vim.cmd('syntax on')

local function detect_background()
  vim.system(
    { 'defaults', 'read', '-g', 'AppleInterfaceStyle' },
    { text = true },
    function(out)
      local bg = (out.stdout or ''):match('Dark') and 'dark' or 'light'
      vim.schedule(function()
        if bg ~= vim.o.background then vim.o.background = bg end
      end)
    end
  )
end

-- All treesitter capture groups to neutralize
local TS_GROUPS = {
  '@variable', '@variable.builtin', '@variable.parameter', '@variable.member',
  '@module', '@module.builtin', '@label',
  '@string', '@string.documentation', '@string.escape', '@string.special',
  '@string.special.symbol', '@string.special.url',
  '@character', '@character.special',
  '@boolean', '@number', '@number.float', '@float',
  '@function', '@function.builtin', '@function.call', '@function.macro',
  '@function.method', '@function.method.call',
  '@constructor', '@operator',
  '@keyword', '@keyword.coroutine', '@keyword.function', '@keyword.operator',
  '@keyword.import', '@keyword.type', '@keyword.modifier', '@keyword.repeat',
  '@keyword.return', '@keyword.debug', '@keyword.exception',
  '@keyword.conditional', '@keyword.conditional.ternary',
  '@keyword.directive', '@keyword.directive.define',
  '@punctuation', '@punctuation.delimiter', '@punctuation.bracket', '@punctuation.special',
  '@type', '@type.builtin', '@type.definition',
  '@attribute', '@attribute.builtin', '@property',
  '@constant', '@constant.builtin', '@constant.macro',
  '@namespace', '@field', '@parameter',
  '@conditional', '@repeat', '@include', '@exception',
  '@tag', '@tag.builtin', '@tag.attribute', '@tag.delimiter',
  '@text', '@text.title', '@text.literal', '@text.reference',
  '@text.emphasis', '@text.strong', '@text.uri', '@text.strikethrough',
  '@text.todo', '@text.note', '@text.warning', '@text.danger',
  '@markup', '@markup.heading',
  '@markup.heading.1', '@markup.heading.2', '@markup.heading.3',
  '@markup.heading.4', '@markup.heading.5', '@markup.heading.6',
  '@markup.quote', '@markup.link', '@markup.link.label', '@markup.link.url',
  '@markup.raw', '@markup.raw.block', '@markup.list',
  '@markup.list.checked', '@markup.list.unchecked',
  '@markup.italic', '@markup.bold', '@markup.strikethrough',
  '@markup.underline', '@markup.math',
  '@diff.plus', '@diff.minus', '@diff.delta',
  -- LSP semantic tokens
  '@lsp.type.class', '@lsp.type.comment', '@lsp.type.decorator',
  '@lsp.type.enum', '@lsp.type.enumMember', '@lsp.type.event',
  '@lsp.type.function', '@lsp.type.interface', '@lsp.type.keyword',
  '@lsp.type.macro', '@lsp.type.method', '@lsp.type.modifier',
  '@lsp.type.namespace', '@lsp.type.number', '@lsp.type.operator',
  '@lsp.type.parameter', '@lsp.type.property', '@lsp.type.regexp',
  '@lsp.type.string', '@lsp.type.struct', '@lsp.type.type',
  '@lsp.type.typeParameter', '@lsp.type.variable',
  '@lsp.mod.abstract', '@lsp.mod.async', '@lsp.mod.declaration',
  '@lsp.mod.defaultLibrary', '@lsp.mod.definition', '@lsp.mod.deprecated',
  '@lsp.mod.documentation', '@lsp.mod.modification',
  '@lsp.mod.readonly', '@lsp.mod.static',
}

local SYNTAX_GROUPS = {
  'Statement', 'Keyword', 'Function', 'Type', 'PreProc', 'Special',
  'Identifier', 'Constant', 'String', 'Number', 'Boolean', 'Operator',
  'Title', 'Bold', 'Italic', 'Include', 'Define', 'Macro', 'Structure',
  'StorageClass', 'Typedef', 'Tag', 'Delimiter', 'SpecialComment', 'Todo',
}

local function apply()
  vim.cmd('hi clear')

  local is_dark    = vim.o.background == 'dark'
  -- icy palette
  local comment_fg = is_dark and '#6b635a' or '#776e63'  -- matches Zed comment color
  local subtle     = is_dark and '#4a443d' or '#fceccc'  -- borders, indent guides
  local sel_bg     = is_dark and '#509c93' or '#fceccc'  -- matches Ghostty selection
  local sel_fg     = is_dark and '#fff6e3' or '#4a443d'
  local active_bg  = is_dark and '#2a261f' or '#f5f0e6'  -- active line / pmenu bg

  -- Normal: transparent so Ghostty bg shows through
  vim.api.nvim_set_hl(0, 'Normal',   { bg = 'NONE', fg = 'NONE' })
  vim.api.nvim_set_hl(0, 'NormalNC', { bg = 'NONE', fg = 'NONE' })

  -- Comments: lighter + italic (only syntax highlight)
  vim.api.nvim_set_hl(0, 'Comment',                  { fg = comment_fg, italic = true })
  vim.api.nvim_set_hl(0, '@comment',                 { fg = comment_fg, italic = true })
  vim.api.nvim_set_hl(0, '@comment.documentation',   { fg = comment_fg, italic = true })

  -- Neutralize all treesitter and LSP semantic token groups
  for _, group in ipairs(TS_GROUPS) do
    vim.api.nvim_set_hl(0, group, {})
  end
  for _, group in ipairs(SYNTAX_GROUPS) do
    vim.api.nvim_set_hl(0, group, {})
  end

  -- Non-text / whitespace / indent guides
  vim.api.nvim_set_hl(0, 'Whitespace',   { fg = subtle })
  vim.api.nvim_set_hl(0, 'NonText',      { fg = subtle })
  vim.api.nvim_set_hl(0, 'EndOfBuffer',  { fg = subtle })
  vim.api.nvim_set_hl(0, 'SpecialKey',   { fg = subtle })

  -- Line numbers
  vim.api.nvim_set_hl(0, 'LineNr',       { fg = subtle })
  vim.api.nvim_set_hl(0, 'CursorLineNr', { fg = comment_fg })
  vim.api.nvim_set_hl(0, 'SignColumn',   { bg = 'NONE' })

  -- Cursor line (if cursorline is ever enabled)
  vim.api.nvim_set_hl(0, 'CursorLine',   { bg = active_bg })
  vim.api.nvim_set_hl(0, 'CursorColumn', { bg = active_bg })

  -- Selection / search: match Ghostty selection colors
  vim.api.nvim_set_hl(0, 'Visual',      { bg = sel_bg, fg = sel_fg })
  vim.api.nvim_set_hl(0, 'Search',      { bg = sel_bg, fg = sel_fg })
  vim.api.nvim_set_hl(0, 'IncSearch',   { bg = sel_bg, fg = sel_fg })
  vim.api.nvim_set_hl(0, 'CurSearch',   { bg = sel_bg, fg = sel_fg })
  vim.api.nvim_set_hl(0, 'Substitute',  { bg = sel_bg, fg = sel_fg })

  -- Matching parens: subtle underline, no color
  vim.api.nvim_set_hl(0, 'MatchParen', { underline = true })

  -- Popup menu
  vim.api.nvim_set_hl(0, 'Pmenu',      { bg = active_bg })
  vim.api.nvim_set_hl(0, 'PmenuSel',   { bg = sel_bg, fg = sel_fg })
  vim.api.nvim_set_hl(0, 'PmenuSbar',  { bg = subtle })
  vim.api.nvim_set_hl(0, 'PmenuThumb', { bg = comment_fg })

  -- Window / float borders
  vim.api.nvim_set_hl(0, 'WinSeparator', { fg = subtle })
  vim.api.nvim_set_hl(0, 'VertSplit',    { fg = subtle })
  vim.api.nvim_set_hl(0, 'NormalFloat',  { bg = 'NONE', fg = 'NONE' })
  vim.api.nvim_set_hl(0, 'FloatBorder',  { fg = comment_fg })

  -- Status / tab line: transparent
  vim.api.nvim_set_hl(0, 'StatusLine',   { bg = 'NONE', fg = 'NONE' })
  vim.api.nvim_set_hl(0, 'StatusLineNC', { bg = 'NONE', fg = 'NONE' })
  vim.api.nvim_set_hl(0, 'TabLine',      { bg = 'NONE', fg = comment_fg })
  vim.api.nvim_set_hl(0, 'TabLineSel',   { bg = 'NONE', fg = 'NONE' })
  vim.api.nvim_set_hl(0, 'TabLineFill',  { bg = 'NONE' })

  -- Folds
  vim.api.nvim_set_hl(0, 'Folded',     { fg = comment_fg })
  vim.api.nvim_set_hl(0, 'FoldColumn', { fg = subtle, bg = 'NONE' })

  -- Diff: icy palette tinted bgs, no fg colors (monochrome)
  if is_dark then
    vim.api.nvim_set_hl(0, 'DiffAdd',    { bg = '#1a2a10' })
    vim.api.nvim_set_hl(0, 'DiffDelete', { bg = '#2d1616' })
    vim.api.nvim_set_hl(0, 'DiffChange', { bg = '#0f2525' })
    vim.api.nvim_set_hl(0, 'DiffText',   { bg = '#1a3a38' })
    vim.api.nvim_set_hl(0, 'diffAdded',   { fg = '#7c9f4b' })
    vim.api.nvim_set_hl(0, 'diffRemoved', { fg = '#db7070' })
    vim.api.nvim_set_hl(0, 'diffChanged', { fg = '#509c93' })
  else
    vim.api.nvim_set_hl(0, 'DiffAdd',    { bg = '#e8f3d8' })
    vim.api.nvim_set_hl(0, 'DiffDelete', { bg = '#f9e0e0' })
    vim.api.nvim_set_hl(0, 'DiffChange', { bg = '#daf0ed' })
    vim.api.nvim_set_hl(0, 'DiffText',   { bg = '#b8e0dc' })
    vim.api.nvim_set_hl(0, 'diffAdded',   { fg = '#7c9f4b' })
    vim.api.nvim_set_hl(0, 'diffRemoved', { fg = '#db7070' })
    vim.api.nvim_set_hl(0, 'diffChanged', { fg = '#509c93' })
  end

  -- Diagnostics: underline only, signs/virtual text in comment color
  for _, kind in ipairs({ 'Error', 'Warn', 'Info', 'Hint' }) do
    vim.api.nvim_set_hl(0, 'Diagnostic' .. kind,                { fg = comment_fg })
    vim.api.nvim_set_hl(0, 'DiagnosticUnderline' .. kind,       { underline = true })
    vim.api.nvim_set_hl(0, 'DiagnosticVirtualText' .. kind,     { fg = comment_fg })
    vim.api.nvim_set_hl(0, 'DiagnosticSign' .. kind,            { fg = comment_fg })
    vim.api.nvim_set_hl(0, 'DiagnosticFloating' .. kind,        { fg = comment_fg })
  end

  -- Spell: underline only
  for _, kind in ipairs({ 'Bad', 'Cap', 'Rare', 'Local' }) do
    vim.api.nvim_set_hl(0, 'Spell' .. kind, { underline = true, sp = comment_fg })
  end

  -- Git signs (gitsigns): icy palette colors
  vim.api.nvim_set_hl(0, 'GitSignsAdd',    { fg = '#7c9f4b' })
  vim.api.nvim_set_hl(0, 'GitSignsChange', { fg = '#509c93' })
  vim.api.nvim_set_hl(0, 'GitSignsDelete', { fg = '#db7070' })
end

detect_background()
apply()

vim.api.nvim_create_autocmd('OptionSet',   { pattern = 'background', callback = apply })
vim.api.nvim_create_autocmd('FocusGained', { callback = detect_background })
vim.api.nvim_create_autocmd('VimEnter',    { once = true, callback = apply })

-- Re-clear LSP semantic tokens after LspAttach (set after colorscheme loads)
vim.api.nvim_create_autocmd('LspAttach', {
  callback = function()
    for _, group in ipairs(vim.fn.getcompletion('@lsp', 'highlight')) do
      if not group:match('comment') then
        vim.api.nvim_set_hl(0, group, {})
      end
    end
  end,
})