local ColliderManager = {}

local private =
{
    _activeDic = {},
    _prepareDic = {},
    _activeList = {},   --用来遍历的List，之前遍历的_activeDic会导致不一致，改为遍历List 2022年6月7日 HYW
}

local totalID = 0
local ConstZero = FP.Const.Zero
local ConstNegOne = FP.Const.NegOne
local FP_IsDistanceSqrGreater = FP.V2.IsDistanceSqrGreater
local FP_IsInRectRange = FP.V2.IsInRectRange

local function CheckAllCover()
    return true
end

local function CheckCircle(collider, entity)
    local pos = entity.components.move.LogicPos
    return not FP_IsDistanceSqrGreater(pos, collider.pos, collider.radiusSqr)
end

local function CheckRect(collider, entity)
    local pos = entity.components.move.LogicPos
    return FP_IsInRectRange(pos,collider.pos,collider.dir,collider.length,collider.width)
end

function ColliderManager.CreateRectCollider(pos,dir,length,width)
    if length <= ConstZero or width <= ConstZero then
        return
    end

    totalID = totalID + 1
    private._prepareDic[totalID] = {
        pos = pos, dir = dir, length = length, width = width,
        inColliderList = {}, checkFunc = CheckRect, ID = totalID
    }
    return totalID
end

function ColliderManager.CreateCircleCollider(pos,radiusSqr)
    if radiusSqr == ConstNegOne then
        totalID = totalID + 1
        private._prepareDic[totalID] = { inColliderList = {}, checkFunc = CheckAllCover, ID = totalID}
        return totalID
    elseif radiusSqr > ConstZero then
        totalID = totalID + 1
        private._prepareDic[totalID] = {pos = pos, radiusSqr = radiusSqr, inColliderList = {}, checkFunc = CheckCircle, ID = totalID}
        return totalID
    end
end

function ColliderManager.ActiveCollider(id,iter,iterOwner)
    local collider = private._prepareDic[id]
    if collider then
        private._prepareDic[id] = nil
        if private._activeDic[id] == nil then
            table.insert(private._activeList, collider)
        end
        private._activeDic[id] = collider
        collider.iter = iter
        collider.iterOwner = iterOwner
    end
end

function ColliderManager.DeActiveCollider(id)
    local collider = private._activeDic[id]
    if collider then
        private._activeDic[id] = nil
        for i,v in ipairs(private._activeList) do
            if v.ID == id then
                table.remove(private._activeList, i)
                break
            end
        end
        private._prepareDic[id] = collider
        private.OnDisableCollider(collider, LuaConst.EColliderExitReason.DEACTIVE)
    end
end

function ColliderManager.DestroyCollider(id)
    local collider = private._activeDic[id]
    private._activeDic[id] = nil
    for i,v in ipairs(private._activeList) do
        if v.ID == id then
            table.remove(private._activeList, i)
            break
        end
    end
    private._prepareDic[id] = nil
    if collider then
        private.OnDisableCollider(collider, LuaConst.EColliderExitReason.DESTROY)
        collider.isDestroyed = true
    end
end

function ColliderManager.UpdatePos(id , pos)
    local collider = private._activeDic[id]
    if collider then
        collider.pos:Reset(pos)
    end
end

function ColliderManager.AddEnterEvent(id,func,self)
    local collider = private._prepareDic[id] or private._activeDic[id]
    if collider then
        collider.enterFunc = func
        collider.enterOwner = self
    end
end

function ColliderManager.AddStayEvent(id,func,self)
    local collider = private._prepareDic[id] or private._activeDic[id]
    if collider then
        collider.stayFunc = func
        collider.stayOwner = self
    end
end

function ColliderManager.AddExitEvent(id,func,self)
    local collider = private._prepareDic[id] or private._activeDic[id]
    if collider then
        collider.exitFunc = func
        collider.exitOwner = self
    end
end

function ColliderManager.OnUpdate()
    --for k, collider in pairs(private._activeDic) do --old  遍历字典，会导致不一致
    for i,collider in ipairs(private._activeList) do   --new 遍历List
        private.HandleCollider(collider)
    end
end

function ColliderManager.Clear()
    totalID = 0
    table.clear(private._activeDic)
    table.clear(private._activeList)
    table.clear(private._prepareDic)
end

function ColliderManager.CheckInCollider(id, entity)
    local collider = private._activeDic[id]
    if collider then
        for _, v in ipairs(collider.inColliderList) do
            if v.entity == entity then
                return true
            end
        end
    end
    return false
end

function ColliderManager.GetInColliderCount(id)
    local collider = private._activeDic[id]
    if collider then
        return #collider.inColliderList
    end
    return 0
end

function private.HandleCollider(collider)
    local list = collider.inColliderList
    for _, entity in collider.iter(collider.iterOwner) do
        local info
        for i,v in ipairs(list) do
            if v.entity == entity then
                info = v
                break
            end
        end

        if collider.checkFunc(collider,entity) then
            if info then
                info.invoke = private.StayInvoke
            else
                info = { entity = entity, invoke = private.EnterInvoke}
                table.insert(list , info)
            end
        end
    end

    for i = #list, 1, -1 do
        if not collider.isDestroyed then
            local info = list[i]
            if info then
                local entity = info.entity
                if info.invoke then
                    info.invoke(collider,entity)
                    info.invoke = nil
                else
                    table.remove(list, i)
                    private.ExitInvoke(collider, entity)
                end
            --else
                --do nothing info.invoke 可能改变 list ，所以有可能包含空（最常见的情况是 private.OnDisableCollider 导致 list 被清空）
            end
        end
    end
end

function private.OnDisableCollider(collider, disableReason)
    for i,info in ipairs(collider.inColliderList) do
        if collider.exitFunc then
            if collider.exitOwner then
                collider.exitFunc(collider.exitOwner ,info.entity, disableReason)
            else
                collider.exitFunc(info.entity, disableReason)
            end
        end
    end
    table.clearArray(collider.inColliderList)
end

function private.EnterInvoke(collider, entity)
    if collider.enterFunc then
        if collider.enterOwner then
            collider.enterFunc(collider.enterOwner ,entity)
        else
            collider.enterFunc(entity)
        end
    end
end

function private.StayInvoke(collider, entity)
    if collider.stayFunc then
        if collider.stayOwner then
            collider.stayFunc(collider.stayOwner, entity)
        else
            collider.stayFunc(entity)
        end
    end
end

function private.ExitInvoke(collider, entity)
    if collider.exitFunc then
        if collider.exitOwner then
            collider.exitFunc(collider.exitOwner, entity)
        else
            collider.exitFunc(entity)
        end
    end
end

return ColliderManager