq!(config.viewer.scroll_mode, mode);
            assert_eq!(config.viewer.scroll_step, 3); // unchanged
        }
    }
}