--[
-- Completion with snippets and LSP and all...
--
-- Very good.
--]
return {
	"hrsh7th/nvim-cmp",
	enabled = true,
	event = "InsertEnter",
	dependencies = {
		"hrsh7th/cmp-nvim-lsp",
		"hrsh7th/cmp-buffer",
		"hrsh7th/cmp-path",
		"hrsh7th/cmp-cmdline",
		"saadparwaiz1/cmp_luasnip",
		"hrsh7th/cmp-nvim-lua",
		"hrsh7th/cmp-vsnip",
		"hrsh7th/vim-vsnip",
		"refamadriz/friendly-snippets",
		"onsails/lspkind.nvim",
		{
			-- TODO: Put that one in its own config file !
			"L3MON4D3/LuaSnip",
			build = "make install_jsregexp",
			version = "v2.*",
			dependencies = {
				"rafamadriz/friendly-snippets",
			},
			opts = { history = true, updateevents = "TextChanged,TextChangedI" },
			config = function()
				local ls = require("luasnip")

				require("luasnip.loaders.from_vscode").lazy_load()
				require("luasnip.loaders.from_snipmate").lazy_load()
				require("luasnip.loaders.from_lua").lazy_load()

				-- print(vim.g.snipmate_snippets_path or "Hello")
				-- print(vim.g.vscode_snippets_path or "Hello2")

				vim.api.nvim_create_autocmd("InsertLeave", {
					callback = function()
						if
							require("luasnip").session.current_nodes[vim.api.nvim_get_current_buf()]
							and not require("luasnip").session.jump_active
						then
							require("luasnip").unlink_current()
						end
					end,
				})

				-- Set keymaps
				vim.keymap.set({ "i" }, "<C-K>", function()
					ls.expand()
				end, { silent = true })
				vim.keymap.set({ "i", "s" }, "<C-L>", function()
					ls.jump(1)
				end, { silent = true })
				vim.keymap.set({ "i", "s" }, "<C-J>", function()
					ls.jump(-1)
				end, { silent = true })

				vim.keymap.set({ "i", "s" }, "<C-E>", function()
					if ls.choice_active() then
						ls.change_choice(1)
					end
				end, { silent = true })
			end,
		},
	},
	config = function()
		local cmp = require("cmp")
		local luasnip = require("luasnip")
		local lspkind = require("lspkind")

		--NOTE:
		--  Ctrl + Space (insert mode)=> to trigger completion.

		cmp.setup({
			completion = {
				-- DOC: This is just help.
				-- - menuone: popup even when there's only one match
				-- - noinsert: Do not insert text until a selection is made
				-- - noselect: Do not select, force to select one from the menu
				-- - shortness: avoid showing extra messages when using completion
				-- - updatetime: set updatetime for CursorHold
				-- Check :help completeopt
				completeopt = "menu,menuone,preview,noselect",
			},
			-- Select a snippet engine.
			snippet = {
				expand = function(args)
					luasnip.lsp_expand(args.body)
				end,
			},
			mapping = cmp.mapping.preset.insert({
				["<c-k>"] = cmp.mapping.select_prev_item(),
				["<c-j>"] = cmp.mapping.select_next_item(),
				["<c-b>"] = cmp.mapping.scroll_docs(-4),
				["<c-f>"] = cmp.mapping.scroll_docs(4),
				["<c-space>"] = cmp.mapping.complete(),
				["<c-e>"] = cmp.mapping.abort(),
				["<CR>"] = cmp.mapping.confirm({ select = true }),
			}),

			-- Order is important !
			sources = {
				{ name = "nvim_lsp_signature_help", keyword_length = 2 },
				{ name = "nvim_lsp", keyword_length = 2 }, -- lsp completion
				{ name = "nvim-lua", keyword_length = 2 },
				{ name = "luasnip", keyword_length = 3 }, -- snippets
				{ name = "buffer", keyword_length = 3 }, -- text within current buffer
				{ name = "path" }, -- system path
				{ name = "calc" }, -- source for math calculation !
			},
			window = {
				completion = cmp.config.window.bordered(),
				documentation = cmp.config.window.bordered(),
			},
			formatting = {
				expandable_indicator = true,
				fields = { cmp.ItemField.Kind, cmp.ItemField.Abbr, cmp.ItemField.Menu },
				--[[
        -- TODO: Use that icons ! 🥳
        format = function(entry, item)
          local menu_icon = {
            nvim_lsp = "λ",
            vsnip = "⋗",
            buffer = "Ω",
            path = "🖫",
          }
          item.menu = menu_icon[entry.source.name]
          return item
        end,
        --]]
				format = lspkind.cmp_format({
					maxwidth = 50,
					ellipsis_char = "...",
				}),
			},
		})

		-- Use cmdline & path source for ':' (if you enabled `native_menu`, this won't work anymore).
		cmp.setup.cmdline(":", {
			-- mapping = cmp.mapping.preset.cmdline(),
			mapping = cmp.mapping.preset.cmdline({
				["<S-CR>"] = {
					c = function(default)
						if cmp.visible() then
							return cmp.confirm({ select = true })
						end

						default()
					end,
				},
			}),
			sources = cmp.config.sources({
				{ name = "path" },
			}, {
				{ name = "cmdline" },
			}),
		})
	end,
}