-- Filetypes and compatibility
vim.opt.compatible = false
vim.cmd("filetype on")
vim.cmd("filetype plugin on")
vim.cmd("syntax on")

-- Spell
vim.opt.spell = true
vim.opt.spl = "en_us,de_de"
vim.opt.sps = "fast,timeout:100"

-- Editor configuration
vim.opt.number = true
vim.opt.tabstop = 4
vim.opt.shiftwidth = 4
vim.opt.expandtab = true
vim.opt.splitright = true
vim.opt.splitbelow = true
vim.opt.relativenumber = false
vim.g.mapleader = ","
vim.cmd("set clipboard+=unnamedplus")
vim.cmd("autocmd! CursorHold,CursorHoldI *.md write")
vim.cmd("set autoread")

-- GUI
vim.opt.cursorline = true
vim.opt.hlsearch = true
vim.opt.encoding = "UTF-8"
vim.g.tex_flavor = "latex"
vim.opt.conceallevel = 2
vim.opt.showmatch = true

-- set color scheme
vim.opt.termguicolors = true
vim.cmd("colorscheme slate")
vim.keymap.set("n", "<M-+>", ":colo tokyonight-day<CR>")
vim.keymap.set("n", "<M-->", ":colo tokyonight-night<CR>")

-- vim.opt.mouse = ""

-- set copy mode
vim.keymap.set("n", "<leader>ll", ":set nonumber<cr>")
vim.keymap.set("n", "<leader>lm", ":set number<cr>")

-- switch mode
vim.keymap.set("n", "<leader>na", ":set norelativenumber<cr>")
vim.keymap.set("n", "<leader>nr", ":set relativenumber<cr>")

-- Nix mode
local nix_interpreter_buffer = -1
local nix_interpreter_window = -1

-- @name run_nix_interpreter
-- @param
-- @short Run nix and output to a buffer on the right
local function run_nix_interpreter()
	local original_win = vim.api.nvim_get_current_win()
	vim.cmd("vsplit")
	nix_interpreter_buffer = vim.api.nvim_create_buf(false, true)
	vim.api.nvim_win_set_buf(0, nix_interpreter_buffer)
	nix_interpreter_window = vim.api.nvim_get_current_win()
	vim.api.nvim_set_current_win(original_win)
end

-- @name update_nix_interpreter
-- @param
-- @short Run nix enterpreter on that file.
local function update_nix_interpreter()
	local filename = vim.api.nvim_buf_get_name(0)
	if filename == "" then
		vim.api.nvim_buf_set_lines(nix_interpreter_buffer, 0, -1, false, {
			"Error: Current buffer has no file name.",
		})
		return
	end
	local cmd = { "nix-instantiate", "--eval", "--strict", filename }
	local output = vim.fn.systemlist(cmd)
	if vim.v.shell_error ~= 0 then
		table.insert(output, 1, "Error running nix-instantiate:")
	end
	vim.api.nvim_buf_set_lines(nix_interpreter_buffer, 0, -1, false, output)
end

-- @name close_nix_interpreter
-- @param
-- @short Closes the window and buffer of the interpreter
local function close_nix_interpreter()
	vim.api.nvim_buf_delete(nix_interpreter_buffer, { unload = true })
	vim.api.nvim_win_close(nix_interpreter_window, true)
end

vim.api.nvim_create_autocmd({ "BufEnter" }, {
	pattern = { "*.nix" },
	callback = run_nix_interpreter,
})

vim.api.nvim_create_autocmd({ "BufWritePost" }, {
	pattern = { "*.nix" },
	callback = update_nix_interpreter,
})

vim.api.nvim_create_autocmd({ "BufLeave" }, {
	pattern = { "*.nix" },
	callback = close_nix_interpreter,
})