#! /usr/bin/env lua

-- Data extractor for http://www.pogdesign.co.uk/cat/

-- Mikael BERTHE, 2010-04-18

require "libs.shcmd"

local tvcal = { ["desc"] = "Display TV calendar" }

local tvcaldata = {}

local tvcaldata_timestamp

-- Function from PIL

local function pairsByKeys (t, f)

    local a = {}

    for n in pairs(t) do table.insert(a, n) end

    table.sort(a, f)

    local i = 0      -- iterator variable

    local iter = function ()   -- iterator function

        i = i + 1

        if a[i] == nil then return nil

        else return a[i], t[a[i]]

        end

    end

    return iter

end

local function parse_webpage (url)

    local contents = shcmd("curl "..url)

    local tabregex = '<td id="d_(%d+_%d+_%d%d%d%d)" class="t?o?day"%s*>%s*\n%s*'..

                     '<table>(.-)</table>'

    for day, tab in string.gmatch(contents, tabregex) do

        local epregex

        local d, m, y = day:match("^(%d+)_(%d+)_(%d%d%d%d)$")

        day = string.format("%04d-%02d-%02d", y, m, d)

        epregex = '<td><a id="[^"]+" href="[^"]+" class="eplink%s*"%s*>([^<]+)</a>'

        epregex = epregex .. '<span class="seasep"%s*></span><br />'

        epregex = epregex .. '<span class="seasep"%s*>([^<]+)</span>[%s\n]*</td>'

        local shows = {}

        for name, ep in string.gmatch(tab, epregex) do

            name = name:gsub(""", "\""):gsub("&", "&")

            name = name:gsub("&lt;", "<"):gsub("&gt;", ">")

            name = name:gsub("'", "'")

            local obj = {

                ["name"] = name,

                ["ep"] = ep

                }

            table.insert(shows, obj)

        end

        tvcaldata[day] = shows

    end

    tvcaldata_timestamp = os.date("%F")

    return true

end

local function tvcal_by_date (d)

    if not tvcaldata[d] then

        return "No episode found for this date ("..d..")"

    end

    local r = "Shows on " .. d .. ":\n"

    for i,j in ipairs(tvcaldata[d]) do

        r = r .. j.name .. " (" ..j.ep .. ")\n"

    end

    r = r:gsub("\n+$", "")

    return r

end

    local r = ""

    name = name:lower()

    for day, obj in pairsByKeys(tvcaldata) do

        for i,j in ipairs(obj) do

                r = r .. day .. "\t" .. j.name .. " (" ..j.ep .. ")\n"

            end

        end

    end

    if r == "" then

    end

    r = r:gsub("\n+$", "")

end

function tvcal.cmd (arg)

    if not tvcaldata_timestamp or tvcaldata_timestamp ~= os.date("%F") then

        tvcaldata = {} -- Empty the previous list

        local r, err = parse_webpage("http://www.pogdesign.co.uk/cat/")

        if not r then return nil, err end

        -- Fetch next month as well...

        local m = tonumber(os.date("%m"))+1

        local y = os.date("%Y")

        if m > 12 then m = 1; y = y + 1; end

        parse_webpage("http://www.pogdesign.co.uk/cat/"..m.."-"..y)

    end

    if not arg or arg == "today" then

        arg = os.date("%F")

    elseif arg == "tomorrow" then

        arg = os.date("%F", os.date("%s")+86400)

    elseif arg:match("^%+%d+$") then

        local n = tonumber(arg:match("^%+(%d+)$"))

        if n < 60 then

            arg = os.date("%F", os.date("%s")+86400*n)

        end

    end

    if arg:match("^%d%d%d%d%-%d%d%-%d%d$") then

        return tvcal_by_date(arg)

    end

end

mcbot_register_command("tvcal", tvcal)