local utilities = require('sherlock5512.utilities')
local required = {"lspkind","luasnip","cmp"}
local modules = utilities.require_modules(required)

if not modules then
	return
end

-- lspkind MUST be initialised before use
modules.lspkind.init()

-- I define a default set of configs that are shared across all filetypes,
-- This way I can have fietype specific configs without using autocommands.
local defaultSources = modules.cmp.config.sources({
	{ name = "nvim_lsp" },
	{ name = "luasnip" },
	{ name = "path" },
})

local defaultSnippet = {
	expand = function (args)
		modules.luasnip.lsp_expand(args.body)
	end
}

local defaultMapping = {
	["<Tab>"] = modules.cmp.mapping(function(fallback)
		if modules.cmp.visible() then
			modules.cmp.select_next_item()
		elseif modules.luasnip.expand_or_locally_jumpable() then
			modules.luasnip.expand_or_jump()
		else
			fallback()
		end
	end, {"i","s"}),

	["<S-Tab>"] = modules.cmp.mapping(function(fallback)
		if modules.cmp.visible() then
			modules.cmp.select_prev_item()
		elseif modules.luasnip.locally_jumpable(-1) then
			modules.luasnip.jump(-1)
		else
			fallback()
		end
	end, {"i","s"}),

	["<C-n>"] = modules.cmp.mapping.select_next_item {behaviour = modules.cmp.SelectBehavior.Insert},
	["<C-p>"] = modules.cmp.mapping.select_prev_item {behaviour = modules.cmp.SelectBehavior.Insert},
	["<C-b>"] = modules.cmp.mapping.scroll_docs(-4),
	["<C-f>"] = modules.cmp.mapping.scroll_docs(4),
	["<C-e>"] = modules.cmp.mapping.abort(),
	["<CR>"] = modules.cmp.mapping.confirm({ select = false })
}

local defaultFormat = modules.lspkind.cmp_format ({
	mode = "symbol_text",
	menu = {
		buffer =	"[BUF]",
		nvim_lsp =	"[LSP]",
		path =		"[PTH]",
		luasnip =	"[SNP]",
		emoji =		"[EMJ]",
	},
	maxwidth = 50,
	ellipsis_char = "…"
})

modules.cmp.setup {
	snippet = defaultSnippet,
	sources = defaultSources,
	mapping = defaultMapping,
	formatting = {
		format = defaultFormat
	}
}

-- I'm not sure if the mappings are referenced after configuring,
-- Just in case I deepcopy them before changing things.
local mdSources = vim.deepcopy(defaultSources)
table.insert(mdSources,{ name = "emoji"} )

modules.cmp.setup.filetype('markdown',{
	snippet = defaultSnippet,
	sources = mdSources,
	mapping = defaultMapping,
})

-- completion for searches
modules.cmp.setup.cmdline({ '/', '?' }, {
	mapping = modules.cmp.mapping.preset.cmdline(),
	sources = {
		{ name = 'buffer' }
	}
})

modules.cmp.setup.cmdline(':', {
	mapping = modules.cmp.mapping.preset.cmdline(),
	sources = modules.cmp.config.sources({
		{ name = 'path' }
	}, {
		{ name = 'cmdline' }
	})
})