-- change terminal title
vim.o.title = true

-- default indentation
vim.o.shiftwidth = 2
vim.o.tabstop = 4
vim.o.expandtab = true

-- permanent undo history
vim.o.undofile = true

-- allow switching buffers
vim.o.hidden = true

-- always scroll (keep current line vertically centered)
vim.o.scrolloff = 999

-- show line numbers
vim.o.number = true
vim.o.relativenumber = true

-- set wordwrap indent
vim.o.wrap = false
vim.o.linebreak = true
vim.o.breakindent = true
vim.o.breakindentopt = 'shift:2,sbr'

-- show whitespace
vim.o.list = true

-- disable search highlight
vim.o.hlsearch = false

-- always show sign column to avoid layout shift when staging
vim.o.signcolumn = 'yes'

-- have preview window be a bit taller
vim.o.previewheight = 20

-- make a new copy of the file for backup
-- setting to no or auto messes with filewatchers
vim.o.backupcopy = 'yes'

-- disable modelines
vim.o.modeline = false

-- show preview of lines when using :s
vim.o.inccommand = 'split'

-- mouse only in visual mode
vim.o.mouse = 'v'

-- use POSIX-y shell for !
vim.o.shell = '/bin/sh'

-- diff options, increase linematch to 60 and use histogram algorithm
vim.o.diffopt = 'internal,filler,closeoff,linematch:60,algorithm:histogram'

-- basic keymaps

-- j/k with wraps
vim.keymap.set({ 'n', 'v' }, 'j', 'gj')
vim.keymap.set({ 'n', 'v' }, 'k', 'gk')

-- select pasted text
vim.keymap.set('n', 'gp', '`[v`]')

-- format on save
vim.api.nvim_create_autocmd('BufWritePre', {
  callback = function(opts)
    if vim.bo.filetype == 'diff' then
      return
    end

    if not vim.g.no_lsp_format then
      -- check if can LSP format
      local clients = vim.lsp.get_clients({ bufnr = opts.buf, method = 'textDocument/formatting' })
      if #clients > 0 then
        vim.lsp.buf.format({ bufnr = opts.buf })
      end
    end

    -- otherwise strip trailing whitespace
    vim.cmd('%s/\\s\\+$//e')
  end,
})