-- DOCS - General

-- game.register(gameid) - nil
-- game.update() - nil
-- game.render() - nil

-- DOCS - Variables

-- variables.get(variableName) - nil
-- variables.set(variableName, value) - nil
-- variables.increment(variableName, by) - nil
-- variables.decrement(variableName, by) - nil

-- DOCS - Sprite Variables

-- sprite.getvariable(spriteName, variableName) - nil
-- sprite.setvariable(spriteName, variableName, value) - nil
-- sprite.incrementvariable(spriteName, variableName, by) - nil
-- sprite.decrementvariable(spriteName, variableName, by) - nil

-- DOCS - PSIZ(s)

-- psiz.create(x, y, width, height) - PSIZ

-- DOCS - Sprites

-- sprite.create(spriteName, picoSpriteId, PSIZ, collide) - string
-- sprite.updatepsiz(spriteName, PSIZ) - nil
-- sprite.changepsiz(spriteName, PSIZ) - nil
-- sprite.get(spriteName) - Sprite
-- sprite.render(spriteName) - nil
-- sprite.renderall() - nil
-- sprite.updateall() - nil
-- sprite.registereventhandler(spriteName, function(type, me, hitobject)) - nil

-- DOCS - Animations

-- NOTE: this only supports frames made with a sprite number

-- animation.create(animationId, arrayOfFrames) - string
-- sprite.playanimation(spriteName, animationId) - nil

-- DOCS - Printing

-- game.printw(string) - number
-- game.printc(string, x, y) - nil

-- DOCS - Collision (automatically done by game.updateallsprites())

-- game.collidecheck(object1, object2) - bool

-- DOCS - Frames

-- frame.create(spriteId, framesShown) - frame
-- frame.createwithpsiz(spsiz, framesShown) - frame

-- DOCS - Particle

-- particle.create(arrayOfFrames, PSIZ, framesPerParticleFrame) - particle
-- particle.renderall() - nil
-- particle.updateall() - nil

-- Code

game = {
    id = "unknown",
    sprites = {},
    variables = {},
}

enum = {
    eventtype = {
        collision = 0
    }
}

function game.register(id)
    game.id = id
end

function game.update()
    sprite.updateall()
    particle.updateall()
end

function game.render()
    particle.renderall()
    sprite.renderall()
end

-- variable get/set/increment/decrement

variables = {}

function variables.get(tableid)
    return variables[tableid]
end

function variables.set(tableid, value)
    variables[tableid] = value
end

function variables.increment(tableid, value)
    variables[tableid] += value
end

function variables.decrement(tableid, value)
    variables[tableid] -= value
end

-- spritevariable get/set/increment/decrement

sprite = {}

function sprite.getvariable(tableid, variableid)
    return game.sprites[tableid].variables[variableid]
end

function sprite.setvariable(tableid, variableid, value)
    game.sprites[tableid].variables[variableid] = value
end

function sprite.incrementvariable(tableid, variableid, value)
    game.sprites[tableid].variables[variableid] += value
end

function sprite.decrementvariable(tableid, variableid, value)
    game.sprites[tableid].variables[variableid] -= value
end

-- psiz

psiz = {}

function psiz.create(x,y,w,h)
    local psiz = {
        x = (x or 0),
        y = (y or 0),
        w = (w or 8),
        h = (h or 8)
    }
    return psiz
end

-- sprites

animations = {}

function sprite.create(tableid, spriteid, psiz, collide)
    local sprite = {
        id = tableid,
        sid = spriteid,
        x = psiz.x,
        y = psiz.y,
        w = psiz.w,
        h = psiz.h,
        collide = (collide or false),
        eventhandlers = {},
        variables = {},
        animsid = spriteid,
        f = {},
        cf = 1,
        upd = 0,
        tpf = 5,
        playinganim = false,
        update = function()
            local spr = game.sprites[tableid]
            if (spr ~= nil) then
                if (spr.playinganim) then
                    local tpf = spr.f[spr.cf].t
                    if (spr.upd < tpf) then
                        spr.upd += 1
                    else
                        spr.cf += 1
                        spr.upd = 0
                    end
                    if (spr.cf > #spr.f) then
                        spr.playinganim = false
                        spr.animsid = spr.sid
                    else
                        spr.animsid = spr.f[spr.cf].sid
                    end
                end
            end
            game.sprites[tableid] = spr
        end,
        destroy = function()
            game.sprites[tableid] = nil
        end
    }
    game.sprites[tableid] = sprite
    return tableid
end

function sprite.updatepsiz(tableid, psiz)
    local sprite = game.sprites[tableid]
    sprite.x = psiz.x
    sprite.y = psiz.y
    sprite.w = psiz.w
    sprite.h = psiz.h
    game.sprites[tableid] = sprite
    return tableid
end

function sprite.changepsiz(tableid, psiz)
    local sprite = game.sprites[tableid]
    sprite.x += psiz.x
    sprite.y += psiz.y
    sprite.w += psiz.w
    sprite.h += psiz.h
    game.sprites[tableid] = sprite
    return tableid
end

function sprite.get(tableid)
    return game.sprites[tableid]
end

function sprite.render(tableid)
    local sprite = game.sprites[tableid]
    if (not sprite.playinganim) then
        spr(sprite.sid,sprite.x,sprite.y)
    else
        spr(sprite.animsid,sprite.x,sprite.y)
    end
end

function sprite.renderall()
    for k,v in pairs(game.sprites) do
        if (v == nil) then goto skip2 end
        sprite.render(k)
        ::skip2::
    end
end

function sprite.updateall()
    for k,v in pairs(game.sprites) do
        if (v == nil) then goto skip end
        v.update()
        if (v.collide == true) then
            for k2,v2 in pairs(game.sprites) do
                if (k ~= k2 and v2.collide) then
                    if (game.collidecheck(v,v2)) then
                        for v3 in all(v.eventhandlers) do
                            v3(enum.eventtype.collision, v, v2)
                        end
                        goto skip
                    end
                end
            end
        end
        ::skip::
    end
end

function sprite.registereventhandler(tableid,handler)
    add(game.sprites[tableid].eventhandlers,handler)
    return tableid
end

-- animation + sprite extension

animation = {}

function animation.create(animationid, frames)
    local anim = {
        f = frames
    }
    animations[animationid] = anim
    return animationid
end

function sprite.playanimation(tableid, animationid)
    local anim = animations[animationid]
    local spr = game.sprites[tableid]
    spr.f = anim.f
    spr.cf = 1
    spr.upd = 0
    spr.playinganim = true
end

-- printing

function game.printw(s)
    if #s == 0 then 
      return 0
    end

    w = 0
    for i = 1, #s do
        if sub(s,i,i) >= "\x80" then
            w += 7
        else 
            w += 3
        end
    end

    return w + #s - 1
end

function game.printc(s, x, y)
    print(s, x - game.printw(s)/2, y)
end

-- collision

function game.collidecheck(obj1,obj2)
	local hit = false
	if max(obj1.x,obj1.x+obj1.w) >= min(obj2.x, obj2.x+obj2.w) and
				min(obj1.x,obj1.x+obj1.w) <= max(obj2.x, obj2.x+obj2.w) then
		if max(obj1.y,obj1.y+obj1.h) >= min(obj2.y, obj2.y+obj2.h) and
					min(obj1.y,obj1.y+obj1.h) <= max(obj2.y, obj2.y+obj2.h) then
			hit=true
		end
	end
	return hit
end

-- frame

frame = {}

function frame.createwithpsiz(spsiz, tpf)
    local frm = {
        psiz = spsiz,
        sid = nil,
        t = tpf
    }
    return frm
end

function frame.create(spriteid, tpf)
    local frm = {
        psiz = nil,
        sid = spriteid,
        t = tpf
    }
    return frm
end

-- particles

particles = {}

particle = {}

function particle.create(frames, psiz)
    local id = #particles+1
    local prticle = {
        x = psiz.x,
        y = psiz.y,
        f = frames,
        cf = 1,
        upd = 0,
        update = function()
            if particles[id] then
                prtcle = particles[id]
                frm = prtcle.f[prtcle.cf]
                up = prtcle.upd
                prtcle.upd += 1
                if (prtcle.upd > frm.t) then
                    prtcle.cf += 1
                    prtcle.upd = 0
                end
                if (prtcle.cf > #frames) then
                    prtcle.destroy()
                else
                    particles[id] = prtcle
                end
            end
        end,
        render = function()
            if particles[id] then
                prtcle = particles[id] 
                frm = prtcle.f[prtcle.cf]
                if (frm ~= nil and frm.sid ~= nil) then
                    spr(frm.sid,prtcle.x,prtcle.y)
                elseif (frm ~= nil) then
                    sspr(frm.psiz.x,frm.psiz.y,frm.psiz.w,frm.psiz.h,prtcle.x,prtcle.y)
                end
            end
        end,
        destroy = function()
            deli(particles,id)
        end
    }
    particles[id] = prticle
    return id
end

function particle.renderall()
    for k,v in pairs(particles) do
        v.render()
    end
end

function particle.updateall()
    for k,v in pairs(particles) do
        v.update()
    end
end