heirline.lua

local conditions = require("heirline.conditions")
local utils = require("heirline.utils")

local function setup_colours()
	return {
		bright_bg = utils.get_highlight("Folded").bg,
		bright_fg = utils.get_highlight("Folded").fg,
		red = utils.get_highlight("DiagnosticError").fg,
		dark_red = utils.get_highlight("DiffDelete").bg,
		green = utils.get_highlight("DiagnosticOk").fg,
		blue = utils.get_highlight("Function").fg,
		gray = utils.get_highlight("NonText").fg,
		orange = utils.get_highlight("Constant").fg,
		purple = utils.get_highlight("Conditional").fg,
		cyan = utils.get_highlight("Special").fg,
		diag_warn = utils.get_highlight("DiagnosticWarn").fg,
		diag_error = utils.get_highlight("DiagnosticError").fg,
		diag_hint = utils.get_highlight("DiagnosticHint").fg,
		diag_info = utils.get_highlight("DiagnosticInfo").fg,
		git_del = utils.get_highlight("diffDeleted").fg,
		git_add = utils.get_highlight("diffAdded").fg,
		git_change = utils.get_highlight("diffChanged").fg,
	}
end

vim.api.nvim_create_augroup("Heirline", { clear = true })
vim.api.nvim_create_autocmd("ColorScheme", {
	callback = function()
		utils.on_colorscheme(setup_colours)
	end,
	group = "Heirline",
})

local Align = { provider = "%=", hl = { bg = "bright_bg" } }
local Space = { provider = " ", hl = { bg = "bright_bg" } }

-- Status Line Setup
local ViMode = {
	init = function(self)
		self.mode = vim.fn.mode(1)
	end,

	static = {
		mode_names = { -- change the strings if you like it vvvvverbose!
			n = "NORMAL",
			no = "NORMAL",
			nov = "NORMAL",
			noV = "NORMAL",
			["no\22"] = "NORMAL",
			niI = "INSERT",
			niR = "REPLACE",
			niV = "VISUAL",
			nt = "TERMINAL",
			v = "VISUAL",
			vs = "VISUAL",
			V = "V-LINE",
			Vs = "V-BLOCK",
			["\22"] = "V-BLOCK",
			["\22s"] = "V-BLOCK",
			s = "SELECT",
			S = "SELECT LINE",
			["\19"] = "SELECT",
			i = "INSERT",
			ic = "INSERT",
			ix = "INSERT",
			R = "REPLACE",
			Rc = "REPLACE",
			Rx = "REPLACE",
			Rv = "V-REPLACE",
			Rvc = "V-REPLACE",
			Rvx = "V-REPLACE",
			c = "COMMAND",
			cv = "COMMAND",
			r = "...",
			rm = "MORE",
			["r?"] = "CONFIRM",
			["!"] = "SHELL",
			t = "TERMINAL",
		},
		mode_colours = {
			n = "blue",
			i = "green",
			v = "purple",
			V = "purple",
			["\22"] = "purple",
			c = "orange",
			s = "cyan",
			S = "cyan",
			["\19"] = "cyan",
			R = "orange",
			r = "orange",
			["!"] = "red",
			t = "red",
		},
	},
	provider = function(self)
		return "▎ %2(" .. self.mode_names[self.mode] .. "%)"
	end,
	hl = function(self)
		local mode = self.mode:sub(1, 1)
		return { fg = self.mode_colours[mode], bold = true }
	end,
	update = {
		"ModeChanged",
		pattern = "*:*",
		callback = vim.schedule_wrap(function()
			vim.cmd("redrawstatus")
		end),
	},
}

local Git = {
	condition = conditions.is_git_repo,

	init = function(self)
		self.status_dict = vim.b.gitsigns_status_dict
		self.has_changes = self.status_dict.added ~= 0 or self.status_dict.removed ~= 0 or self.status_dict.changed ~= 0
	end,

	hl = { fg = "green" },

	{ -- git branch name
		provider = function(self)
			return " " .. self.status_dict.head
		end,
		hl = { bold = true },
	},
}

local Ruler = {
	-- %l = current line number
	-- %L = number of lines in the buffer
	-- %c = column number
	-- %P = percentage through file of displayed window
	provider = "%7(%l/%3L%):%2c %P",
	hl = { bg = "bright_bg" },
}

local ScrollBar = {
	static = {
		sbar = { "▁", "▂", "▃", "▄", "▅", "▆", "▇", "█" },
		-- Another variant, because the more choice the better.
		-- sbar = { '🭶', '🭷', '🭸', '🭹', '🭺', '🭻' }
	},
	provider = function(self)
		local curr_line = vim.api.nvim_win_get_cursor(0)[1]
		local lines = vim.api.nvim_buf_line_count(0)
		local i = math.floor((curr_line - 1) / lines * #self.sbar) + 1
		return string.rep(self.sbar[i], 2)
	end,
	hl = { fg = "blue", bg = "bright_bg" },
}

local LSPActive = {
	condition = conditions.lsp_attached,
	update = { "LspAttach", "LspDetach" },

	-- You can keep it simple,
	-- provider = " [LSP]",

	-- Or complicate things a bit and get the servers names
	provider = function()
		local names = {}
		for i, server in pairs(vim.lsp.get_active_clients({ bufnr = 0 })) do
			table.insert(names, server.name)
		end
		return table.concat(names, " ")
	end,
	hl = { fg = "green", bold = true },
}

local FileNameBlock = {
	-- let's first set up some attributes needed by this component and it's children
	init = function(self)
		self.filename = vim.api.nvim_buf_get_name(0)
	end,
}

local FileFlags = {
	{
		condition = function()
			return vim.bo.modified
		end,
		provider = "[+]",
		hl = { fg = "green" },
	},
	{
		condition = function()
			return not vim.bo.modifiable or vim.bo.readonly
		end,
		provider = "",
		hl = { fg = "orange" },
	},
}

local FileType = {
	provide = function()
		return string.upper(vim.bo.filetype)
	end,
	hl = { fg = utils.get_highlight("Type").fg, bold = true },
}

local FileName = {
	init = function(self)
		self.lfilename = vim.fn.fnamemodify(self.filename, ":.")
		if self.lfilename == "" then
			self.lfilename = "[No Name]"
		end
	end,
	hl = { fg = utils.get_highlight("Directory").fg },

	flexible = 2,

	{
		provider = function(self)
			return self.lfilename
		end,
	},
	{
		provider = function(self)
			return vim.fn.pathshorten(self.lfilename)
		end,
	},
}

local FileNameModifer = {
	hl = function()
		if vim.bo.modified then
			-- use `force` because we need to override the child's hl foreground
			return { fg = "cyan", bold = true, force = true }
		end
	end,
}

-- Buffer Line Setup
local TablineBufnr = {
	provider = function(self)
		return tostring(self.bufnr) .. ". "
	end,
	hl = "Comment",
}

local TablineFileName = {
	provider = function(self)
		local filename = self.filename
		filename = filename == "" and "[No Name]" or vim.fn.fnamemodify(filename, ":t")
		return filename
	end,
	hl = function(self)
		return { fg = "gray", bold = self.is_active or self.is_visible, italic = true }
	end,
}

local TablineFileFlags = {
	{
		condition = function(self)
			return vim.api.nvim_get_option_value("modified", { buf = self.bufnr })
		end,
		provider = "[+]",
		hl = { fg = "green" },
	},
	{
		condition = function(self)
			return not vim.api.nvim_get_option_value("modifiable", { buf = self.bufnr })
				or vim.api.nvim_get_option_value("readonly", { buf = self.bufnr })
		end,
		provider = function(self)
			if vim.api.nvim_get_option_value("buftype", { buf = self.bufnr }) == "terminal" then
				return "  "
			else
				return ""
			end
		end,
		hl = { fg = "orange" },
	},
}

local TablineFileNameBlock = {
	init = function(self)
		self.filename = vim.api.nvim_buf_get_name(self.bufnr)
	end,
	hl = function(self)
		if self.is_active then
			return "TabLineSel"
		else
			return "TabLine"
		end
	end,
	on_click = {
		callback = function(_, minwid, _, button)
			if button == "m" then
				vim.schedule(function()
					vim.api.nvim_buf_delete(minwid, { force = false })
				end)
			else
				vim.api.nvim_win_set_buf(0, minwid)
			end
		end,
		minwid = function(self)
			return self.bufnr
		end,
		name = "heirline_tabline_buffer_callback",
	},
	-- TablineBufnr,
	TablineFileName,
	TablineFileFlags,
}

-- a nice "x" button to close the buffer
local TablineCloseButton = {
	condition = function(self)
		return not vim.api.nvim_get_option_value("modified", { buf = self.bufnr })
	end,
	{ provider = " " },
	{
		provider = "",
		hl = { fg = "gray" },
		on_click = {
			callback = function(_, minwid)
				vim.schedule(function()
					vim.api.nvim_buf_delete(minwid, { force = false })
					vim.cmd.redrawtabline()
				end)
			end,
			minwid = function(self)
				return self.bufnr
			end,
			name = "heirline_tabline_close_buffer_callback",
		},
	},
}

-- The final touch!
local TablineBufferBlock = utils.surround({ "", "" }, function(self)
	if self.is_active then
		return utils.get_highlight("TabLineSel").bg
	else
		return utils.get_highlight("TabLine").bg
	end
end, { TablineFileNameBlock, TablineCloseButton })

-- and here we go
local BufferLine = utils.make_buflist(
	TablineBufferBlock,
	{ provider = "", hl = { fg = "gray" } }, -- left truncation, optional (defaults to "<")
	{ provider = "", hl = { fg = "gray" } } -- right trunctation, also optional (defaults to ...... yep, ">")
	-- by the way, open a lot of buffers and try clicking them ;)
)

-- this is the default function used to retrieve buffers
local get_bufs = function()
	return vim.tbl_filter(function(bufnr)
		return vim.api.nvim_get_option_value("buflisted", { buf = bufnr })
	end, vim.api.nvim_list_bufs())
end

-- initialize the buflist cache
local buflist_cache = {}

-- setup an autocmd that updates the buflist_cache every time that buffers are added/removed
vim.api.nvim_create_autocmd({ "VimEnter", "UIEnter", "BufAdd", "BufDelete" }, {
	callback = function()
		vim.schedule(function()
			local buffers = get_bufs()
			for i, v in ipairs(buffers) do
				buflist_cache[i] = v
			end
			for i = #buffers + 1, #buflist_cache do
				buflist_cache[i] = nil
			end

			-- check how many buffers we have and set showtabline accordingly
			if #buflist_cache > 1 then
				vim.o.showtabline = 2 -- always
			elseif vim.o.showtabline ~= 1 then -- don't reset the option if it's already at default value
				vim.o.showtabline = 1 -- only when #tabpages > 1
			end
		end)
	end,
})

local BufferLine = utils.make_buflist(
	TablineBufferBlock,
	{ provider = " ", hl = { fg = "gray" } },
	{ provider = " ", hl = { fg = "gray" } },
	-- out buf_func simply returns the buflist_cache
	function()
		return buflist_cache
	end,
	-- no cache, as we're handling everything ourselves
	false
)

FileNameBlock = utils.insert(FileNameBlock, utils.insert(FileNameModifer, FileName), FileFlags, { provider = "%<" })

local StatusLine = {
	ViMode,
	Space,
	Space,
	Git,
	Space,
	Space,
	FileNameBlock,
	Align,
	LSPActive,
	Space,
	FileType,
	Space,
	Ruler,
	Space,
	ScrollBar,
}

local TabLine = { BufferLine }

require("heirline").setup({
	statusline = StatusLine,
	tabline = TabLine,
	opts = {
		colors = setup_colours,
	},
})

vim.o.showtabline = 2
vim.cmd([[au FileType * if index(['wipe', 'delete'], &bufhidden) >= 0 | set nobuflisted | endif]])