[Eluna] Profession NPC

local ProfessionNPC = {}
ProfessionNPC.Entry = 10001001

ProfessionNPC.prof = {
    [1] = {{171, 51303, "Alchemy", "201001, 201002, 201003", 51304},
           {164, 51298, "Blacksmithing", "201004, 201005, 201006", 51300},
           {333, 51312, "Enchanting", "201009, 201010, 201011", 51313},
           {202, 51305, "Engineering", "201012, 201013, 201014", 51306},
           {182, 50301, "Herbalism", "201018, 201019, 201020", 50300},
           {755, 51310, "Jewelcrafting", "201024, 201025, 201026", 51311},
           {165, 51301, "Leatherworking", "201027, 201028, 201029", 51302},
           {186, 50309, "Mining", "201033, 201034, 201035", 50310},
           {393, 50307, "Skinning", "201036, 201037, 201038", 50305},
           {197, 51308, "Tailoring", "201039, 201040, 201041", 51309}},

    [2] = {{356, 51293, "Fishing", "202001, 202002, 202003", 51294},
           {185, 51295, "Cooking", "202004, 202005, 202006", 51296},
           {129, 50299, "First Aid", "202007, 202008, 202009", 45542}}
}

function ProfessionNPC.LoadCache()
    for _, p in ipairs(ProfessionNPC.prof) do
        for k, v in ipairs(p) do
            local skill, spell, name, profrefs = table.unpack(v)
            local q = WorldDBQuery("SELECT SpellID FROM npc_trainer WHERE ID in(" .. profrefs .. ")")
            v[4] = {};
            local recipes = v[4]
            if q then
                repeat
                    table.insert(recipes, q:GetUInt32(0))
                until not q:NextRow()
            end
        end
    end
    PrintInfo(
        "[Profession NPC]: Cache initialized. Loaded " .. #ProfessionNPC.prof[1] + #ProfessionNPC.prof[2] ..
            " professions.")
end

function ProfessionNPC.OnGossip(event, player, unit)
    player:GossipClearMenu()
    player:GossipMenuAddItem(3, "Primary Professions", 0, 1)
    player:GossipMenuAddItem(3, "Secondary Professions", 0, 2)
    player:GossipSendMenu(100, unit)
end

function ProfessionNPC.OnSelect(event, player, unit, id, intid, code)
    player:GossipClearMenu()
    if id == 0 then
        if intid == 1 or intid == 2 then
            for k, v in ipairs(ProfessionNPC.prof[intid]) do
                local skill, spell, name, recipes = table.unpack(v)
                if not player:HasSkill(skill) then
                    player:GossipMenuAddItem(3, "Learn " .. name, 3 + intid, k)
                else
                    player:GossipMenuAddItem(3, "Unlearn " .. name, 3 + intid, k)
                end
            end
            player:GossipMenuAddItem(7, "Back..", 0, 3)
            player:GossipSendMenu(100, unit)
            return
        elseif intid == 3 then
            On_Gossip(event, player, unit)
            return
        end
    end

    if id == 4 or id == 5 then
        id = id - 3

        local skill, spell, name, recipes, unlearnspell = table.unpack(ProfessionNPC.prof[id][intid])
        if not player:HasSkill(skill) then
            -- if id is primary prof and we cant learn more
            if id == 1 and player:GetUInt32Value(PLAYER_CHARACTER_POINTS2) <= 0 then
                player:SendNotification("You can not learn more primary professions!")
                On_Select(event, player, unit, 0, 3)
                return
            else
                player:CastSpell(player, spell)
                player:AdvanceSkill(skill, player:GetPureMaxSkillValue(skill))
                for k, v in ipairs(recipes) do
                    if not player:HasSpell(v) then
                        player:LearnSpell(v)
                    end
                end
            end
            if id == 1 then
                player:SetUInt32Value(PLAYER_CHARACTER_POINTS2, player:GetUInt32Value(PLAYER_CHARACTER_POINTS2) - 1)
            end
        else
            for k, v in ipairs(recipes) do
                if player:HasSpell(v) then
                    player:RemoveAura(v)
                    player:RemoveSpell(v)
                end
            end
            player:RemoveAura(spell)
            player:RemoveAura(unlearnspell)
            player:RemoveSpell(spell)
            player:RemoveSpell(unlearnspell)
            player:SetSkill(skill, 0, 0, 0)
            if id == 1 then
                player:SetUInt32Value(PLAYER_CHARACTER_POINTS2, player:GetUInt32Value(PLAYER_CHARACTER_POINTS2) + 1)
            end
        end

        On_Select(event, player, unit, 0, id)
        return
    end

    player:GossipComplete()
end

ProfessionNPC.LoadCache()

RegisterCreatureGossipEvent(ProfessionNPC.Entry, 1, ProfessionNPC.OnGossip)
RegisterCreatureGossipEvent(ProfessionNPC.Entry, 2, ProfessionNPC.OnSelect)