init.lua

-- Neovim Configuration
-- Basic UI Settings
vim.opt.number = true           -- Show line numbers
vim.opt.shiftwidth = 4          -- Set indentation to 4 spaces
vim.opt.tabstop = 4             -- Set tab width to 4 spaces
vim.opt.expandtab = true        -- Use spaces instead of tabs
vim.opt.autoindent = true       -- Enable auto indentation
vim.opt.smartindent = true      -- Enable smart indentation

-- Search Settings
vim.opt.incsearch = true        -- Enable incremental search
vim.opt.hlsearch = true         -- Highlight search results

-- Status Line Configuration
vim.opt.laststatus = 2          -- Always show statusline
vim.opt.showmode = false        -- Hide default mode indicator (since it's in our statusline)
vim.opt.ruler = true            -- Show cursor position

-- Define colors for different modes
local colors = {
    normal = "StatusLineNormal",
    insert = "StatusLineInsert",
    visual = "StatusLineVisual",
    visual_block = "StatusLineVisualBlock",
    replace = "StatusLineReplace",
    command = "StatusLineCommand",
    terminal = "StatusLineTerminal"
}

-- Create highlight groups for different modes
local function set_highlights()
    vim.api.nvim_set_hl(0, "StatusLineNormal", { bg = "white", fg = "black" })
    vim.api.nvim_set_hl(0, "StatusLineInsert", { bg = "blue", fg = "white" })
    vim.api.nvim_set_hl(0, "StatusLineVisual", { bg = "green", fg = "black" })
    vim.api.nvim_set_hl(0, "StatusLineVisualBlock", { bg = "orange", fg = "black" })
    vim.api.nvim_set_hl(0, "StatusLineReplace", { bg = "red", fg = "white" })
    vim.api.nvim_set_hl(0, "StatusLineCommand", { bg = "purple", fg = "white" })
    vim.api.nvim_set_hl(0, "StatusLineTerminal", { bg = "cyan", fg = "black" })
end

-- Call the function to set highlights
set_highlights()

-- Function to update statusline based on mode
local function update_statusline()
    local mode = vim.api.nvim_get_mode().mode
    local highlight = colors.normal
    local mode_text = "NORMAL"
    
    if mode == "n" then
        highlight = colors.normal
        mode_text = "NORMAL"
    elseif mode == "i" then
        highlight = colors.insert
        mode_text = "INSERT"
    elseif mode == "v" then
        highlight = colors.visual
        mode_text = "VISUAL"
    elseif mode == "V" then
        highlight = colors.visual
        mode_text = "VISUAL LINE"
    elseif mode == "\22" then  -- ^V, visual block mode
        highlight = colors.visual_block
        mode_text = "VISUAL BLOCK"
    elseif mode == "R" then
        highlight = colors.replace
        mode_text = "REPLACE"
    elseif mode == "c" then
        highlight = colors.command
        mode_text = "COMMAND"
    elseif mode == "t" then
        highlight = colors.terminal
        mode_text = "TERMINAL"
    end
    
    local statusline = "%#" .. highlight .. "#"
    statusline = statusline .. " " .. mode_text .. " %="
    statusline = statusline .. " %f | %y | %l:%c | %p%% "
    
    vim.opt.statusline = statusline
end

-- Create autocommand to update statusline when mode changes
vim.api.nvim_create_autocmd({"ModeChanged"}, {
    pattern = "*",
    callback = function()
        update_statusline()
    end,
})

-- Create autocommand to update statusline when entering a buffer
vim.api.nvim_create_autocmd({"BufEnter", "VimEnter"}, {
    pattern = "*",
    callback = function()
        update_statusline()
    end,
})

-- Initial statusline setup
update_statusline()

-- Key Mappings
-- Clear search highlighting with <Esc><Esc>
vim.keymap.set('n', '<Esc><Esc>', ':nohlsearch<CR>', { silent = true })

-- Other Recommended Settings (commented out)
-- ----------------------------------------

-- Enable mouse support for all modes
-- vim.opt.mouse = 'a'

-- Enable true color support for terminals that support it
vim.opt.termguicolors = true

-- Set line at 80 characters to help with code formatting
-- vim.opt.colorcolumn = '80'

-- Show matching brackets/parentheses
vim.opt.showmatch = true

-- Enable persistent undo history
vim.opt.undofile = true
vim.opt.undodir = vim.fn.stdpath('data') .. '/undodir'

-- Disable swap files (reduces clutter in project directories)
-- vim.opt.swapfile = false

-- Better splitting behavior (open new splits below and to the right)
-- vim.opt.splitbelow = true
-- vim.opt.splitright = true

-- Set scroll offset to keep cursor from edges
-- vim.opt.scrolloff = 8
-- vim.opt.sidescrolloff = 8

-- Case-insensitive searching UNLESS capital letter included
vim.opt.ignorecase = true
vim.opt.smartcase = true

-- Auto reload files when changed outside of Neovim
vim.opt.autoread = true
vim.api.nvim_create_autocmd({ "FocusGained", "BufEnter" }, {
  pattern = "*",
  command = "checktime",
})

-- Enable folding based on indentation
-- vim.opt.foldmethod = 'indent'
-- vim.opt.foldlevelstart = 99  -- Start with all folds open