local Ansi   = require('opus.ansi')
local SHA    = require('opus.crypto.sha2')
local UI     = require('opus.ui')
local Util   = require('opus.util')

local fs         = _G.fs
local http       = _G.http
local multishell = _ENV.multishell
local os         = _G.os
local shell      = _ENV.shell
local colors     = _G.colors

local REGISTRY_DIR = 'usr/.registry'

--                                           FIX SOMEDAY
local function registerApp(app, key)
	app.key = SHA.compute(key)
	Util.writeTable(fs.combine(REGISTRY_DIR, app.key), app)
	os.queueEvent('os_register_app')
end

local function unregisterApp(key)
	local filename = fs.combine(REGISTRY_DIR, SHA.compute(key))
	if fs.exists(filename) then
		fs.delete(filename)
		os.queueEvent('os_register_app')
	end
end

multishell.setTitle(multishell.getCurrent(), 'App Store')
UI:configure('Appstore', ...)

local APP_DIR = 'usr/apps'

local source = {
	text = "STD Default",
	event = 'source',
	url = "https://github.com/LDDestroier/STD-GUI/raw/master/list.lua",
}

shell.setDir(APP_DIR)

local function downloadApp(app)
	local h

	if type(app.url) == "table" then
		h = contextualGet(app.url[1])
	else
		h = http.get(app.url)
	end

	if h then
		local contents = h.readAll()
		h:close()
		return contents
	end
end

local function runApp(app, checkExists, ...)
	local env = shell.makeEnv(_ENV)
	local path, fn
	local args = { ... }

	if checkExists and fs.exists(fs.combine(APP_DIR, app.name)) then
		path = fs.combine(APP_DIR, app.name)
	else
		local program = downloadApp(app)

		fn = function()

			if not program then
				error('Failed to download')
			end

			fn = _G.loadstring(program, app.name)

			if not fn then
				error('Failed to download')
			end

			_G.setfenv(fn, env)
			fn(table.unpack(args))
		end
	end

	multishell.openTab(_ENV, {
		title = app.name,
		path = path,
		fn = fn,
		focused = true,
	})

	return true, 'Running program'
end

local installApp = function(app)

	local program = downloadApp(app)
	if not program then
		return false, "Failed to download"
	end

	local fullPath = fs.combine(APP_DIR, app.name)
	Util.writeFile(fullPath, program)
	return true, 'Installed as ' .. fullPath
end

local viewApp = function(app)

	local program = downloadApp(app)
	if not program then
		return false, "Failed to download"
	end

	Util.writeFile('/.source', program)
	shell.openForegroundTab('edit /.source')
	fs.delete('/.source')
	return true
end

local getSourceListing = function()
	local contents = http.get(source.url)
	if contents then

		local fn = _G.loadstring(contents.readAll(), source.text)
		contents.close()

		local env = { std = { } }
		setmetatable(env, { __index = _G })
		_G.setfenv(fn, env)
		fn()

		if env.contextualGet then
			contextualGet = env.contextualGet
		end

		source.storeURLs = env.std.storeURLs
		source.storeCatagoryNames = env.std.storeCatagoryNames

		if source.storeURLs and source.storeCatagoryNames then
			for k,v in pairs(source.storeURLs) do
				if source.generateName then
					v.name = v.title:match('(%w+)')
					if not v.name or #v.name == 0 then
						v.name = tostring(k)
					else
						v.name = v.name:lower()
					end
				else
					v.name = k
				end
				v.categoryName = source.storeCatagoryNames[v.catagory]
				v.ltitle = v.title:lower()
			end
		end
	end
end

getSourceListing()

if not source.storeURLs then
	error('Unable to download application list')
end

local buttons = { }
for k,v in Util.spairs(source.storeCatagoryNames,
			function(a, b) return a:lower() < b:lower() end) do

	if v ~= 'Operating System' then
		table.insert(buttons, {
			text = v,
			event = 'category',
			index = k,
		})
	end
end
source.index, source.name = Util.first(source.storeCatagoryNames)

local appPage = UI.Page {
	menuBar = UI.MenuBar {
		buttons = {
			{ text = '\027',    event = 'back'    },
			{ text = 'Install', event = 'install' },
			{ text = 'Run',     event = 'run'     },
			{ text = 'View',    event = 'view'    },
			{ text = 'Remove',  event = 'uninstall', name = 'removeButton' },
		},
	},
	container = UI.Window {
		x = 2, y = 3, ex = -2, ey = -3,
		viewport = UI.Viewport(),
	},
	notification = UI.Notification(),
	accelerators = {
		[ 'control-q' ] = 'back',
		backspace = 'back',
	},
}

function appPage.container.viewport:draw()
	local app = self.parent.parent.app
	local str = string.format(
		'%s \nBy: %s \nCategory: %s\nFile name: %s\n\n%s',
		Ansi.yellow .. app.title .. Ansi.reset,
		app.creator,
		app.categoryName, app.name,
		Ansi.yellow .. app.description .. Ansi.reset)

	self:clear()
	self:print(str)

	if appPage.notification.enabled then
		appPage.notification:draw()
	end
end

function appPage:enable(app)
	self.source = source
	self.app = app
	UI.Page.enable(self)

	self.container.viewport:setScrollPosition(0)
	if fs.exists(fs.combine(APP_DIR, app.name)) then
		self.menuBar.removeButton:enable('Remove')
	else
		self.menuBar.removeButton:disable('Remove')
	end
end

function appPage:eventHandler(event)
	if event.type == 'back' then
		UI:setPreviousPage()

	elseif event.type == 'run' then
		self.notification:info('Running program', 3)
		self:sync()
		runApp(self.app, true)

	elseif event.type == 'view' then
		self.notification:info('Downloading program', 3)
		self:sync()
		viewApp(self.app)

	elseif event.type == 'uninstall' then
		if self.app.runOnly then
			runApp(self.app, false, 'uninstall')
		else
			fs.delete(fs.combine(APP_DIR, self.app.name))
			self.notification:success("Uninstalled " .. self.app.name, 3)
			self:focusFirst(self)
			self.menuBar.removeButton:disable('Remove')
			self.menuBar:draw()

			unregisterApp(self.app.creator .. '.' .. self.app.name)
		end

	elseif event.type == 'install' then
		self.notification:info("Installing", 3)
		self:sync()
		local s, m
		if self.app.runOnly then
			s,m = runApp(self.app, false)
		else
			s,m = installApp(self.app)
		end
		if s then
			self.notification:success(m, 3)

			if not self.app.runOnly then
				self.menuBar.removeButton:enable('Remove')
				self.menuBar:draw()

				local category = 'Apps'
				if self.app.catagoryName == 'Game' then
					category = 'Games'
				end

				registerApp({
					run = fs.combine(APP_DIR, self.app.name),
					title = self.app.title,
					category = category,
					icon = self.app.icon,
				}, self.app.creator .. '.' .. self.app.name)
			end
		else
			self.notification:error(m, 3)
		end
	else
		return UI.Page.eventHandler(self, event)
	end
	return true
end

local categoryPage = UI.Page {
	menuBar = UI.MenuBar {
		buttons = {
			{ text = 'Category', name = 'categoryButton', dropdown = buttons },
		},
	},
	grid = UI.ScrollingGrid {
		y = 2, ey = -2,
		columns = {
			{ heading = 'Title', key = 'title' },
		},
		sortColumn = 'title',
	},
	statusBar = UI.StatusBar(),
	accelerators = {
		l = 'lua',
		[ 'control-q' ] = 'quit',
	},
	source = source,
}

function categoryPage:setCategory(name, index)
	self.grid.values = { }
	for _,v in pairs(source.storeURLs) do
		if index == 0 or index == v.catagory then
			table.insert(self.grid.values, v)
		end
	end
	self.statusBar:setStatus(string.format('%s: %s', self.source.text or '', name))
	self.grid:update()
	self.grid:setIndex(1)
end

function categoryPage.grid:sortCompare(a, b)
	return a.ltitle < b.ltitle
end

function categoryPage.grid:getRowTextColor(row, selected)
	if fs.exists(fs.combine(APP_DIR, row.name)) then
		return colors.orange
	end
	return UI.Grid:getRowTextColor(row, selected)
end

function categoryPage:eventHandler(event)
	if event.type == 'grid_select' or event.type == 'select' then
		UI:setPage(appPage, self.grid:getSelected())

	elseif event.type == 'category' then
		self:setCategory(event.button.text, event.button.index)
		self:setFocus(self.grid)
		self:draw()

	elseif event.type == 'source' then
		self:setFocus(self.grid)
		self:setSource(event.button)
		self:draw()

	elseif event.type == 'quit' then
		UI:quit()

	else
		return UI.Page.eventHandler(self, event)
	end
	return true
end

print("Retrieving catalog list")
categoryPage:setCategory(source.name, source.index)

UI:setPage(categoryPage)
UI:start()