Hilbish/nature/greenhouse.lua

56 lines
1.4 KiB
Lua

-- Greenhouse is a simple text scrolling handler for terminal programs.
-- The idea is that it can be set a region to do its scrolling and paging
-- job and then the user can draw whatever outside it.
-- This reduces code duplication for the message viewer
-- and flowerbook.
local ansikit = require 'ansikit'
local terminal = require 'terminal'
local Object = require 'nature.object'
local Greenhouse = Object:extend()
function Greenhouse:new(sink)
local size = terminal.size()
self.region = size
self.start = 1
self.offset = 1
self.sink = sink
return self
end
function Greenhouse:setText(text)
self.lines = string.split(text, '\n')
end
function Greenhouse:draw()
self.sink:write(ansikit.getCSI(self.start .. ';1', 'H'))
for i = self.offset, self.offset + (self.region.height - self.start) - 1 do
self.sink:write(ansikit.getCSI(2, 'K'))
self.sink:writeln('\r' .. self.lines[i]:gsub('\t', ' '):sub(0, self.region.width - 2))
end
self.sink:write '\r'
end
function Greenhouse:scroll(direction)
local oldOffset = self.offset
if direction == 'down' then
self.offset = math.min(self.offset + 1, #self.lines)
elseif direction == 'up' then
self.offset = math.max(self.offset - 1, 1)
end
if self.offset ~= oldOffset then self:draw() end
end
function Greenhouse:update()
local size = terminal.size()
self.region = size
self:draw()
end
return Greenhouse