require 'tablefuncs'
require 'gridpoint'
require 'port'

---@param xcorner GridPoint
---@param size GridPoint
---@return GridPoint
local function nextxcorner( xcorner, size )
    local cornerLookup = {
        GridPoint:new( 0, 0 ),
        GridPoint:new( size.x - 1, 0 ),
        GridPoint:new( size.x - 1, size.y - 1 ),
        GridPoint:new( size.x - 1, size.y - 1 )
    }
    local index = TableFind(cornerLookup, xcorner, function(value) value:equals(xcorner) end)
    if index < #cornerLookup then
        index = index + 1
    else
        index = 0
    end
    return cornerLookup[index]
end

---@class Mechanism
---@field position GridPoint
---@field size GridPoint
---@field xcorner GridPoint
---@field ports Port[]
---@field color table
Mechanism = {
    position = GridPoint:new( 0, 0 ),
    size = GridPoint:new( 1, 1 ),
    xcorner = GridPoint:new( 0, 0 ),
    ports = {},
    color = { 0.5, 0.5, 0.5, 1 }
}

function Mechanism:new( position, size, ports, color )
    local mechanism = {
        position = position or self.position,
        size = size or self.size,
        ports = ports or {},
        color = color or self.color
    }

    setmetatable( mechanism, { __index = self } )

    return mechanism
end

function Mechanism:rotateClockwise()
    self.xcorner = nextxcorner(self.xcorner, self.size)
    for _, port in ipairs(self.ports) do
        port:rotateClockwise()
    end
end

function Mechanism:draw()
    love.graphics.setColor(self.color)
    local x, y = self.position:globalCoords()
    x = x - Config.cellSize / 2
    y = y - Config.cellSize / 2
    local w, h = self.size:globalCoords()
    love.graphics.rectangle("fill", x, y, w, h)
    for _, port in ipairs(self.ports) do
        local offset = GridPoint:new( self.position.x + self.xcorner.x, self.position.y + self.xcorner.y )
        port:draw( offset )
    end
end