local M = {}

function M.get(spec, config)

local syn = spec.syntax

local stl = config.styles

---Clears nvim's default highlighting for a highlight-group and allows

---falling-back to another hl-group when multiple highlights/groups are

---assigned/stacked at a particular screen position. This is just an empty

---table.

---

---NOTE: assigning this to a group is different from explicitly setting a

---group's foreground color to the global/default foreground color. When

---multiple highlights are stacked/assigned to the same screen position, this

---will allow the other highlights/groups to take effect, whereas explicitly

---setting a hl-group's `fg` will not.

---

---| Setting | Fallback |

---| ------------------------------------------------------------ | -------- |

---| `GROUP = FALLBACK_OR_NONE` (i.e. set to this variable) (Lua) | true |

---| Link to `@none`, `Fg`, or `NONE` | true |

---| `GROUP = { fg = DEFAULT_FG }` (Lua) | false |

---| `hi! clear GROUP` (Vim command) | false |

---| `hi! GROUP NONE` (Vim command) | false |

local FALLBACK_OR_NONE = setmetatable({}, {

__newindex = function()

error('attempt to set index of readonly table', 2)

end,

})

-- TODO:

-- (1) add Commented style settings in config module

-- stylua: ignore

return {

Comment = { fg = syn.comment, style = stl.comments, nocombine = true }, -- any comment

Constant = { fg = syn.const, style = stl.constants }, -- (preferred) any constant

String = { fg = syn.string, style = stl.strings }, -- a string constant: 'this is a string'

Character = { link = 'String' }, -- a character constant: 'c', '\n'

Number = { fg = syn.number, style = stl.numbers }, -- a number constant: 234, 0xff

Float = { link = 'Number' }, -- a floating point constant: 2.3e10

Boolean = { link = 'Number' }, -- a boolean constant: TRUE, false

Identifier = { fg = syn.ident, style = stl.variables }, -- (preferred) any variable name

Function = { fg = syn.func, style = stl.functions }, -- function name (also: methods for classes)

Statement = { fg = syn.keyword, style = stl.keywords }, -- (preferred) any statement

Conditional = { fg = syn.conditional, style = stl.conditionals }, -- if, then, else, endif, switch, etc.

Repeat = { link = 'Conditional' }, -- for, do, while, etc.

Label = { link = 'Conditional' }, -- case, default, etc.

Operator = { fg = syn.operator, style = stl.operators }, -- 'sizeof', '+', '*', etc.

Keyword = { fg = syn.keyword, style = stl.keywords }, -- any other keyword

Exception = { link = 'Keyword' }, -- try, catch, throw

PreProc = { fg = syn.preproc }, -- (preferred) generic Preprocessor

Include = { link = 'PreProc' }, -- preprocessor #include

Define = { link = 'PreProc' }, -- preprocessor #define

Macro = { link = 'PreProc' }, -- same as Define

PreCondit = { link = 'PreProc' }, -- preprocessor #if, #else, #endif, etc.

Type = { fg = syn.type, style = stl.types }, -- (preferred) int, long, char, etc.

StorageClass = { link = 'Type' }, -- static, register, volatile, etc.

Structure = { link = 'Type' }, -- struct, union, enum, etc.

Typedef = { link = 'Type' }, -- A typedef

Special = { fg = spec.fg1 }, -- (preferred) any special symbol

SpecialChar = { link = 'Special' }, -- special character in a constant

Tag = { link = 'Special' }, -- you can use CTRL-] on this

Delimiter = { link = 'Special' }, -- character that needs attention

SpecialComment = { link = 'Special' }, -- special things inside a comment

Debug = { link = 'Special' }, -- debugging statements

Underlined = { style = 'underline' }, -- (preferred) text that stands out, HTML links

Bold = { style = 'bold' },

Italic = { style = 'italic' },

-- ('Ignore', below, may be invisible...)

-- Ignore = {}, -- (preferred) left blank, hidden |hl-Ignore|

Error = { fg = spec.diag.error }, -- (preferred) any erroneous construct

Todo = { fg = spec.bg1, bg = spec.diag.info }, -- (preferred) anything that needs extra attention; mostly the keywords TODO FIXME and XXX

qfLineNr = { link = 'lineNr' },

qfFileName = { link = 'Directory' },

htmlTag = { fg = syn.tag },

-- htmlH1 = {},

-- htmlH2 = {},

xmlAttrib = { link ='htmlTag' },

xmlTagName = { link ='htmlTag' },

cssBraces = { fg = syn.bracket },

cssMedia = { link = 'Keyword' },

cssProp = { link = 'Constant' },

cssPseudoClassId = { link = 'Function' },

lessAmpersand = { link = 'Function' },

lessClass = { link = 'Function' },

lessClassCall = { link = 'Function' },

lessCssAttribute = { link = 'Constant' },

lessFunction = { link = 'Constant' },

lessVariable = { fg = spec.fg1 },

-- mkdHeading = {},

-- mkdCode = {},

-- mkdCodeDelimiter = {},

-- mkdCodeStart = {},

-- mkdCodeEnd = {},

-- mkdLink = {},

-- markdownHeadingDelimiter = {},

-- markdownCode = {},

-- markdownCodeBlock = {},

-- markdownH1 = {},

-- markdownH2 = {},

-- markdownLinkText = {},

-- Diff filetype (runtime/syntax/diff.vim)

Added = { fg = spec.git.add, bg = spec.diff.add }, -- added line in a diff

Changed = { fg = spec.git.changed, bg = spec.diff.change }, -- changed line in a diff

Removed = { fg = spec.git.removed, bg = spec.diff.delete },-- removed line in a diff

diffAdded = { link = 'Added' }, -- Added lines ('^+.*' | '^>.*')

diffChanged = { link = 'Changed' }, -- Changed lines ('^! .*')

diffRemoved = { link = 'Removed' },-- Removed lines ('^-.*' | '^<.*')

diffOldFile = { fg = spec.diag.warn }, -- Old file that is being diff against

diffNewFile = { fg = spec.diag.hint }, -- New file that is being compared to the old file

diffFile = { fg = spec.diag.info }, -- The filename of the diff ('diff --git a/readme.md b/readme.md')

diffLine = { fg = syn.builtin2 }, -- Line information ('@@ -169,6 +169,9 @@')

diffIndexLine = { fg = syn.preproc }, -- Index line of diff ('index bf3763d..94f0f62 100644')

-- Language specific -------------------------------------------------------

-- Json

jsonKeyword = { fg = syn.tag }, -- Json keys (e.g. `"key": "value"`)

jsonNull = { link = 'Constant' },

-- Lua

luaFunction = { link = 'Keyword' }, -- Function keywords (`function`, `end`) (corrects upstream inaccuracy/bug)

luaTable = FALLBACK_OR_NONE, -- Table brackets (`{}`)

-- Yaml

yamlBlockMappingKey = { fg = syn.tag },

yamlFlowMappingKey = { fg = syn.tag },

}

end

return M