local Luan = require "luan:Luan.luan"
local error = Luan.error
local stringify = Luan.stringify or error()
local pairs = Luan.pairs or error()
local ipairs = Luan.ipairs or error()
local range = Luan.range or error()
local Io = require "luan:Io.luan"
local uri = Io.uri or error()
local Number = require "luan:Number.luan"
local long = Number.long or error()
local Time = require "luan:Time.luan"
local time_now = Time.now or error()
local Table = require "luan:Table.luan"
local copy = Table.copy or error()
local sort = Table.sort or error()
local Thread = require "luan:Thread.luan"
local Lucene = require "luan:lucene/Lucene.luan"
local Shared = require "site:/lib/Shared.luan"
local compressed = Shared.compressed or error()
local Utils = require "site:/lib/Utils.luan"
local list_to_set = Utils.list_to_set or error()
local Logging = require "luan:logging/Logging.luan"
local logger = Logging.logger "Reporting"


local Reporting = {}

local dir = uri("site:/private/local/reporting")

local db = Lucene.index( dir )
Reporting.db = db

db.indexed_fields.owner = Lucene.type.string
db.indexed_fields.value = Lucene.type.string
db.indexed_fields.day = Lucene.type.long


local day = Time.period{days=1}
local days = Time.period{days=30}
local offset_from_GMT = Time.period{hours=7}

local function today()
	local today = (time_now() - offset_from_GMT) // day * day + offset_from_GMT
	return long(today)
end

local function by_count(rec1,rec2)
	return rec1.count > rec2.count
end

local limit = 20

function Reporting.get_data( query, sum_by )
	local first_day = long(today() - days)
	query = query.." +day:["..first_day.." TO *]"
	local data
	if sum_by == nil then
		data = db.search( query, 1, 1000000 )
	else
		local t = {}
		db.advanced_search( query, function(_,doc_fn,_)
			local doc = doc_fn()
			local key = doc[sum_by]
			if key == nil then
				logger.warn("missing '"..sum_by.."' in "..stringify(doc))
				return
			end
			local count = doc.count or error()
			local found = t[key]
			if found == nil then
				t[key] = {
					[sum_by] = key
					count = count
				}
			else
				found.count = found.count + count
			end
		end )
		data = {}
		for _, val in pairs(t) do
			data[#data+1] = val
		end
	end

	-- for graph
	if sum_by == nil or sum_by == "day" then
		local last_day = today()
		local first_day = last_day - days
		local map = {}
		for _, el in ipairs(data) do
			map[long(el.day)] = el.count
		end
		data = {}
		for date in range(first_day,last_day,day) do
			date = long(date)
			local count = map[date] or 0
			data[#data+1] = {date,count}
		end
		return data
	else
		sort(data,by_count)
		local t = {nil}
		local n = 0
		for _, el in ipairs(data) do
			t[#t+1] = { x=el[sum_by], y=el.count }
			n = n + 1
			if n == limit then
				break
			end
		end
		return t
	end
end

local function delete_old()
	logger.warn "delete_old"
	local expired = long( today() - Time.period{days=31} )
	db.delete( "day:[* TO "..expired.."}" )
end
-- delete_old()
Thread.schedule( delete_old, { repeating_delay=Time.period{days=1} } )


-- for ads

db.indexed_fields.ad_visit_owner_id = Lucene.type.long

local visit_period = Time.period{hours=1}
-- visit_period = Time.period{seconds=1}

function Reporting.maybe_track_visit(owner)
	local doc = db.get_document{ ad_visit_owner_id = owner.id }
	return doc == nil or doc.time + visit_period < time_now()
end

function Reporting.should_track_visit(owner)
	return db.run_in_transaction( function()
		local now = time_now()
		local doc = db.get_document{ ad_visit_owner_id = owner.id }
		if doc == nil then
			db.save{
				type = "ad_visit"
				ad_visit_owner_id = owner.id
				time = now
			}
			return true
		elseif doc.time + visit_period < now then
			doc.time = now
			db.save(doc)
			return true
		else
			return false
		end
	end )
end

function Reporting.owners_with_visits()
	local owner_ids = list_to_set{}
	local docs = db.search("type:ad_visit",1,1000000)
	for _, doc in ipairs(docs) do
		owner_ids[doc.ad_visit_owner_id] = true
	end
	return owner_ids
end

return Reporting