use std::time::{Duration, Instant};
use anyhow::{Context, Result};
use crossterm::event::{self, Event, KeyCode, KeyEventKind, KeyModifiers, MouseEventKind};
use super::super::{
EVENT_DRAIN_BUDGET, EVENT_DRAIN_LIMIT, MOUSE_HORIZONTAL_COLUMNS, MOUSE_SCROLL_LINES,
};
use super::{
jump::{handle_jump_input_key, push_jump_digit},
keys::{accepts_jump_digit, plain_key},
scroll::{
page_down, page_up, reset_top_row_offset, scroll_down, scroll_down_by, scroll_up,
scroll_up_by, scroll_x_by, set_file_end, set_top,
},
search::{
SearchDirection, cancel_search_task, clear_search_message, handle_search_input_key,
start_repeat_search, start_search_prompt,
},
state::{EventAction, ViewState},
structure::{StructureDirection, start_structure_navigation},
};
pub(in crate::viewer) fn drain_events(
state: &mut ViewState,
line_count: usize,
line_count_exact: bool,
page: usize,
) -> Result<EventAction> {
let started = Instant::now();
let mut action = EventAction::default();
let mut processed = 0;
loop {
let event = event::read().context("failed to read terminal event")?;
let next = handle_event_with_count(event, state, line_count, line_count_exact, page);
let needs_layout = next.dirty && state.wrap_bounds_stale;
action.merge(next);
processed += 1;
if action.quit
|| needs_layout
|| processed >= EVENT_DRAIN_LIMIT
|| started.elapsed() >= EVENT_DRAIN_BUDGET
|| !event::poll(Duration::ZERO).context("failed to poll terminal event")?
{
break;
}
}
Ok(action)
}
#[cfg(test)]
pub(in crate::viewer) fn handle_event(
event: Event,
state: &mut ViewState,
line_count: usize,
page: usize,
) -> EventAction {
handle_event_with_count(event, state, line_count, true, page)
}
pub(in crate::viewer) fn handle_event_with_count(
event: Event,
state: &mut ViewState,
line_count: usize,
line_count_exact: bool,
page: usize,
) -> EventAction {
match event {
Event::Key(key) if key.kind == KeyEventKind::Release => EventAction::default(),
Event::Key(key) => handle_key_event_with_count(
key.code,
key.modifiers,
state,
line_count,
line_count_exact,
page,
),
Event::Mouse(mouse) if !state.has_active_prompt() => {
handle_mouse_event(mouse.kind, mouse.modifiers, state, line_count)
}
Event::Mouse(_) => EventAction::default(),
Event::Resize(_, _) => EventAction {
dirty: true,
quit: false,
mouse_capture: None,
},
_ => EventAction::default(),
}
}
#[cfg(test)]
pub(in crate::viewer) fn handle_key_event(
code: KeyCode,
modifiers: KeyModifiers,
state: &mut ViewState,
line_count: usize,
page: usize,
) -> EventAction {
handle_key_event_with_count(code, modifiers, state, line_count, true, page)
}
pub(in crate::viewer) fn handle_key_event_with_count(
code: KeyCode,
modifiers: KeyModifiers,
state: &mut ViewState,
line_count: usize,
line_count_exact: bool,
page: usize,
) -> EventAction {
if matches!(code, KeyCode::Char('c')) && modifiers.contains(KeyModifiers::CONTROL) {
return EventAction {
dirty: false,
quit: true,
mouse_capture: None,
};
}
if state.search_active {
return EventAction {
dirty: handle_search_input_key(code, modifiers, state, line_count),
quit: false,
mouse_capture: None,
};
}
if !state.jump_buffer.is_empty() {
return EventAction {
dirty: handle_jump_input_key(code, modifiers, state, line_count, line_count_exact),
quit: false,
mouse_capture: None,
};
}
let dirty = match code {
KeyCode::Char(ch) if accepts_jump_digit(ch, modifiers) => {
push_jump_digit(state, ch);
true
}
KeyCode::Char('/') if plain_key(modifiers) => start_search_prompt(state),
KeyCode::Char('n') if plain_key(modifiers) => {
start_repeat_search(state, line_count, SearchDirection::Forward)
}
KeyCode::Char('N') if plain_key(modifiers) => {
start_repeat_search(state, line_count, SearchDirection::Backward)
}
KeyCode::Char(']') if plain_key(modifiers) => start_structure_navigation(
state,
line_count,
line_count_exact,
StructureDirection::Forward,
),
KeyCode::Char('[') if plain_key(modifiers) => start_structure_navigation(
state,
line_count,
line_count_exact,
StructureDirection::Backward,
),
KeyCode::Enter => false,
KeyCode::Esc if state.search_task.is_some() => cancel_search_task(state),
KeyCode::Esc if state.search_message.is_some() => clear_search_message(state),
KeyCode::Char('q') | KeyCode::Esc => {
return EventAction {
dirty: false,
quit: true,
mouse_capture: None,
};
}
KeyCode::Char('m') if plain_key(modifiers) => {
state.mouse_capture = !state.mouse_capture;
return EventAction {
dirty: true,
quit: false,
mouse_capture: Some(state.mouse_capture),
};
}
KeyCode::Char('w') => {
state.wrap = !state.wrap;
reset_top_row_offset(state);
true
}
KeyCode::Down | KeyCode::Char('j') => {
let dirty = scroll_down(state, line_count);
clear_structure_cursor_if_dirty(state, dirty)
}
KeyCode::Up | KeyCode::Char('k') => {
let dirty = scroll_up(state, line_count);
clear_structure_cursor_if_dirty(state, dirty)
}
KeyCode::PageDown | KeyCode::Char(' ') | KeyCode::Char('f') => {
let dirty = page_down(state, line_count, page);
clear_structure_cursor_if_dirty(state, dirty)
}
KeyCode::PageUp | KeyCode::Char('b') => {
let dirty = page_up(state, line_count, page);
clear_structure_cursor_if_dirty(state, dirty)
}
KeyCode::Home | KeyCode::Char('g') => {
let dirty = set_top(state, 0);
clear_structure_cursor_if_dirty(state, dirty)
}
KeyCode::End | KeyCode::Char('G') => {
let dirty = set_file_end(state, line_count);
clear_structure_cursor_if_dirty(state, dirty)
}
KeyCode::Right | KeyCode::Char('l') if !state.wrap => {
scroll_x_by(&mut state.x, MOUSE_HORIZONTAL_COLUMNS as isize)
}
KeyCode::Left | KeyCode::Char('h') if !state.wrap => {
scroll_x_by(&mut state.x, -(MOUSE_HORIZONTAL_COLUMNS as isize))
}
_ => false,
};
EventAction {
dirty,
quit: false,
mouse_capture: None,
}
}
pub(in crate::viewer) fn handle_mouse_event(
kind: MouseEventKind,
modifiers: KeyModifiers,
state: &mut ViewState,
line_count: usize,
) -> EventAction {
let dirty = match kind {
MouseEventKind::ScrollDown if modifiers.contains(KeyModifiers::SHIFT) && !state.wrap => {
scroll_x_by(&mut state.x, MOUSE_HORIZONTAL_COLUMNS as isize)
}
MouseEventKind::ScrollUp if modifiers.contains(KeyModifiers::SHIFT) && !state.wrap => {
scroll_x_by(&mut state.x, -(MOUSE_HORIZONTAL_COLUMNS as isize))
}
MouseEventKind::ScrollDown => {
let dirty = scroll_down_by(state, line_count, MOUSE_SCROLL_LINES);
clear_structure_cursor_if_dirty(state, dirty)
}
MouseEventKind::ScrollUp => {
let dirty = scroll_up_by(state, line_count, MOUSE_SCROLL_LINES);
clear_structure_cursor_if_dirty(state, dirty)
}
MouseEventKind::ScrollRight if !state.wrap => {
scroll_x_by(&mut state.x, MOUSE_HORIZONTAL_COLUMNS as isize)
}
MouseEventKind::ScrollLeft if !state.wrap => {
scroll_x_by(&mut state.x, -(MOUSE_HORIZONTAL_COLUMNS as isize))
}
_ => false,
};
EventAction {
dirty,
quit: false,
mouse_capture: None,
}
}
fn clear_structure_cursor_if_dirty(state: &mut ViewState, dirty: bool) -> bool {
if dirty {
state.structure_cursor = None;
state.preserve_tail_on_next_draw = false;
}
dirty
}