Sub-100 line browser using luakit

gistfile1.lua

#!/usr/bin/luakit -c 
--------------------------------------------------------------------
-- 2011 (C) Mason Larobina <mason.larobina@gmail.com>             --
-- Browser in under 128 lines of code? (my attempt)               --
-- See: http://lateral.netmanagers.com.ar/weblog/posts/BB948.html --
--------------------------------------------------------------------

local homepage = "http://luakit.org/"

-- Create the browser window
local win,    vbox = widget{type="window"}, widget{type="vbox"}
local urlbar, view = widget{type="entry"},  widget{type="webview"}
vbox:pack_start(view, true, true, 0)
vbox:pack_start(urlbar, false, false, 0)
win:set_child(vbox)
win:show()
view:focus()

-- Quit on window destroy
win:add_signal("destroy", luakit.quit)

-- On webview navigate update the address bar
view:add_signal("property::uri", function () urlbar.text = view.uri end)

function smart_go(uri)
    if uri == "about:blank" or string.match(uri, "^https?://") 
    then view.uri = uri else view.uri = "http://google.com/search?q="..uri end
end

-- Navigate webview to url in address bar on Return press
urlbar:add_signal("activate", function () smart_go(urlbar.text) end)
urlbar:add_signal("key-press", function (_, _, key)
    if key == "Escape" then view:focus() return true end end)

function has(table, item)
    for _, v in ipairs(table) do 
        if v == item then return true end
    end
end

function scroll(vert, value) 
    local c,m=(vert and view.get_scroll_vert or view.get_scroll_horiz)(view)
    if type(value) == "string" then value = c + value -- relative
    elseif value == -1 then value = m end -- bottom of page
    (vert and view.set_scroll_vert or view.set_scroll_horiz)(view, value)
end

function zoom(value) 
    local zoom = view:get_property("zoom-level")
    if type(value) == "string" then value = zoom + value end
    view:set_property("zoom-level", value)
end

-- Set initial mode (this is going to be a modal browser)
local mode = "normal"

-- Hardcoded bindings
view:add_signal("key-press", function (_, mods, key)
    -- Auto remove Shift
    local Control, Alt, Shift = has(mods, "Control"), has(mods, "Mod1"), false
    if has(mods, "Shift") then 
        if #key == 1 then key = string.upper(key) else Shift = true end 
    end

    -- Return to normal mode on escape
    if key == "Escape" or (Control and key == "[") then
        mode = "normal" 
        return true 
    end

    -- Capture key presses in insert mode
    if mode == "insert" then return false end

    if mode == "normal" and not Control and not Shift and not Alt then
        if     key == "h" then scroll(false, "-40")
        elseif key == "j" then scroll(true,  "+40")
        elseif key == "k" then scroll(true,  "-40")
        elseif key == "l" then scroll(false, "+40")
        elseif key == "G" then scroll(true, -1)
        elseif key == "g" then mode = "g" -- Extended go
        elseif key == "0" then scroll(false, 0)
        elseif key == "$" then scroll(false, -1)
        elseif key == "r" then view:reload()
        elseif key == "p" then smart_go(luakit.get_selection() or "about:blank")
        elseif key == "H" then view:go_back(1)
        elseif key == "L" then view:go_forward(1)
        elseif key == "z" then mode = "z" -- Zoom
        elseif key == "d" or key == "D" then luakit.quit()
        elseif key == "o" then urlbar:focus()
        end

    elseif mode == "normal" and Control and not Shift and not Alt then
        if key == "c" then view:stop() end

    elseif mode == "g" and not Control and not Shift and not Alt then
        if     key == "h" then view.uri = homepage
        elseif key == "g" then scroll(true, 0)
        end
        mode = "" -- ignore further keys

    elseif mode == "z" and not Control and not Shift and not Alt then
        if     key == "i" then zoom("+0.1")
        elseif key == "o" then zoom("-0.1")
        elseif key == "z" then zoom(1.0)
        end 
        mode = "" -- ignore further keys
    end
    return true
end) 

-- Go to homepage
view.uri = homepage