-------------------------------------------------------------------------------
---------------------------------- NAMESPACE ----------------------------------
-------------------------------------------------------------------------------

local ADDON_NAME, ns = ...
local Class = ns.Class

-------------------------------------------------------------------------------
--------------------------------- REQUIREMENT ---------------------------------
-------------------------------------------------------------------------------

--[[

Base class for all node requirements.

    text (string): Requirement text

--]]

local Requirement = Class('Requirement', nil, { text = UNKNOWN })
function Requirement:GetText() return self.text end
function Requirement:IsMet() return false end

-------------------------------------------------------------------------------
---------------------------------- CURRENCY -----------------------------------
-------------------------------------------------------------------------------

local Currency = Class('Currency', Requirement)

function Currency:Initialize(id, count)
    self.id, self.count = id, count
    self.text = string.format('{currency:%d} x%d', self.id, self.count)
end

function Currency:IsMet()
    local info = C_CurrencyInfo.GetCurrencyInfo(self.id)
    return info and info.quantity >= self.count
end

-------------------------------------------------------------------------------
------------------------------- GARRISON TALENT -------------------------------
-------------------------------------------------------------------------------

local GarrisonTalent = Class('GarrisonTalent', Requirement)

function GarrisonTalent:Initialize(id, text)
    self.id, self.text = id, text
end

function GarrisonTalent:GetText()
    local info = C_Garrison.GetTalentInfo(self.id)
    return self.text:format(info.name)
end

function GarrisonTalent:IsMet()
    local info = C_Garrison.GetTalentInfo(self.id)
    return info and info.researched
end

-------------------------------------------------------------------------------
------------------------------------ ITEM -------------------------------------
-------------------------------------------------------------------------------

local function IterateBagSlots()
    local bag, slot, slots = nil, 1, 1
    return function ()
        if bag == nil or slot == slots then
            repeat
                bag = (bag or -1) + 1
                slot = 1
                slots = GetContainerNumSlots(bag)
            until slots > 0 or bag > 4
            if bag > 4 then return end
        else
            slot = slot + 1
        end
        return bag, slot
    end
end

-------------------------------------------------------------------------------

local Item = Class('Item', Requirement)

function Item:Initialize(id, count)
    self.id, self.count = id, count
    self.text = string.format('{item:%d}', self.id)
    if self.count and self.count > 1 then
        self.text = self.text..' x'..self.count
    end
end

function Item:IsMet()
    for bag, slot in IterateBagSlots() do
        if GetContainerItemID(bag, slot) == self.id then
            if self.count and self.count > 1 then
                return select(2, GetContainerItemInfo(bag, slot)) >= self.count
            else return true end
        end
    end
    return false
end

-------------------------------------------------------------------------------
------------------------------------ SPELL ------------------------------------
-------------------------------------------------------------------------------

local Spell = Class('Spell', Requirement)

function Spell:Initialize(id)
    self.id = id
    self.text = string.format('{spell:%d}', self.id)
end

function Spell:IsMet()
    for i = 1, 255 do
        local buff = select(10, UnitAura('player', i, 'HELPFUL'))
        local debuff = select(10, UnitAura('player', i, 'HARMFUL'))
        if buff == self.id or debuff == self.id then return true end
    end
    return false
end

-------------------------------------------------------------------------------

ns.requirement = {
    Currency=Currency,
    GarrisonTalent=GarrisonTalent,
    Item=Item,
    Requirement=Requirement,
    Spell=Spell
}