fix_rat_climb_teleport

-- Fix for rats skipping climb animations, which visually becomes a teleport (TP) and allows the rats to instantly attack players when they should finish climbing up ledges first.
-- This may also fix gutter runners from doing instant pounce after skipping climb animations. Note that instant pounce is a game design, but now with the fix they will have to wait until the end of the climb animations to do instant pounce.
-- This doesn't fix visual TP for clients due to lag or rat position desync.
--
-- Xq & VernonKun 2020
--
-- This adjustment is intended to work with QoL modpack
-- To "install" copy the file to "steamapps\common\Warhammer End Times Vermintide\binaries\mods\patch"

local mod_name = "fix_rat_climb_teleport"


local clear_jump_climb_finished = function(blackboard)
    -- EchoConsole("jump_climb_finished set to nil")
    blackboard.jump_climb_finished = nil
    return
end

local set_jump_climb_finished = function(blackboard)
    -- EchoConsole("jump_climb_finished set to true")
    blackboard.jump_climb_finished = true
    return
end

local JUMP_CLIMB_FINISHED_DELAY = 0.3   -- seconds
local JUMP_CLIMB_FAILSAFE_TIME  = 4     -- seconds
local mod_climb_data = {}

Mods.hook.set(mod_name , "BTClimbAction.enter", function(func, self, unit, blackboard, t)
    local ret = func(self, unit, blackboard, t)

    --From testing: This fixes climb TP for single climb right after a fall; set the flag to nil if climb action hasn't start yet
    clear_jump_climb_finished(blackboard)

    mod_climb_data[unit] = nil

    return ret
end)

Mods.hook.set(mod_name , "BTClimbAction.run", function(func, self, unit, blackboard, t, dt)

    if not mod_climb_data[unit] then
        mod_climb_data[unit] =
        {
            climb_start_time    = nil,
            last_climb_state    = "",
            last_climb_state_1  = "",
        }
    end

    --From testing: This fixes climb TP for double climb; set the flag to nil if climb animation hasn't start yet
    if blackboard.climb_state ==  "moving_to_to_entrance" and blackboard.jump_climb_finished then
        clear_jump_climb_finished(blackboard)
    end

    --This marks the beginning of the climb animation (could be off by 1-2 frames)
    if blackboard.climb_state == "waiting_for_finished_climb_anim" and mod_climb_data[unit].last_climb_state_1 == "moving_to_to_entrance" then
        mod_climb_data[unit].climb_start_time = t
    end

    local climb_started     = mod_climb_data[unit].climb_start_time
    local climb_duration    = climb_started and t - climb_started

    --Fix for rat potentially getting stuck in the climb loop, but it doesn't happen in testing so far
    if climb_started and climb_duration > JUMP_CLIMB_FAILSAFE_TIME then
        -- EchoConsole("stuck in climb loop:" .. tostring(unit))
        set_jump_climb_finished(blackboard)
    end

    --From testing: This fixes climb TP for triple climb (or more?); set the flag to nil if it set to true too early (i.e. within 0.3 second) because of previously unfinished climb animations
    if climb_started and blackboard.climb_state == "waiting_for_finished_climb_anim" and blackboard.jump_climb_finished then
        -- EchoConsole(climb_duration)
        if climb_duration < JUMP_CLIMB_FINISHED_DELAY then
            -- EchoConsole("bugged climb found")
            clear_jump_climb_finished(blackboard)
        else
            mod_climb_data[unit].climb_start_time = nil
        end
    end

    local ret = func(self, unit, blackboard, t, dt)

    mod_climb_data[unit].last_climb_state_1 = mod_climb_data[unit].last_climb_state
    mod_climb_data[unit].last_climb_state = blackboard.climb_state

    --Clear data for dead rats
    for loop_unit,_ in pairs(mod_climb_data) do
        if not Unit.alive(loop_unit) then
            mod_climb_data[loop_unit] = nil
        end
    end

    return ret
end)

-- Mods.hook.set(mod_name , "BTClimbAction.leave", function(func, self, unit, blackboard, t)
    -- if mod_climb_data[unit] then
        -- mod_climb_data[unit].climb_start_time = nil
    -- end

    -- func(self, unit, blackboard, t)
-- end)