function map(mode, shortcut, command)
    vim.keymap.set(mode, shortcut, command, { noremap = true, silent = true })
end

vim.g.mapleader = ' '   -- <Leader>

-- buffers
map('n', '<Leader>b',   ':buffers<CR>:buffer<Space>')
map('n', '<M-Left>',    ':bprevious<cr>')
map('n', '<M-Right>',   ':bnext<cr>')
map('i', '<M-Left>',    '<esc>:bprevious<cr>')
map('i', '<M-Right>',   '<esc>:bnext<cr>')

--windows
map('n', '<M-S-Left>',  ':wincmd h<cr>')
map('n', '<M-S-Down>',  ':wincmd j<cr>')
map('n', '<M-S-Up>',    ':wincmd k<cr>')
map('n', '<M-S-Right>', ':wincmd l<cr>')
map('i', '<M-S-Left>',  '<esc>:wincmd h<cr>')
map('i', '<M-S-Down>',  '<esc>:wincmd j<cr>')
map('i', '<M-S-Up>',    '<esc>:wincmd k<cr>')
map('i', '<M-S-Right>', '<esc>:wincmd l<cr>')

-- remove word
map('n', '<M-BS>',      'db')
vim.cmd([[map! <M-BS> <C-W>]])  -- TODO: figure out how to do that with lua
map('n', '<C-Del>',     'dw')
map('i', '<C-Del>',     '<C-O>dw')

-- remove whitespace around cursor
map({ 'n', 'i' }, '<C-S-Del>',
    function()
        local row, pos_cursor = unpack(vim.api.nvim_win_get_cursor(0))
        pos_cursor = pos_cursor + 1 -- api / lua is off by one
        local line = vim.api.nvim_get_current_line()
        local pos_start, pos_end = 0, 0

        while (pos_start ~= nil) do
            if (pos_start <= pos_cursor and pos_end >= pos_cursor) then
                local before = line:sub(1, pos_start - 1)
                local after = line:sub(pos_end + 1)
                local space = ''
                if (before:len() > 0 and after:len() > 0) then
                    space = ' '
                end
                vim.api.nvim_set_current_line(before .. space .. after)
                vim.api.nvim_win_set_cursor(0, { row, pos_start - 1 })
                break
            end
            pos_start, pos_end = line:find('%s+', pos_end + 1)
        end
    end
)

-- move buffer without moving cursor
map('n', '<M-Up>',      '<C-y>')
map('n', '<M-Down>',    '<C-e>')

-- system clipboard
map('v', '<Leader>y',   '"+y')
map('n', '<Leader>p',   '"+p')

-- toggle between beginning of line and beginning of text
map({ 'n', 'i', 'v' }, '<Home>',
    function()
        local row, col = unpack(vim.api.nvim_win_get_cursor(0))
        if (col == 0) then
            local col_new = vim.api.nvim_get_current_line():match('^%s*'):len()
            vim.api.nvim_win_set_cursor(0, { row, col_new })
        else
            vim.api.nvim_win_set_cursor(0, { row, 0 })
        end
    end
)

map('n', '<C-F>', '==') -- re-indent line