local heightmap = require "lib.heightmap"
local lovebird = require "lib.lovebird"
local lume = require "lib.lume"

local map = {}

love.load = function()
  map.size = 150
  map.height = heightmap.create(map.size, map.size, 0, 1)
  map.temperature = heightmap.create(map.size, map.size, 0, 1)
  map.humidity = heightmap.create(map.size, map.size, 0, 1)

  -- weird mixing idea test
  -- why does this average things out?
  -- trying to renormalize it now..
  local temporary_maps = {}
  for i = 1, 3 do
    temporary_maps[i] = heightmap.create(map.size, map.size, 0, 1)
  end
  for x = 0, map.height.w do
    for y = 0, map.height.h do
      map.height[x][y] = (map.height[x][y] + temporary_maps[1][x][y] + temporary_maps[2][x][y] + temporary_maps[3][x][y] ) / 4
    end
  end
  heightmap.normalize(map.height, 0, 1)

  -- if true then return end

  -- lower temperature by half height
  -- NOTE ruins "normalization" but that's fine once we have "real" numbers to work with
  for x = 0, map.temperature.w do
    for y = 0, map.temperature.h do
      map.temperature[x][y] = math.max(0, map.temperature[x][y] - map.height[x][y] / 2)
    end
  end

  -- modify temperature by latitude
  -- TODO would be more efficient to calculate Y in outer loop, since X does not change the distance
  -- NOTE only subtracts temperature, which further "ruins normalization" and makes everything too cold:
  local center_y = map.size / 2
  for x = 0, map.temperature.w do
    for y = 0, map.temperature.h do
      local distance = math.abs(y - center_y)
      map.temperature[x][y] = lume.clamp(map.temperature[x][y] - distance / map.size / 2, 0, 1)
    end
  end

  -- increase humidity by half temperature
  for x = 0, map.humidity.w do
    for y = 0, map.humidity.h do
      map.humidity[x][y] = math.min(1, map.humidity[x][y] + map.temperature[x][y] / 2)
    end
  end

  -- planetizer!
  local radius = (map.size / 2)^2
  for x = 0, map.height.w do
    for y = 0, map.height.h do
      if lume.distance(x, y, map.size / 2, map.size / 2, true) > radius then
        map.height[x][y] = nil
      end
    end
  end
end

love.update = function(dt)
  lovebird.update()
end

love.draw = function()
  local tile_size = 2

  for x = 0, map.height.w do
    for y = 0, map.height.h do
      -- raw heightmap
      -- NOTE will break with planetizer enabled!
      -- local value = map.height[x][y]
      -- love.graphics.setColor(value, value, value, 1)
      -- love.graphics.rectangle("fill", x * tile_size, y * tile_size, tile_size, tile_size)

      -- even weighting between height and temperature
      -- local value = map.height[x][y] / 2 + map.temperature[x][y] / 2
      -- if value < 0.2 then
      --   love.graphics.setColor(0, 0, 1, 1)
      -- elseif value < 0.215 then
      --   love.graphics.setColor(1, 1, 0, 1)
      -- elseif value < 0.34 then
      --   love.graphics.setColor(0, 1, 0, 1)
      -- elseif value < 0.72 then
      --   love.graphics.setColor(0, 0.67, 0, 1)
      -- elseif value < 0.9 then
      --   love.graphics.setColor(0.67, 0.67, 0.67, 1)
      -- else
      --   -- love.graphics.setColor(0, 0, 0, 1) -- temporary nothing
      --   love.graphics.setColor(1, 1, 1, 1)
      -- end
      -- love.graphics.rectangle("fill", x * tile_size, y * tile_size, tile_size, tile_size)

      -- temperature map
      local value = map.temperature[x][y]
      love.graphics.setColor(value, 0, 0, 1)
      love.graphics.rectangle("fill", map.size * tile_size + x * tile_size, y * tile_size, tile_size, tile_size)

      -- humidity map
      local value = map.humidity[x][y]
      love.graphics.setColor(0, 0, value, 1)
      love.graphics.rectangle("fill", x * tile_size, map.size * tile_size + y * tile_size, tile_size, tile_size)

      -- "naive" biomed map
      local value = map.height[x][y]
      if value then
        if value < 0.2 then
          love.graphics.setColor(0, 0, 1, 1)
        elseif value < 0.215 then
          love.graphics.setColor(1, 1, 0, 1)
        elseif value < 0.34 then
          love.graphics.setColor(0, 1, 0, 1)
        elseif value < 0.72 then
          love.graphics.setColor(0, 0.67, 0, 1)
        elseif value < 0.9 then
          love.graphics.setColor(0.67, 0.67, 0.67, 1)
        else
          -- love.graphics.setColor(0, 0, 0, 1) -- temporary nothing
          love.graphics.setColor(1, 1, 1, 1)
        end
        love.graphics.rectangle("fill", map.size * tile_size + x * tile_size, map.size * tile_size + y * tile_size, tile_size, tile_size)
      end
    end
  end
end

love.keypressed = function(key)
  if key == "escape" then
    love.event.quit()
  elseif key == "r" then
    love.load()
  end
end