MultiPusher.lua

Prime_Punchmech.PathSize = INT_MAX
Prime_Punchmech.Damage = 1


-- statemachine for the conga
local Tracked = {}
local ST_ACTIVE = 0 -- in the conga
local ST_DROPPED = 1 -- fell into a hole
local ST_PUSHED = 2 -- run into an immovable obstacle, acts as an immovable obstacle itself now
local ST_PAUSED = 3 -- temporarily paused until the conga catches up

function Prime_Punchmech:GetSkillEffect(p1, p2)
	  local ret = SkillEffect()
    local dir = GetDirection(p2 - p1)
    local dirv = DIR_VECTORS[dir]
    
    local final_state = Tracked:New(p1, dirv):GetPositions(self.PathSize)

    for i = #final_state, 1, -1 do
        local p = final_state[i]
        DoAction(p, ret)

    end
    for i = 0, p1:Manhattan(final_state[1].pos)-1 do
        ret:AddBounce(p1 + DIR_VECTORS[dir]*i, -3)
        local damage = SpaceDamage(p1 + DIR_VECTORS[dir]*i, 0)
        damage.sItem = "Item_Mine"
        damage.sAnimation = "exploout0_"..(dir)%4
        ret:AddDamage(damage)
        ret:AddDelay(0.06)
    end
    for _, p in ipairs(final_state) do
		ret:AddBounce(p.pos, -5)
        ret:AddEmitter(p.pos, "Emitter_Burst")
    end
    for _, p in ipairs(final_state.obstacles) do
        ret:AddBounce(p, -6)
        local s = SpaceDamage(p, 1)
        s.sScript = "this is a test"
        ret:AddDamage(s)
    end

    ret:AddBoardShake(0.5)
    ret:AddSound("/impact/generic/explosion")
    return ret
end
function DoAction(p, ret)
    if p.state == ST_DROPPED then
        -- this abuses a bug in the preview code
        -- the preview shows the unit dieing from DAMAGE_DEATH, the execution shows the unit diving charging to its death
        ret:AddCharge(p.path, NO_DELAY)
        local damage = SpaceDamage(p.orig_pos, DAMAGE_DEATH)
        ret:AddDamage(damage)
    else
        -- we do the damage at orig_pos because WEIRD THINGS happen to the preview if we damage at pos.
        -- this sucks because fires and smoke icons are visible when we suppress them
        local damage = SpaceDamage(p.orig_pos, 1)
        damage.sImageMark = "combat/arrow_hit.png"
        if not Board:IsFire(p.orig_pos) then
            damage.iFire = EFFECT_REMOVE
        end
        if not Board:IsSmoke(p.orig_pos) then
            damage.iSmoke = EFFECT_REMOVE
        end
        damage.iTerrain = Board:GetTerrain(p.orig_pos)
        ret:AddDamage(damage)
        ret:AddCharge(p.path, NO_DELAY)
    end
end


function Tracked:GetPositions(left)
    while left > 0 and not self:Done() do
        self:Setup()
        for i = #self, 1, -1 do
            local pawn = self[i]

            if self:Interacts(pawn) then
                local next_pos = pawn.pos + self.dirv
                local succ =  self:GetKnown(next_pos)
                local next_pawn = self:GetUnknown(next_pos)
                local invalid_terr = self:CheckTerrain(pawn.pathprof, next_pos)
                if succ then
                    if succ.state == ST_PAUSED then
                        break
                    else
                        pawn.state = ST_PUSHED
                    end
                elseif next_pawn then
                    break
                elseif invalid_terr == TERR_COLLISION then
                    pawn.state = ST_PUSHED
                elseif invalid_terr == TERR_DROPPED then
                    pawn.state = ST_DROPPED
                end
                if pawn.state ~= ST_PUSHED then
                    pawn.pos = next_pos
                    pawn.path:push_back(next_pos)
                end
                if pawn.state == ST_DROPPED then
                    break
                end
            end
            if i == 1 then
                left = left - 1
            end
        end
    end
    return self
end

Tracked.__index = Tracked
function Tracked:New(p0, dirv)
    local o = {}
    setmetatable(o, self)
    o[1] = mkMarker(Board:GetPawn(p0))
    o.obstacles = {}
    o.dirv = dirv
    return o
end
function Tracked:Interacts(p)
    return p.state == ST_ACTIVE-- and (self:Alive(p) or p.id == self[1].id)
end
function Tracked:Alive(p)
    return (p.state ~= ST_DROPPED) and not p.dead
end
function Tracked:Done()
    local pred = function(p)
        return not self:Interacts(p)
    end
    local all_stopped = all(self,  pred)
    return all_stopped or self:CheckTerrain(self[1].pathprof, self[1].pos + self.dirv)
end
function Tracked:GetKnown(p)
    return findBy(self, function(x) return (x.pos == p) and self:Alive(x) end)
end
function Tracked:GetUnknown(p)
    local board_pawn = Board:GetPawn(p)
    return board_pawn and self:Unknown(board_pawn) and board_pawn
end
function Tracked:Unknown(pawn)
    local id = pawn:GetId()
    return all(self, function(p) return p.id ~= id end)
end
function Tracked:Get(p)
    local r = self:GetKnown(p) 
    if r then
        return r
    end
    r = self:GetUnknown(p)
    if r then
        r = mkMarker(r)
        self[#self+1] = r
        return r
    end
    return nil
end

-- called whenever the conga changes
function Tracked:Setup()
    for _,v in ipairs(self) do
        if v.state == ST_ACTIVE then
            v.state = ST_PAUSED
        end
    end

    local current = self[1]
    while current do
        if current.state == ST_PAUSED then
            current.state = ST_ACTIVE
        end
        current = self:Get(current.pos + self.dirv)
    end
end

function all(ls, pred)
    for _, y in ipairs(ls) do
        if not pred(y) then
            return false
        end
    end
    return true
end
function findBy(ls, pred) 
    for _, y in ipairs(ls) do
        if pred(y) then
            return y
        end
    end
    return nil
end

function mkMarker(pawn)
    local list = PointList()
    local pos = pawn:GetSpace()
    list:push_back(pos)
    local state = pawn:IsGuarding() and ST_PUSHED or ST_ACTIVE
    local dead = pawn:GetHealth() <= 1
    -- TODO: don't hardcode 1 damage
    local o = { pos = pos, dead =  dead,  orig_pos = pos, id = pawn:GetId(), pathprof = pawn:GetPathProf(), state = state, path = list}
    return o
end


TERR_COLLISION = 1
TERR_DROPPED = 2
-- for some reason these are missing lua side
local PATH_FLIER = 1
local PATH_LEAPER = 6
INVALID_TERRAINS =
    { [PATH_FLIER] = -- 1
        { [TERRAIN_BUILDING] = TERR_COLLISION
        , [TERRAIN_MOUNTAIN] = TERR_COLLISION
        }
    , [PATH_GROUND] = -- 0
        { [TERRAIN_BUILDING] = TERR_COLLISION
        , [TERRAIN_MOUNTAIN] = TERR_COLLISION
        , [TERRAIN_ACID] = TERR_DROPPED
        , [TERRAIN_HOLE] = TERR_DROPPED
        , [TERRAIN_LAVA] = TERR_DROPPED
        , [TERRAIN_WATER] = TERR_DROPPED
        }
    , [PATH_LEAPER] = -- 6
        { [TERRAIN_BUILDING] = TERR_COLLISION
        , [TERRAIN_MOUNTAIN] = TERR_COLLISION
        , [TERRAIN_ACID] = TERR_DROPPED
        , [TERRAIN_HOLE] = TERR_DROPPED
        , [TERRAIN_LAVA] = TERR_DROPPED
        , [TERRAIN_WATER] = TERR_DROPPED
        }
    , [PATH_MASSIVE] = -- 2
        { [TERRAIN_BUILDING] = TERR_COLLISION
        , [TERRAIN_MOUNTAIN] = TERR_COLLISION
        , [TERRAIN_HOLE]     = TERR_COLLISION
        }
    , [PATH_PHASING] = {} -- 9
    , [PATH_PROJECTILE] = -- 3
        { [TERRAIN_BUILDING] = TERR_COLLISION
        , [TERRAIN_MOUNTAIN] = TERR_COLLISION
        }
    , [PATH_ROADRUNNER] = -- 4
        { [TERRAIN_BUILDING] = TERR_COLLISION
        , [TERRAIN_MOUNTAIN] = TERR_COLLISION
        , [TERRAIN_ACID] = TERR_DROPPED
        , [TERRAIN_HOLE] = TERR_DROPPED
        , [TERRAIN_LAVA] = TERR_DROPPED
        , [TERRAIN_WATER] = TERR_DROPPED
        }
    }

function Tracked:CheckTerrain(path, pos)
    local result = InvalidTerrain(path, pos)
    if result == TERR_COLLISION then
        self.obstacles[#self.obstacles+1] = pos
    end
    return result
end
function InvalidTerrain(pathtype, pos)
    local pathtype = pathtype % 16

    if not Board:IsValid(pos) then
        return TERR_COLLISION
    end
    local table = INVALID_TERRAINS[pathtype] 
    if not table then
        -- log.error("invalid pathtype: " .. pathtype .. "! ")
        table = INVALID_TERRAINS[PATH_GROUND]
    end
    local terr = Board:GetTerrain(pos)
    return table[terr]
end