rusty-bubbles 2.1.0

//! Cleanroom Rust port of upstream Go source file: `table/table.go`
//! Upstream Target Tag / Version: `v2.1.0`
//!
//! <public-docs>
//! # Table
//!
//! A simple table component for Bubble Tea applications.
//! </public-docs>

use crate::help;
use crate::key::{self, Binding};
use crate::viewport;
use rusty_bubbletea::key::KeyPressMsg;
use rusty_bubbletea::model::{Cmd, Msg};
use rusty_lipgloss::{self, Style};
use rusty_x_ansi;

/// Model defines a state for the table widget.
#[derive(Debug)]
pub struct Model {
    /// The key bindings for the table.
    pub key_map: KeyMap,
    /// The help view for the table.
    pub help: help::Model,

    cols: Vec<Column>,
    rows: Vec<Row>,
    cursor: usize,
    focus: bool,
    styles: Styles,

    viewport: viewport::Model,
    start: usize,
    end: usize,
}

/// Row represents one line in the table.
pub type Row = Vec<String>;

/// Column defines the table structure.
#[derive(Debug, Clone)]
pub struct Column {
    /// The title of the column.
    pub title: String,
    /// The width of the column.
    pub width: usize,
}

/// KeyMap defines keybindings. It satisfies to the help.KeyMap interface,
/// which is used to render the help menu.
#[derive(Debug, Clone)]
pub struct KeyMap {
    /// LineUp binding.
    pub line_up: Binding,
    /// LineDown binding.
    pub line_down: Binding,
    /// PageUp binding.
    pub page_up: Binding,
    /// PageDown binding.
    pub page_down: Binding,
    /// HalfPageUp binding.
    pub half_page_up: Binding,
    /// HalfPageDown binding.
    pub half_page_down: Binding,
    /// GotoTop binding.
    pub goto_top: Binding,
    /// GotoBottom binding.
    pub goto_bottom: Binding,
}

/// ShortHelp implements the KeyMap interface.
impl KeyMap {
    /// ShortHelp returns the bindings shown in the abbreviated help view.
    pub fn short_help(&self) -> Vec<Binding> {
        vec![self.line_up.clone(), self.line_down.clone()]
    }

    /// FullHelp returns the bindings shown in the full help view.
    pub fn full_help(&self) -> Vec<Vec<Binding>> {
        vec![
            vec![
                self.line_up.clone(),
                self.line_down.clone(),
                self.goto_top.clone(),
                self.goto_bottom.clone(),
            ],
            vec![
                self.page_up.clone(),
                self.page_down.clone(),
                self.half_page_up.clone(),
                self.half_page_down.clone(),
            ],
        ]
    }
}

impl help::KeyMap for KeyMap {
    fn short_help(&self) -> Vec<Binding> {
        KeyMap::short_help(self)
    }

    fn full_help(&self) -> Vec<Vec<Binding>> {
        KeyMap::full_help(self)
    }
}

/// DefaultKeyMap returns a default set of keybindings.
pub fn default_key_map() -> KeyMap {
    KeyMap {
        line_up: key::new_binding(vec![
            key::with_keys(&["up", "k"]),
            key::with_help("↑/k", "up"),
        ]),
        line_down: key::new_binding(vec![
            key::with_keys(&["down", "j"]),
            key::with_help("↓/j", "down"),
        ]),
        page_up: key::new_binding(vec![
            key::with_keys(&["b", "pgup"]),
            key::with_help("b/pgup", "page up"),
        ]),
        page_down: key::new_binding(vec![
            key::with_keys(&["f", "pgdown", "space"]),
            key::with_help("f/pgdn", "page down"),
        ]),
        half_page_up: key::new_binding(vec![
            key::with_keys(&["u", "ctrl+u"]),
            key::with_help("u", "½ page up"),
        ]),
        half_page_down: key::new_binding(vec![
            key::with_keys(&["d", "ctrl+d"]),
            key::with_help("d", "½ page down"),
        ]),
        goto_top: key::new_binding(vec![
            key::with_keys(&["home", "g"]),
            key::with_help("g/home", "go to start"),
        ]),
        goto_bottom: key::new_binding(vec![
            key::with_keys(&["end", "G"]),
            key::with_help("G/end", "go to end"),
        ]),
    }
}

/// Styles contains style definitions for this list component. By default,
/// these values are generated by [`default_styles`].
#[derive(Debug, Clone)]
pub struct Styles {
    /// The style for the header row.
    pub header: Style,
    /// The style for cells.
    pub cell: Style,
    /// The style for the selected row.
    pub selected: Style,
}

/// DefaultStyles returns a set of default style definitions for this table.
pub fn default_styles() -> Styles {
    Styles {
        selected: rusty_lipgloss::new_style().bold(true).foreground("212"),
        header: rusty_lipgloss::new_style().bold(true).padding(&[0, 1]),
        cell: rusty_lipgloss::new_style().padding(&[0, 1]),
    }
}

/// Option is used to set options in [`new`]. For example:
///
/// ```rust
/// # use rusty_bubbles::table;
/// let table = table::new(vec![table::with_columns(&[table::Column {
///     title: "ID".to_string(),
///     width: 10,
/// }])]);
/// ```
pub type Option = Box<dyn FnOnce(&mut Model)>; // (std::option::Option is used for optionals)

/// New creates a new model for the table widget.
pub fn new(opts: Vec<Option>) -> Model {
    let mut m = Model {
        cursor: 0,
        viewport: viewport::new(vec![viewport::with_height(20)]),

        key_map: default_key_map(),
        help: help::new(),
        styles: default_styles(),

        cols: vec![],
        rows: vec![],
        focus: false,
        start: 0,
        end: 0,
    };

    for opt in opts {
        opt(&mut m);
    }

    m.update_viewport();

    m
}

/// WithColumns sets the table columns (headers).
pub fn with_columns(cols: &[Column]) -> Option {
    let cols = cols.to_vec();
    Box::new(move |m: &mut Model| {
        m.cols = cols;
    })
}

/// WithRows sets the table rows (data).
pub fn with_rows(rows: &[Row]) -> Option {
    let rows = rows.to_vec();
    Box::new(move |m: &mut Model| {
        m.rows = rows;
    })
}

/// WithHeight sets the height of the table.
pub fn with_height(h: usize) -> Option {
    Box::new(move |m: &mut Model| {
        let hh = rusty_lipgloss::size::height(&m.headers_view());
        m.viewport.set_height(h - hh);
    })
}

/// WithWidth sets the width of the table.
pub fn with_width(w: usize) -> Option {
    Box::new(move |m: &mut Model| {
        m.viewport.set_width(w);
    })
}

/// WithFocused sets the focus state of the table.
pub fn with_focused(f: bool) -> Option {
    Box::new(move |m: &mut Model| {
        m.focus = f;
    })
}

/// WithStyles sets the table styles.
pub fn with_styles(s: Styles) -> Option {
    Box::new(move |m: &mut Model| {
        m.styles = s;
    })
}

/// WithKeyMap sets the key map.
pub fn with_key_map(km: KeyMap) -> Option {
    Box::new(move |m: &mut Model| {
        m.key_map = km;
    })
}

impl Model {
    /// SetStyles sets the table styles.
    pub fn set_styles(&mut self, s: Styles) {
        self.styles = s;
        self.update_viewport();
    }

    /// Update is the Bubble Tea update loop.
    pub fn update(&mut self, msg: &dyn Msg) -> Cmd {
        if !self.focus {
            return None;
        }

        if let Some(m) = msg.as_any().downcast_ref::<KeyPressMsg>() {
            let k = &m.0;
            if key::matches(k, std::slice::from_ref(&self.key_map.line_up)) {
                self.move_up(1);
            } else if key::matches(k, std::slice::from_ref(&self.key_map.line_down)) {
                self.move_down(1);
            } else if key::matches(k, std::slice::from_ref(&self.key_map.page_up)) {
                self.move_up(self.viewport.height());
            } else if key::matches(k, std::slice::from_ref(&self.key_map.page_down)) {
                self.move_down(self.viewport.height());
            } else if key::matches(k, std::slice::from_ref(&self.key_map.half_page_up)) {
                self.move_up(self.viewport.height() / 2);
            } else if key::matches(k, std::slice::from_ref(&self.key_map.half_page_down)) {
                self.move_down(self.viewport.height() / 2);
            } else if key::matches(k, std::slice::from_ref(&self.key_map.goto_top)) {
                self.goto_top();
            } else if key::matches(k, std::slice::from_ref(&self.key_map.goto_bottom)) {
                self.goto_bottom();
            }
        }

        None
    }

    /// Focused returns the focus state of the table.
    pub fn focused(&self) -> bool {
        self.focus
    }

    /// Focus focuses the table, allowing the user to move around the rows
    /// and interact.
    pub fn focus(&mut self) {
        self.focus = true;
        self.update_viewport();
    }

    /// Blur blurs the table, preventing selection or movement.
    pub fn blur(&mut self) {
        self.focus = false;
        self.update_viewport();
    }

    /// View renders the component.
    pub fn view(&self) -> String {
        self.headers_view() + "\n" + &self.viewport.view()
    }

    /// HelpView is a helper method for rendering the help menu from the
    /// keymap. Note that this view is not rendered by default and you must
    /// call it manually in your application, where applicable.
    pub fn help_view(&self) -> String {
        self.help.view(&self.key_map)
    }

    /// UpdateViewport updates the list content based on the previously
    /// defined columns and rows.
    pub fn update_viewport(&mut self) {
        let mut rendered_rows: Vec<String> = Vec::with_capacity(self.rows.len());

        // Render only rows from: m.cursor-m.viewport.Height to:
        // m.cursor+m.viewport.Height. Constant runtime, independent of
        // number of rows in a table. Limits the number of renderedRows to a
        // maximum of 2*m.viewport.Height.
        self.start = clamp(
            self.cursor.saturating_sub(self.viewport.height()),
            0,
            self.cursor,
        );
        self.end = clamp(
            self.cursor + self.viewport.height(),
            self.cursor,
            self.rows.len(),
        );
        for i in self.start..self.end {
            rendered_rows.push(self.render_row(i));
        }

        let refs: Vec<&str> = rendered_rows.iter().map(|s| s.as_str()).collect();
        self.viewport
            .set_content(&rusty_lipgloss::join::join_vertical(
                rusty_lipgloss::LEFT,
                &refs,
            ));
    }

    /// SelectedRow returns the selected row.
    pub fn selected_row(&self) -> std::option::Option<Row> {
        if self.cursor >= self.rows.len() {
            return None;
        }

        Some(self.rows[self.cursor].clone())
    }

    /// Rows returns the current rows.
    pub fn rows(&self) -> &[Row] {
        &self.rows
    }

    /// Columns returns the current columns.
    pub fn columns(&self) -> &[Column] {
        &self.cols
    }

    /// SetRows sets a new rows state.
    pub fn set_rows(&mut self, r: &[Row]) {
        self.rows = r.to_vec();

        if self.cursor > self.rows.len().saturating_sub(1) {
            self.cursor = self.rows.len().saturating_sub(1);
        }

        self.update_viewport();
    }

    /// SetColumns sets a new columns state.
    pub fn set_columns(&mut self, c: &[Column]) {
        self.cols = c.to_vec();
        self.update_viewport();
    }

    /// SetWidth sets the width of the viewport of the table.
    pub fn set_width(&mut self, w: usize) {
        self.viewport.set_width(w);
        self.update_viewport();
    }

    /// SetHeight sets the height of the viewport of the table.
    pub fn set_height(&mut self, h: usize) {
        let hh = rusty_lipgloss::size::height(&self.headers_view());
        self.viewport.set_height(h - hh);
        self.update_viewport();
    }

    /// Height returns the viewport height of the table.
    pub fn height(&self) -> usize {
        self.viewport.height()
    }

    /// Width returns the viewport width of the table.
    pub fn width(&self) -> usize {
        self.viewport.width()
    }

    /// Cursor returns the index of the selected row.
    pub fn cursor(&self) -> usize {
        self.cursor
    }

    /// SetCursor sets the cursor position in the table.
    pub fn set_cursor(&mut self, n: usize) {
        self.cursor = clamp(n, 0, self.rows.len().saturating_sub(1));
        self.update_viewport();
    }

    /// MoveUp moves the selection up by any number of rows.
    /// It can not go above the first row.
    pub fn move_up(&mut self, n: usize) {
        // Upstream uses signed ints and clamps to 0; saturating subtraction
        // mirrors that without overflowing.
        self.cursor = clamp(
            self.cursor.saturating_sub(n),
            0,
            self.rows.len().saturating_sub(1),
        );

        let mut offset = self.viewport.y_offset();
        if self.start == 0 {
            offset = clamp(offset, 0, self.cursor);
        } else if self.start < self.viewport.height() {
            offset = clamp(clamp(offset + n, 0, self.cursor), 0, self.viewport.height());
        } else if offset >= 1 {
            offset = clamp(offset + n, 1, self.viewport.height());
        }
        self.viewport.set_y_offset(offset);
        self.update_viewport();
    }

    /// MoveDown moves the selection down by any number of rows.
    /// It can not go below the last row.
    pub fn move_down(&mut self, n: usize) {
        self.cursor = clamp(self.cursor + n, 0, self.rows.len().saturating_sub(1));
        self.update_viewport();

        let mut offset = self.viewport.y_offset();
        if self.end == self.rows.len() && offset > 0 {
            offset = clamp(offset - n, 1, self.viewport.height());
        } else if self.cursor > (self.end - self.start) / 2 && offset > 0 {
            offset = clamp(offset - n, 1, self.cursor);
        } else if offset > 1 {
            // no-op
        } else if self.cursor > offset + self.viewport.height() - 1 {
            offset = clamp(offset + 1, 0, 1);
        }
        self.viewport.set_y_offset(offset);
    }

    /// GotoTop moves the selection to the first row.
    pub fn goto_top(&mut self) {
        let n = self.cursor;
        self.move_up(n);
    }

    /// GotoBottom moves the selection to the last row.
    pub fn goto_bottom(&mut self) {
        let n = self.rows.len();
        self.move_down(n);
    }

    /// FromValues create the table rows from a simple string. It uses `\n`
    /// by default for getting all the rows and the given separator for the
    /// fields on each row.
    pub fn from_values(&mut self, value: &str, separator: &str) {
        let mut rows: Vec<Row> = vec![];
        for line in value.split('\n') {
            let mut r: Row = vec![];
            for field in line.split(separator) {
                r.push(field.to_string());
            }
            rows.push(r);
        }

        self.set_rows(&rows);
    }

    fn headers_view(&self) -> String {
        let mut s: Vec<String> = Vec::with_capacity(self.cols.len());
        for col in &self.cols {
            if col.width == 0 {
                continue;
            }
            let style = rusty_lipgloss::new_style()
                .width(col.width)
                .max_width(col.width)
                .inline(true);
            let rendered_cell = style.render(&rusty_x_ansi::truncate(&col.title, col.width, "…"));
            s.push(self.styles.header.clone().render(&rendered_cell));
        }
        let refs: Vec<&str> = s.iter().map(|x| x.as_str()).collect();
        rusty_lipgloss::join::join_horizontal(rusty_lipgloss::TOP, &refs)
    }

    fn render_row(&self, r: usize) -> String {
        let mut s: Vec<String> = Vec::with_capacity(self.cols.len());
        for (i, value) in self.rows[r].iter().enumerate() {
            if self.cols[i].width == 0 {
                continue;
            }
            let style = rusty_lipgloss::new_style()
                .width(self.cols[i].width)
                .max_width(self.cols[i].width)
                .inline(true);
            let rendered_cell =
                style.render(&rusty_x_ansi::truncate(value, self.cols[i].width, "…"));
            s.push(self.styles.cell.clone().render(&rendered_cell));
        }

        let refs: Vec<&str> = s.iter().map(|x| x.as_str()).collect();
        let row = rusty_lipgloss::join::join_horizontal(rusty_lipgloss::TOP, &refs);

        if r == self.cursor {
            return self.styles.selected.clone().render(&row);
        }

        row
    }
}

fn clamp(v: usize, low: usize, high: usize) -> usize {
    v.max(low).min(high)
}