Feature to add a custom theme (#19)

Closes #21 

Co-authored-by: Olivier Roques <olivier@oroques.dev>

lua/hardline.lua

@@ -8,6 +8,7 @@ local g, o, wo = vim.g, vim.o, vim.wo
 local fmt = string.format
 local common = require('hardline.common')
 local bufferline = require('hardline.bufferline')
+local custom_colors = require('hardline.themes.custom_colors')
 local M = {}
 
 -------------------- OPTIONS -------------------------------
@@ -19,6 +20,19 @@ M.options = {
       separator = '|',
   },
   theme = 'default',
+  custom_theme = {
+    text = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    normal = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    insert = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    replace = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    inactive_comment = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    inactive_cursor = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    inactive_menu = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    visual = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    command = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    alt_text = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+    warning = {gui = "NONE", cterm = "NONE", cterm16 = "NONE"},
+  },
   sections = {
     {class = 'mode', item = require('hardline.parts.mode').get_item},
     {class = 'high', item = require('hardline.parts.git').get_item, hide = 80},
@@ -182,8 +196,12 @@ local function set_theme()
   if type(M.options.theme) ~= 'string' then
     return
   end
-  local theme = fmt('hardline.themes.%s', M.options.theme)
-  M.options.theme = require(theme)
+  if M.options.theme == 'custom' then
+    M.options.theme = custom_colors.set(M.options.custom_theme)
+  else
+    local theme = fmt('hardline.themes.%s', M.options.theme)
+    M.options.theme = require(theme)
+  end
 end
 
 local function set_hlgroups()

lua/hardline/themes/custom_colors.lua

@@ -0,0 +1,122 @@
+-- Custom colorscheme
+
+local M = {}
+
+M.set = function(color_table)
+  local inactive = {
+    guifg = color_table.inactive_comment.gui,
+    guibg = color_table.inactive_cursor.gui,
+    ctermfg = color_table.inactive_comment.cterm,
+    ctermbg = color_table.inactive_cursor.cterm,
+  }
+
+  return {
+    mode = {
+      inactive = inactive,
+      normal = {
+        guifg = color_table.text.gui,
+        guibg = color_table.normal.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.normal.cterm,
+      },
+      insert = {
+        guifg = color_table.text.gui,
+        guibg = color_table.insert.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.insert.cterm,
+      },
+      replace = {
+        guifg = color_table.text.gui,
+        guibg = color_table.replace.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.replace.cterm,
+      },
+      visual = {
+        guifg = color_table.text.gui,
+        guibg = color_table.visual.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.visual.cterm,
+      },
+      command = {
+        guifg = color_table.text.gui,
+        guibg = color_table.command.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.command.cterm,
+      },
+    },
+    low = {
+      active = {
+        guifg = color_table.alt_text.gui,
+        guibg = color_table.inactive_cursor.gui,
+        ctermfg = color_table.alt_text.cterm,
+        ctermbg = color_table.inactive_cursor.cterm,
+      },
+      inactive = inactive,
+    },
+    med = {
+      active = {
+        guifg = color_table.alt_text.gui,
+        guibg = color_table.inactive_cursor.gui,
+        ctermfg = color_table.alt_text.cterm,
+        ctermbg = color_table.inactive_cursor.cterm,
+      },
+      inactive = inactive,
+    },
+    high = {
+      active = {
+        guifg = color_table.alt_text.gui,
+        guibg = color_table.inactive_menu.gui,
+        ctermfg = color_table.alt_text.cterm,
+        ctermbg = color_table.inactive_menu.cterm,
+      },
+      inactive = inactive,
+    },
+    error = {
+      active = {
+        guifg = color_table.text.gui,
+        guibg = color_table.command.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.command.cterm,
+      },
+      inactive = inactive,
+    },
+    warning = {
+      active = {
+        guifg = color_table.text.gui,
+        guibg = color_table.warning.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.warning.cterm,
+      },
+      inactive = inactive,
+    },
+    bufferline = {
+      separator = inactive,
+      current = {
+        guifg = color_table.text.gui,
+        guibg = color_table.normal.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.normal.cterm,
+      },
+      current_modified = {
+        guifg = color_table.text.gui,
+        guibg = color_table.insert.gui,
+        ctermfg = color_table.text.cterm,
+        ctermbg = color_table.insert.cterm,
+      },
+      background = {
+        guifg = color_table.normal.gui,
+        guibg = color_table.text.gui,
+        ctermfg = color_table.normal.cterm,
+        ctermbg = color_table.text.cterm,
+      },
+      background_modified = {
+        guifg = color_table.insert.gui,
+        guibg = color_table.text.gui,
+        ctermfg = color_table.insert.cterm,
+        ctermbg = color_table.text.cterm,
+      },
+    },
+  }
+end
+
+return M