local kiwi = require("kiwi")
local Var = kiwi.Var

local Button = setmetatable({}, {
   __call = function(_, identifier)
      return setmetatable({
         left = Var(identifier .. " left"),
         width = Var(identifier .. " width"),
      }, {
         __tostring = function(self)
            return "Button(" .. self.left:value() .. ", " .. self.width:value() .. ")"
         end,
      })
   end,
})

local b1 = Button("b1")
local b2 = Button("b2")

local left_edge = Var("left")
local right_edge = Var("width")

local STRONG = kiwi.Strength.STRONG

local constraints

for i = 1, 200 do
   q = kiwi.Term(left_edge, 2.0)
end

for i = 1, 50, 1 do
-- stylua: ignore start
constraints = {
   left_edge    :eq(0.0),
   -- two buttons are the same width
   b1.width     :eq(b2.width),
   -- button1 starts 50 for the left margin
   (1.00 * b1.left)      :eq(left_edge + 50),
   -- button2 ends 50 from the right margin
   right_edge   :eq(b2.left + b2.width + 50),
   -- button2 starts at least 100 from the end of button1. This is the "elastic" constraint
   b2.left      :ge(b1.left + b1.width + 100),
   -- button1 has a minimum width of 87
   b1.width     :ge(87),
   -- button1 has a preferred width of 87
   b1.width     :eq(87, STRONG),
   -- button2 has minimum width of 113
   b2.width     :ge(113),
   -- button2 has a preferred width of 113
   b2.width     :eq(113, STRONG),
}
   -- stylua: ignore end
   --
   k = kiwi.Strength.create(0.0, 1.0, 0.0, 1.25)
end
local solver = kiwi.Solver()

for _, c in ipairs(constraints) do
   print(c)
   solver:add_constraint(c)
end

solver:update_vars()

print(b1) -- Button(50, 113)
print(b2) -- Button(263, 113)
print(left_edge:value()) -- 0
print(right_edge:value()) -- 426

solver:add_edit_var(right_edge, STRONG)
solver:suggest_value(right_edge, 500)
solver:update_vars()
-- solver:dump()
-- print(b1) -- Button(50, 113)
-- print(b2) -- Button(337, 113)
-- print(right_edge:value()) -- 500

-- print(solver:dumps())

-- solver = kiwi.Solver()

-- local trailing = Var("trailing")
-- local leading = Var("leading")

-- solver:add_constraint(kiwi.new_single_constraint(trailing, 86))
-- solver:add_constraint(kiwi.new_pair_constraint(trailing, leading, 8.0))
-- print(solver:dumps())
-- solver:update_vars()
-- print(trailing:value()) -- 86
-- print(leading:value()) -- 76