From b4e860322d6dd4ab8ac2def72a27e8891415edbe Mon Sep 17 00:00:00 2001
From: Eric Wong <eric@wsdjeg.net>
Date: Sat, 13 Jul 2024 18:52:07 +0800
Subject: [PATCH] feat(hsv): add hsv format

---
 bundle/cpicker.nvim/lua/cpicker.lua           | 227 ++++--------------
 .../cpicker.nvim/lua/cpicker/formats/hsl.lua  | 109 +++++++++
 .../cpicker.nvim/lua/cpicker/formats/hsv.lua  | 110 +++++++++
 .../cpicker.nvim/lua/cpicker/formats/rgb.lua  |  89 +++++++
 bundle/cpicker.nvim/lua/cpicker/util.lua      |  22 ++
 .../cpicker.nvim/syntax/spacevim_cpicker.vim  |   2 +-
 lua/spacevim/api/color.lua                    |  93 +++++++
 7 files changed, 465 insertions(+), 187 deletions(-)
 create mode 100644 bundle/cpicker.nvim/lua/cpicker/formats/hsl.lua
 create mode 100644 bundle/cpicker.nvim/lua/cpicker/formats/hsv.lua
 create mode 100644 bundle/cpicker.nvim/lua/cpicker/formats/rgb.lua
 create mode 100644 bundle/cpicker.nvim/lua/cpicker/util.lua

diff --git a/bundle/cpicker.nvim/lua/cpicker.lua b/bundle/cpicker.nvim/lua/cpicker.lua
index 372b1f6d5..413f54bf3 100644
--- a/bundle/cpicker.nvim/lua/cpicker.lua
+++ b/bundle/cpicker.nvim/lua/cpicker.lua
@@ -10,197 +10,37 @@ local M = {}
 
 local winid
 local bufnr
+local color_hi = '#000000'
 
 local hi = require('spacevim.api.vim.highlight')
-local color = require('spacevim.api.color')
 local notify = require('spacevim.api.notify')
+local log = require('spacevim.logger').derive('cpicker')
+local util = require('cpicker.util')
 
-local red = 0 -- [0, 255]
-local green = 0 -- [0, 255]
-local blue = 0 -- [0, 255]
-local hue = 0 -- [0, 360]
-local saturation = 0 -- [0, 100%]
-local lightness = 0 -- [0, 100%]
 local enabled_formats = {}
 local increase_keys = {}
 local reduce_keys = {}
 
-local function decimalToHex(decimal)
-  local hex = ''
-  local hexChars = '0123456789ABCDEF'
-  while decimal > 0 do
-    local mod = decimal % 16
-    hex = string.sub(hexChars, mod + 1, mod + 1) .. hex
-    decimal = math.floor(decimal / 16)
-  end
-  if hex == '' then
-    return '00'
-  elseif #hex == 1 then
-    return '0' .. hex
-  else
-    return hex
-  end
-end
-
-local function generate_bar(n, char, m)
-  return string.rep(char, math.floor(24 * n / (m or 255)))
-end
-local function increase_rgb_red()
-  if red < 255 then
-    red = red + 1
-    hue, saturation, lightness = color.rgb2hsl(red, green, blue)
-  end
-end
-local function reduce_rgb_red()
-  if red > 0 then
-    red = red - 1
-    hue, saturation, lightness = color.rgb2hsl(red, green, blue)
-  end
-end
-local function increase_rgb_green()
-  if green < 255 then
-    green = green + 1
-    hue, saturation, lightness = color.rgb2hsl(red, green, blue)
-  end
-end
-local function reduce_rgb_green()
-  if green > 0 then
-    green = green - 1
-    hue, saturation, lightness = color.rgb2hsl(red, green, blue)
-  end
-end
-
-local function increase_rgb_blue()
-  if blue < 255 then
-    blue = blue + 1
-    hue, saturation, lightness = color.rgb2hsl(red, green, blue)
-  end
-end
-
-local function reduce_rgb_blue()
-  if blue > 0 then
-    blue = blue - 1
-    hue, saturation, lightness = color.rgb2hsl(red, green, blue)
-  end
-end
-
-local function increase_hsl_h()
-  if hue < 360 then
-    hue = hue + 1
-    red, green, blue = color.hsl2rgb(hue, saturation, lightness)
-  end
-end
-local function reduce_hsl_h()
-  if hue >= 1 then
-    hue = hue - 1
-  elseif hue > 0 then
-    hue = 0
-  end
-  red, green, blue = color.hsl2rgb(hue, saturation, lightness)
-end
-local function increase_hsl_s()
-  if saturation <= 0.99 then
-    saturation = saturation + 0.01
-  elseif saturation < 1 then
-    saturation = 1
-  end
-  red, green, blue = color.hsl2rgb(hue, saturation, lightness)
-end
-local function reduce_hsl_s()
-  if saturation >= 0.01 then
-    saturation = saturation - 0.01
-  elseif saturation > 0 and saturation < 0.01 then
-    saturation = 0
-  end
-  red, green, blue = color.hsl2rgb(hue, saturation, lightness)
-end
-local function increase_hsl_l()
-  if lightness <= 0.99 then
-    lightness = lightness + 0.01
-  elseif lightness < 1 then
-    lightness = 1
-  end
-  red, green, blue = color.hsl2rgb(hue, saturation, lightness)
-end
-local function reduce_hsl_l()
-  if lightness >= 0.01 then
-    lightness = lightness - 0.01
-  elseif lightness > 0 and lightness < 0.01 then
-    lightness = 0
-  end
-  red, green, blue = color.hsl2rgb(hue, saturation, lightness)
-end
-
 local function update_buf_text()
   local rst = {}
-  local r_bar = generate_bar(red, '+')
-  local g_bar = generate_bar(green, '+')
-  local b_bar = generate_bar(blue, '+')
-  local h_bar = generate_bar(hue, '+', 360)
-  local s_bar = generate_bar(saturation, '+', 1)
-  local l_bar = generate_bar(lightness, '+', 1)
-  if enabled_formats.all or enabled_formats.rgb then
-    table.insert(rst, 'R:    ' .. string.format('%4s', red) .. ' ' .. r_bar)
-    increase_keys[#rst] = increase_rgb_red
-    reduce_keys[#rst] = reduce_rgb_red
-    table.insert(rst, 'G:    ' .. string.format('%4s', green) .. ' ' .. g_bar)
-    increase_keys[#rst] = increase_rgb_green
-    reduce_keys[#rst] = reduce_rgb_green
-    table.insert(rst, 'B:    ' .. string.format('%4s', blue) .. ' ' .. b_bar)
-    increase_keys[#rst] = increase_rgb_blue
-    reduce_keys[#rst] = reduce_rgb_blue
-  end
-  if enabled_formats.all or enabled_formats.hsl then
-    table.insert(rst, 'H:    ' .. string.format('%4s', math.floor(hue + 0.5)) .. ' ' .. h_bar)
-    increase_keys[#rst] = increase_hsl_h
-    reduce_keys[#rst] = reduce_hsl_h
-    table.insert(
-      rst,
-      'S:    ' .. string.format('%3s', math.floor(saturation * 100 + 0.5)) .. '% ' .. s_bar
-    )
-    increase_keys[#rst] = increase_hsl_s
-    reduce_keys[#rst] = reduce_hsl_s
-    table.insert(
-      rst,
-      'L:    ' .. string.format('%3s', math.floor(lightness * 100 + 0.5)) .. '% ' .. l_bar
-    )
-    increase_keys[#rst] = increase_hsl_l
-    reduce_keys[#rst] = reduce_hsl_l
+  for _, format in ipairs(enabled_formats) do
+    local ok, f = pcall(require, 'cpicker.formats.' .. format)
+    if ok then
+      local funcs = f.increase_reduce_functions()
+      for i, text in ipairs(f.buf_text()) do
+        table.insert(rst, text)
+        increase_keys[#rst] = funcs[i][1]
+        reduce_keys[#rst] = funcs[i][2]
+      end
+    end
   end
   table.insert(rst, '')
-  local r = decimalToHex(red)
-  local g = decimalToHex(green)
-  local b = decimalToHex(blue)
-  if not vim.g.cpicker_default_format or vim.g.cpicker_default_format == 'hex' then
-    table.insert(rst, '   =========' .. '  #' .. r .. g .. b)
-  elseif vim.g.cpicker_default_format == 'rgb' then
-    table.insert(rst, '   =========' .. string.format('  rgb(%s, %s, %s)', red, green, blue))
-  elseif vim.g.cpicker_default_format == 'hsl' then
-    table.insert(
-      rst,
-      '   ========='
-        .. string.format(
-          '  hsl(%s, %s%%, %s%%)',
-          math.floor(hue + 0.5),
-          math.floor(saturation * 100 + 0.5),
-          math.floor(lightness * 100 + 0.5)
-        )
-    )
-  elseif vim.g.cpicker_default_format == 'all' then
-    table.insert(rst, '   =========' .. '  #' .. r .. g .. b)
-    table.insert(rst, '   =========' .. string.format('  rgb(%s, %s, %s)', red, green, blue))
-    table.insert(
-      rst,
-      '   ========='
-        .. string.format(
-          '  hsl(%s, %s%%, %s%%)',
-          math.floor(hue + 0.5),
-          math.floor(saturation * 100 + 0.5),
-          math.floor(lightness * 100 + 0.5)
-        )
-    )
+  for _, format in ipairs(enabled_formats) do
+    local ok, f = pcall(require, 'cpicker.formats.' .. format)
+    if ok then
+      table.insert(rst, f.color_code())
+    end
   end
-  local color_hi = '#' .. r .. g .. b
   local normal_bg = hi.group2dict('Normal').guibg
   hi.hi({
     name = 'SpaceVimPickerCode',
@@ -225,13 +65,16 @@ local function update_buf_text()
   vim.api.nvim_set_option_value('modifiable', false, {
     buf = bufnr,
   })
+  vim.api.nvim_win_set_config(winid, {
+    height = #rst + 1
+  })
 end
 
 -- https://zenn.dev/kawarimidoll/articles/a8ac50a17477bd
 
 local function copy_color()
-  local from, to  = vim
-    .regex([[#[0123456789ABCDEF]\+\|rgb(\d\+,\s\d\+,\s\d\+)\|hsl(\d\+,\s\d\+%,\s\d\+%)]])
+  local from, to = vim
+    .regex([[#[0123456789ABCDEF]\+\|rgb(\d\+,\s\d\+,\s\d\+)\|hsl(\d\+,\s\d\+%,\s\d\+%)\|hsv(\d\+,\s\d\+%,\s\d\+%)]])
     :match_str(vim.fn.getline('.'))
   if from then
     vim.fn.setreg('+', string.sub(vim.fn.getline('.'), from, to + 1))
@@ -241,23 +84,35 @@ end
 
 local function increase()
   if increase_keys[vim.fn.line('.')] then
-    increase_keys[vim.fn.line('.')]()
+    local t, code = increase_keys[vim.fn.line('.')]()
+    color_hi = util.get_hex_code(t, code)
+    for _, format in ipairs(enabled_formats) do
+      local ok, f = pcall(require, 'cpicker.formats.' .. format)
+      if ok then
+        f.on_change(t, code)
+      end
+    end
   end
   update_buf_text()
 end
 
 local function reduce()
   if reduce_keys[vim.fn.line('.')] then
-    reduce_keys[vim.fn.line('.')]()
+    local t, code = reduce_keys[vim.fn.line('.')]()
+    color_hi = util.get_hex_code(t, code)
+    for _, format in ipairs(enabled_formats) do
+      local ok, f = pcall(require, 'cpicker.formats.' .. format)
+      if ok then
+        f.on_change(t, code)
+      end
+    end
   end
   update_buf_text()
 end
 
 M.picker = function(formats)
-  enabled_formats = {}
-  for _, v in ipairs(formats) do
-    enabled_formats[v] = true
-  end
+  enabled_formats = formats
+  log.info(vim.inspect(enabled_formats))
   if not bufnr or not vim.api.nvim_win_is_valid(bufnr) then
     bufnr = vim.api.nvim_create_buf(false, false)
     vim.api.nvim_set_option_value('buftype', 'nofile', {
diff --git a/bundle/cpicker.nvim/lua/cpicker/formats/hsl.lua b/bundle/cpicker.nvim/lua/cpicker/formats/hsl.lua
new file mode 100644
index 000000000..af38f6ce4
--- /dev/null
+++ b/bundle/cpicker.nvim/lua/cpicker/formats/hsl.lua
@@ -0,0 +1,109 @@
+--=============================================================================
+-- hsl.lua
+-- Copyright (c) 2019-2024 Wang Shidong & Contributors
+-- Author: Wang Shidong < wsdjeg@outlook.com >
+-- URL: https://spacevim.org
+-- License: GPLv3
+--=============================================================================
+local M = {}
+
+local color = require('spacevim.api.color')
+local util = require('cpicker.util')
+
+local hue = 0 -- [0, 360]
+local saturation = 0 -- [0, 100%]
+local lightness = 0 -- [0, 100%]
+
+local function on_change_argv()
+  return 'hsl', { hue, saturation, lightness }
+end
+
+function M.buf_text()
+  local rst = {}
+  local h_bar = util.generate_bar(hue, '+', 360)
+  local s_bar = util.generate_bar(saturation, '+', 1)
+  local l_bar = util.generate_bar(lightness, '+', 1)
+  table.insert(rst, 'HSL:  H:    ' .. string.format('%4s', math.floor(hue + 0.5)) .. ' ' .. h_bar)
+  table.insert(
+    rst,
+    '      S:    ' .. string.format('%3s', math.floor(saturation * 100 + 0.5)) .. '% ' .. s_bar
+  )
+  table.insert(
+    rst,
+    '      L:    ' .. string.format('%3s', math.floor(lightness * 100 + 0.5)) .. '% ' .. l_bar
+  )
+  return rst
+end
+
+function M.color_code()
+  return
+    '   =========' .. string.format(
+    '  hsl(%s, %s%%, %s%%)',
+    math.floor(hue + 0.5),
+    math.floor(saturation * 100 + 0.5),
+    math.floor(lightness * 100 + 0.5)
+  )
+end
+
+local function increase_hsl_h()
+  if hue < 360 then
+    hue = hue + 1
+  end
+  return on_change_argv()
+end
+local function reduce_hsl_h()
+  if hue >= 1 then
+    hue = hue - 1
+  elseif hue > 0 then
+    hue = 0
+  end
+  return on_change_argv()
+end
+local function increase_hsl_s()
+  if saturation <= 0.99 then
+    saturation = saturation + 0.01
+  elseif saturation < 1 then
+    saturation = 1
+  end
+  return on_change_argv()
+end
+local function reduce_hsl_s()
+  if saturation >= 0.01 then
+    saturation = saturation - 0.01
+  elseif saturation > 0 and saturation < 0.01 then
+    saturation = 0
+  end
+  return on_change_argv()
+end
+local function increase_hsl_l()
+  if lightness <= 0.99 then
+    lightness = lightness + 0.01
+  elseif lightness < 1 then
+    lightness = 1
+  end
+  return on_change_argv()
+end
+local function reduce_hsl_l()
+  if lightness >= 0.01 then
+    lightness = lightness - 0.01
+  elseif lightness > 0 and lightness < 0.01 then
+    lightness = 0
+  end
+  return on_change_argv()
+end
+function M.increase_reduce_functions()
+  return {
+    { increase_hsl_h, reduce_hsl_h },
+    { increase_hsl_s, reduce_hsl_s },
+    { increase_hsl_l, reduce_hsl_l },
+  }
+end
+
+function M.on_change(f, code)
+  if f == 'hsl' then
+    return
+  end
+  hue, saturation, lightness = color[f .. '2hsl'](unpack(code))
+end
+
+return M
diff --git a/bundle/cpicker.nvim/lua/cpicker/formats/hsv.lua b/bundle/cpicker.nvim/lua/cpicker/formats/hsv.lua
new file mode 100644
index 000000000..ce0786eaa
--- /dev/null
+++ b/bundle/cpicker.nvim/lua/cpicker/formats/hsv.lua
@@ -0,0 +1,110 @@
+--=============================================================================
+-- hsv.lua --- 
+-- Copyright (c) 2019-2024 Wang Shidong & Contributors
+-- Author: Wang Shidong < wsdjeg@outlook.com >
+-- URL: https://spacevim.org
+-- License: GPLv3
+--=============================================================================
+local M = {}
+
+local color = require('spacevim.api.color')
+local util = require('cpicker.util')
+
+local hue = 0
+local saturation = 0
+local value = 0
+
+local function on_change_argv()
+  return 'hsv', {hue, saturation, value}
+end
+
+function M.buf_text()
+  
+  local rst = {}
+  local h_bar = util.generate_bar(hue, '+', 360)
+  local s_bar = util.generate_bar(saturation, '+', 1)
+  local l_bar = util.generate_bar(value, '+', 1)
+  table.insert(rst, 'HSV:  H:    ' .. string.format('%4s', math.floor(hue + 0.5)) .. ' ' .. h_bar)
+  table.insert(
+    rst,
+    '      S:    ' .. string.format('%3s', math.floor(saturation * 100 + 0.5)) .. '% ' .. s_bar
+  )
+  table.insert(
+    rst,
+    '      V:    ' .. string.format('%3s', math.floor(value * 100 + 0.5)) .. '% ' .. l_bar
+  )
+  return rst
+end
+
+function M.color_code()
+  return
+    '   =========' .. string.format(
+    '  hsv(%s, %s%%, %s%%)',
+    math.floor(hue + 0.5),
+    math.floor(saturation * 100 + 0.5),
+    math.floor(value * 100 + 0.5)
+  )
+  
+end
+local function increase_hsl_h()
+  if hue < 360 then
+    hue = hue + 1
+  end
+  return on_change_argv()
+end
+local function reduce_hsl_h()
+  if hue >= 1 then
+    hue = hue - 1
+  elseif hue > 0 then
+    hue = 0
+  end
+  return on_change_argv()
+end
+local function increase_hsl_s()
+  if saturation <= 0.99 then
+    saturation = saturation + 0.01
+  elseif saturation < 1 then
+    saturation = 1
+  end
+  return on_change_argv()
+end
+local function reduce_hsl_s()
+  if saturation >= 0.01 then
+    saturation = saturation - 0.01
+  elseif saturation > 0 and saturation < 0.01 then
+    saturation = 0
+  end
+  return on_change_argv()
+end
+local function increase_hsl_v()
+  if value <= 0.99 then
+    value = value + 0.01
+  elseif value < 1 then
+    value = 1
+  end
+  return on_change_argv()
+end
+local function reduce_hsl_v()
+  if value >= 0.01 then
+    value = value - 0.01
+  elseif value > 0 and value < 0.01 then
+    value = 0
+  end
+  return on_change_argv()
+end
+function M.increase_reduce_functions()
+  return {
+    { increase_hsl_h, reduce_hsl_h },
+    { increase_hsl_s, reduce_hsl_s },
+    { increase_hsl_v, reduce_hsl_v },
+  }
+end
+
+function M.on_change(f, code)
+  if f == 'hsv' then
+    return
+  end
+  hue, saturation, value = color[f .. '2hsv'](unpack(code))
+end
+
+return M
diff --git a/bundle/cpicker.nvim/lua/cpicker/formats/rgb.lua b/bundle/cpicker.nvim/lua/cpicker/formats/rgb.lua
new file mode 100644
index 000000000..7856951fe
--- /dev/null
+++ b/bundle/cpicker.nvim/lua/cpicker/formats/rgb.lua
@@ -0,0 +1,89 @@
+--=============================================================================
+-- rgb.lua ---
+-- Copyright (c) 2019-2024 Wang Shidong & Contributors
+-- Author: Wang Shidong < wsdjeg@outlook.com >
+-- URL: https://spacevim.org
+-- License: GPLv3
+--=============================================================================
+local M = {}
+
+local color = require('spacevim.api.color')
+local util = require('cpicker.util')
+
+local red = 0 -- [0, 255]
+local green = 0 -- [0, 255]
+local blue = 0 -- [0, 255]
+
+local function on_change_argv()
+  return 'rgb', { red, green, blue }
+end
+
+function M.buf_text()
+  local rst = {}
+  local r_bar = util.generate_bar(red, '+')
+  local g_bar = util.generate_bar(green, '+')
+  local b_bar = util.generate_bar(blue, '+')
+  table.insert(rst, 'RGB:  R:    ' .. string.format('%4s', red) .. ' ' .. r_bar)
+  table.insert(rst, '      G:    ' .. string.format('%4s', green) .. ' ' .. g_bar)
+  table.insert(rst, '      B:    ' .. string.format('%4s', blue) .. ' ' .. b_bar)
+  return rst
+end
+
+function M.color_code()
+  return '   =========' .. '  ' .. color.rgb2hex(red, green, blue)
+end
+
+local function increase_rgb_red()
+  if red < 255 then
+    red = red + 1
+  end
+  return on_change_argv()
+end
+local function reduce_rgb_red()
+  if red > 0 then
+    red = red - 1
+  end
+  return on_change_argv()
+end
+local function increase_rgb_green()
+  if green < 255 then
+    green = green + 1
+  end
+  return on_change_argv()
+end
+local function reduce_rgb_green()
+  if green > 0 then
+    green = green - 1
+  end
+  return on_change_argv()
+end
+
+local function increase_rgb_blue()
+  if blue < 255 then
+    blue = blue + 1
+  end
+  return on_change_argv()
+end
+
+local function reduce_rgb_blue()
+  if blue > 0 then
+    blue = blue - 1
+  end
+  return on_change_argv()
+end
+function M.increase_reduce_functions()
+  return {
+    { increase_rgb_red, reduce_rgb_red },
+    { increase_rgb_green, reduce_rgb_green },
+    { increase_rgb_blue, reduce_rgb_blue },
+  }
+end
+
+function M.on_change(f, code)
+  if f == 'rgb' then
+    return
+  end
+  red, green, blue = color[f .. '2rgb'](unpack(code))
+end
+
+return M
diff --git a/bundle/cpicker.nvim/lua/cpicker/util.lua b/bundle/cpicker.nvim/lua/cpicker/util.lua
new file mode 100644
index 000000000..1a03fb06e
--- /dev/null
+++ b/bundle/cpicker.nvim/lua/cpicker/util.lua
@@ -0,0 +1,22 @@
+--=============================================================================
+-- util.lua
+-- Copyright (c) 2019-2024 Wang Shidong & Contributors
+-- Author: Wang Shidong < wsdjeg@outlook.com >
+-- URL: https://spacevim.org
+-- License: GPLv3
+--=============================================================================
+
+
+local M = {}
+
+local color = require('spacevim.api.color')
+
+function M.generate_bar(n, char, m)
+  return string.rep(char, math.floor(24 * n / (m or 255)))
+end
+
+function M.get_hex_code(t, code)
+  return color[t .. '2hex'](unpack(code))
+end
+
+return M
diff --git a/bundle/cpicker.nvim/syntax/spacevim_cpicker.vim b/bundle/cpicker.nvim/syntax/spacevim_cpicker.vim
index 19f0e37bb..c172ca18a 100644
--- a/bundle/cpicker.nvim/syntax/spacevim_cpicker.vim
+++ b/bundle/cpicker.nvim/syntax/spacevim_cpicker.vim
@@ -5,7 +5,7 @@ let b:current_syntax = 'spacevim_cpicker'
 syntax case ignore
 
 syn match ProcessBar /[?=+]\+/
-syn match SpaceVimPickerCode /#[0123456789ABCDEF]\+\|rgb(\d\+,\s\d\+,\s\d\+)\|hsl(\d\+,\s\d\+%,\s\d\+%)/
+syn match SpaceVimPickerCode /#[0123456789ABCDEF]\+\|rgb(\d\+,\s\d\+,\s\d\+)\|hsl(\d\+,\s\d\+%,\s\d\+%)\|hsv(\d\+,\s\d\+%,\s\d\+%)/
 syn match SpaceVimPickerBackground /=\+/
 
 highlight ProcessBar ctermfg=Gray ctermbg=Gray guifg=Gray guibg=Gray
diff --git a/lua/spacevim/api/color.lua b/lua/spacevim/api/color.lua
index 2e9ad7552..dbae1d7b1 100644
--- a/lua/spacevim/api/color.lua
+++ b/lua/spacevim/api/color.lua
@@ -81,4 +81,97 @@ color.hsl2rgb = function(h, s, l)
   return math.floor(r * 255), math.floor(g * 255), math.floor(b * 255)
 end
 
+-- https://www.rapidtables.com/convert/color/rgb-to-hsv.html
+
+color.rgb2hsv = function(r, g, b)
+  r = r / 255
+  g = g / 255
+  b = b / 255
+
+  local cmax = math.max(r, g, b)
+  local cmin = math.min(r, g, b)
+  local d = cmax - cmin
+
+  local h, s, v
+
+  if d == 0 then
+    h = 0
+  elseif cmax == r then
+    h = 60 * (((g - b) / d) % 6)
+  elseif cmax == g then
+    h = 60 * (((b - r) / d) + 2)
+  elseif cmax == b then
+    h = 60 * (((r - g) / d) + 4)
+  end
+
+  if cmax == 0 then
+    s = 0
+  else
+    s = d / cmax
+  end
+
+  v = cmax
+
+  return math.floor(h), s, v
+end
+
+-- https://www.rapidtables.com/convert/color/hsv-to-rgb.html
+color.hsv2rgb = function(h, s, v)
+  local c = v * s
+  local x = c * (1 - math.abs((h / 60) % 2 - 1))
+  local m = v - c
+  local r, g, b
+
+  if h >= 0 and h < 60 then
+    r, g, b = c, x, 0
+  elseif h >= 60 and h < 120 then
+    r, g, b = x, c, 0
+  elseif h >= 120 and h < 180 then
+    r, g, b = 0, c, x
+  elseif h >= 180 and h < 240 then
+    r, g, b = 0, x, c
+  elseif h >= 240 and h < 300 then
+    r, g, b = x, 0, c
+  elseif h >= 300 and h < 360 then
+    r, g, b = c, 0, x
+  end
+  r, g, b = (r + m), (g + m), (b + m)
+  return math.floor(r * 255), math.floor(g * 255), math.floor(b * 255)
+end
+color.hsv2hsl = function(h, s, v)
+  return color.rgb2hsl(color.hsv2rgb(h, s, v))
+end
+color.hsl2hsv = function(h, s, l)
+  return color.rgb2hsv(color.hsl2rgb(h, s, l))
+end
+
+local function decimalToHex(decimal)
+  local hex = ''
+  local hexChars = '0123456789ABCDEF'
+  while decimal > 0 do
+    local mod = decimal % 16
+    hex = string.sub(hexChars, mod + 1, mod + 1) .. hex
+    decimal = math.floor(decimal / 16)
+  end
+  if hex == '' then
+    return '00'
+  elseif #hex == 1 then
+    return '0' .. hex
+  else
+    return hex
+  end
+end
+color.rgb2hex = function(r, g, b)
+  r = decimalToHex(r)
+  g = decimalToHex(g)
+  b = decimalToHex(b)
+  return '#' .. r .. g .. b
+end
+color.hsv2hex = function(h, s, v)
+  return color.rgb2hex(color.hsv2rgb(h, s, v))
+end
+color.hsl2hex = function(h, s, l)
+  return color.rgb2hex(color.hsl2rgb(h, s, l))
+end
+
 return color