rsmixer 0.5.5

use std::{collections::HashSet, mem::discriminant};

use crate::{
	models::{PageType, UserAction},
	repeat, BINDINGS,
};

#[derive(Debug, Clone)]
pub struct HelpLine {
	pub key_events: Vec<String>,
	pub category: String,
}

impl HelpLine {
	pub fn lines_needed(&self, mut w: u16) -> u16 {
		let mut i = 0;
		let mut j = 0;
		w -= self.category.len() as u16;
		self.key_events.iter().for_each(|ke| {
			if i + ke.len() as u16 + 1 > w {
				i = (ke.len() + 1) as u16;
				j += 1;
			} else {
				i += (ke.len() + 1) as u16;
			}
		});

		j + 1
	}

	pub fn as_lines(&self, mut w: u16) -> Vec<String> {
		let mut cur = "".to_string();
		let mut v = Vec::new();
		w -= self.category.len() as u16;
		self.key_events.iter().for_each(|ke| {
			if cur.len() + ke.len() + 1 > w as usize {
				v.push(cur.clone());
				cur = format!("{} ", ke);
			} else {
				cur = format!("{}{} ", cur, ke);
			}
		});

		v.push(cur);

		if !v.is_empty() {
			v[0] = format!(
				"{}{}{}",
				v[0],
				repeat!(" ", w as usize - v[0].len()),
				self.category
			);
		}
		v
	}
}

pub enum ActionMatcher {
	Any(UserAction),
	Concrete(UserAction),
}

impl ActionMatcher {
	fn is_matching(&self, l2: &UserAction) -> bool {
		match self {
			Self::Any(l1) => discriminant(l1) == discriminant(l2),
			Self::Concrete(l1) => l1 == l2,
		}
	}
}

pub fn generate() -> Vec<HelpLine> {
	let mut categories = Vec::new();

	let mut volume_deltas = HashSet::new();

	for (_, v) in (*BINDINGS).get().iter() {
		if let UserAction::RequstChangeVolume(x, _) = v {
			volume_deltas.insert(x.abs());
		}
	}

	categories.push((
		"Navigation".to_string(),
		vec![
			ActionMatcher::Any(UserAction::MoveUp(0)),
			ActionMatcher::Any(UserAction::MoveDown(0)),
		],
	));

	for vd in volume_deltas {
		categories.push((
			format!("Change volume by {}", vd),
			vec![
				ActionMatcher::Concrete(UserAction::RequstChangeVolume(vd, None)),
				ActionMatcher::Concrete(UserAction::RequstChangeVolume(-vd, None)),
			],
		))
	}
	categories.push((
		"Mute/unmute".to_string(),
		vec![ActionMatcher::Concrete(UserAction::RequestMute(None))],
	));
	categories.push((
		"Change page".to_string(),
		vec![ActionMatcher::Any(UserAction::ChangePage(PageType::Output))],
	));
	categories.push((
		"Cycle pages".to_string(),
		vec![ActionMatcher::Any(UserAction::CyclePages(0))],
	));
	categories.push((
		"Context menu".to_string(),
		vec![ActionMatcher::Any(UserAction::OpenContextMenu(None))],
	));
	categories.push((
		"Quit".to_string(),
		vec![ActionMatcher::Any(UserAction::RequestQuit)],
	));

	let mut help_lines = Vec::new();

	for category in categories {
		let mut hl = HelpLine {
			key_events: Vec::new(),
			category: category.0,
		};
		for (k, v) in (*BINDINGS).get().iter() {
			for matcher in &category.1 {
				if matcher.is_matching(v) {
					hl.key_events.push(k.to_string());
				}
			}
		}
		help_lines.push(hl);
	}

	help_lines
}