magic-school-bus 0.7.0

use crate::{
    input_state::{InputState, InputMode},
    app_state::{AppState, find_should_match},
    virtual_screen::VirtualScreen,
    terminal_context::{Color},
};

fn pad_right_with_spaces(text: &mut String, width: usize) {
    let text_width = text.chars().count();

    if text_width < width {
        for _ in 0..(width - text_width) {
            text.push(' ');
        }
    }
}

/// Ensures that the cursor is always on-screen by adjusting the state's
/// windowing parameters based on the screen size.
pub fn adjust_entry_window(state: &mut AppState, screen: &VirtualScreen) {
    let height = screen.get_size().1;

    let max_item_count = height - 4;

    let window_top = state.entry_window_start;
    let window_bottom = state.entry_window_start + max_item_count;

    if state.cursor <= window_top {
        state.entry_window_start = state.cursor;
    }

    if state.cursor >= window_bottom {
        state.entry_window_start = state.cursor - max_item_count + 1;
    }
}

pub fn render(state: &AppState, input_state: &InputState, screen: &mut VirtualScreen) {
    let (width, height) = screen.get_size();

    let max_item_count = height - 4;
    let window_start = state.entry_window_start;
    let window_size = max_item_count.min(state.entries.len() - window_start);

    let mut working_dir_text = format!("{}", state.working_directory.display());
    pad_right_with_spaces(&mut working_dir_text, width);
    screen.write_str_color(0, 0, &working_dir_text, Color::Black, Color::White);

    let mut widest_entry_width = 0;

    for (index, entry) in state.entries.iter().enumerate() {
        widest_entry_width = widest_entry_width.max(entry.display.chars().count());

        if index >= window_start && index < window_start + window_size {
            let y = 2 + index - window_start;

            enum Highlight {
                Cursor,
                Match,
                None,
            }

            let highlight = match input_state.get_mode() {
                InputMode::FindPrompt => {
                    if index == state.cursor {
                        Highlight::Cursor
                    } else if find_should_match(&entry.display, &state.find_target) {
                        Highlight::Match
                    } else {
                        Highlight::None
                    }
                },
                _ => {
                    if index == state.cursor {
                        Highlight::Cursor
                    } else {
                        Highlight::None
                    }
                },
            };

            match highlight {
                Highlight::Cursor => screen.write_str_color(2, y, &entry.display, Color::Black, Color::White),
                Highlight::Match => screen.write_str_color(2, y, &entry.display, Color::Black, Color::Yellow),
                Highlight::None => screen.write_str(2, y, &entry.display),
            }
        }
    }

    // Draw a border around all the entries
    let end_of_list_line = "-".repeat(widest_entry_width + 4);
    let more_list_line = "~".repeat(widest_entry_width + 4);

    let top_line = if window_start > 0 {
        &more_list_line
    } else {
        &end_of_list_line
    };
    let bottom_line = if window_start + window_size < state.entries.len() {
        &more_list_line
    } else {
        &end_of_list_line
    };

    let entry_vertical_line = "|\n".repeat(window_size);
    screen.write_str(0, 2, &entry_vertical_line);
    screen.write_str(widest_entry_width + 3, 2, &entry_vertical_line);
    screen.write_str(0, 1, top_line);
    screen.write_str(0, 2 + window_size, bottom_line);

    let mut prompt_foreground = Color::Black;
    let mut prompt_background = Color::White;
    let mut status_bar_text = String::new();

    match input_state.get_mode() {
        InputMode::Normal => {
            status_bar_text.push_str("Last action: ");

            match &state.last_action {
                Some(last_action) => {
                    status_bar_text.push_str(&format!("{:?}", last_action));
                },
                None => status_bar_text.push_str("None"),
            };

            if let Some(count) = input_state.get_count_progress() {
                status_bar_text.push_str(" | ");
                status_bar_text.push_str(count);
            }
        },
        InputMode::DeletePrompt => {
            status_bar_text.push_str("Are you sure you want to delete selected? (y or escape)")
        },
        InputMode::FindPrompt => {
            let prompt_string = "Find: ";
            status_bar_text.push_str(prompt_string);

            for &char in input_state.get_text_buffer() {
                status_bar_text.push(char);
            }

            if state.no_find_match {
                prompt_foreground = Color::White;
                prompt_background = Color::Red;
            }

            screen.set_cursor_position(prompt_string.len() + input_state.get_cursor_position(), height - 1);
        },
        InputMode::CommandPrompt => {
            status_bar_text.push(':');

            for &char in input_state.get_text_buffer() {
                status_bar_text.push(char);
            }

            screen.set_cursor_position(1 + input_state.get_cursor_position(), height - 1);
        },
        InputMode::NewFilePrompt => {
            let prompt_string = "New file: ";
            status_bar_text.push_str(prompt_string);

            for &char in input_state.get_text_buffer() {
                status_bar_text.push(char);
            }

            screen.set_cursor_position(prompt_string.len() + input_state.get_cursor_position(), height - 1);
        },
        InputMode::NewDirectoryPrompt => {
            let prompt_string = "New dir: ";
            status_bar_text.push_str(prompt_string);

            for &char in input_state.get_text_buffer() {
                status_bar_text.push(char);
            }

            screen.set_cursor_position(prompt_string.len() + input_state.get_cursor_position(), height - 1);
        },
    }

    pad_right_with_spaces(&mut status_bar_text, width);
    screen.write_str_color(0, height - 1, &status_bar_text, prompt_foreground, prompt_background);
}