-- Plugins
local lazypath = vim.fn.stdpath("data") .. "/lazy/lazy.nvim"
if not vim.loop.fs_stat(lazypath) then
    vim.fn.system({
        "git", "clone", "--filter=blob:none",
        "https://github.com/folke/lazy.nvim.git",
        "--branch=stable", lazypath,
    })
end
vim.opt.rtp:prepend(lazypath)

require("lazy").setup({
    {
        'nvim-telescope/telescope.nvim',
        dependencies = {
            'nvim-lua/plenary.nvim',
            { 'nvim-telescope/telescope-fzf-native.nvim', build = 'make' },
        },
        keys = {
            { '<leader>ff', '<cmd>Telescope find_files<cr>' },
            { '<leader>fg', '<cmd>Telescope live_grep<cr>' },
            { '<leader>fb', '<cmd>Telescope buffers<cr>' },
        },
    },
    {
        "rcarriga/nvim-dap-ui",
        dependencies = { "mfussenegger/nvim-dap", "nvim-neotest/nvim-nio" },
    },
    {
        'lewis6991/gitsigns.nvim',
        event = { 'BufReadPre', 'BufNewFile' },
        opts = {
            signs = {
                add          = { text = '+' },
                change       = { text = '~' },
                delete       = { text = '_' },
                topdelete    = { text = '-' },
                changedelete = { text = '~' },
            },
        },
    },
    {
        "iamcco/markdown-preview.nvim",
        cmd = { "MarkdownPreviewToggle", "MarkdownPreview", "MarkdownPreviewStop" },
        build = "cd app && npm install",
        init = function()
            vim.g.mkdp_filetypes = { "markdown" }
        end,
        ft = { "markdown" },
    },
})

-- theme & transparency
vim.cmd.colorscheme("unokai")
vim.api.nvim_set_hl(0, "Normal", { bg = "none" })
vim.api.nvim_set_hl(0, "NormalNC", { bg = "none" })
vim.api.nvim_set_hl(0, "EndOfBuffer", { bg = "none" })

-- Basic settings
vim.opt.number = true         -- Line numbers
vim.opt.relativenumber = true -- Relative line numbers
vim.opt.cursorline = true     -- Highlight current line
vim.opt.wrap = false          -- Don't wrap lines
vim.opt.scrolloff = 10        -- Keep 10 lines above/below cursor
vim.opt.list = true           -- Enable list mode for overflow indicators
vim.opt.listchars = { extends = '…', precedes = '…', tab = '  ' }
vim.opt.sidescrolloff = 1     -- Keep 1 column for the overflow indicator

-- Indentation
vim.opt.tabstop = 2        -- Tab width
vim.opt.shiftwidth = 2     -- Indent width
vim.opt.softtabstop = 2    -- Soft tab stop
vim.opt.expandtab = true   -- Use spaces instead of tabs
vim.opt.smartindent = true -- Smart auto-indenting
vim.opt.autoindent = true  -- Copy indent from current line

-- Search settings
vim.opt.ignorecase = true -- Case insensitive search
vim.opt.smartcase = true  -- Case sensitive if uppercase in search
vim.opt.hlsearch = true   -- Highlight search results
vim.opt.incsearch = true  -- Show matches as you type

-- Visual settings
vim.opt.termguicolors = true                      -- Enable 24-bit colors
vim.opt.signcolumn = "yes"                        -- Always show sign column
vim.opt.colorcolumn = "100"                       -- Show column at 100 characters
vim.opt.showmatch = true                          -- Highlight matching brackets
vim.opt.matchtime = 2                             -- How long to show matching bracket
vim.opt.cmdheight = 1                             -- Command line height
vim.opt.completeopt = "menuone,noinsert,noselect" -- Completion options
vim.opt.showmode = false                          -- Don't show mode in command line
vim.opt.pumheight = 10                            -- Popup menu height
vim.opt.pumblend = 10                             -- Popup menu transparency
vim.opt.winblend = 0                              -- Floating window transparency
vim.opt.conceallevel = 0                          -- Don't hide markup
vim.opt.concealcursor = ""                        -- Don't hide cursor line markup
vim.opt.lazyredraw = true                         -- Don't redraw during macros
vim.opt.synmaxcol = 300                           -- Syntax highlighting limit

-- File handling
vim.opt.backup = false                            -- Don't create backup files
vim.opt.writebackup = false                       -- Don't create backup before writing
vim.opt.swapfile = false                          -- Don't create swap files
vim.opt.undofile = true                           -- Persistent undo
vim.opt.undodir = vim.fn.expand("~/.vim/undodir") -- Undo directory
vim.opt.updatetime = 300                          -- Faster completion
vim.opt.timeoutlen = 500                          -- Key timeout duration
vim.opt.ttimeoutlen = 0                           -- Key code timeout
vim.opt.autoread = true                           -- Auto reload files changed outside vim
vim.opt.autowrite = false                         -- Don't auto save

-- Behavior settings
vim.opt.hidden = true                   -- Allow hidden buffers
vim.opt.errorbells = false              -- No error bells
vim.opt.backspace = "indent,eol,start"  -- Better backspace behavior
vim.opt.autochdir = false               -- Don't auto change directory
vim.opt.iskeyword:append("-")           -- Treat dash as part of word
vim.opt.path:append("**")               -- include subdirectories in search
vim.opt.selection = "exclusive"         -- Selection behavior
vim.opt.mouse = "a"                     -- Enable mouse support
vim.opt.clipboard:append("unnamedplus") -- Use system clipboard
vim.opt.modifiable = true               -- Allow buffer modifications
vim.opt.encoding = "UTF-8"              -- Set encoding

-- Cursor settings
vim.opt.guicursor =
"n-v-c:block,i-ci-ve:block,r-cr:hor20,o:hor50,a:blinkwait700-blinkoff400-blinkon250-Cursor/lCursor,sm:block-blinkwait175-blinkoff150-blinkon175"

-- Normal mode mappings
vim.keymap.set("n", "<leader>c", ":nohlsearch<CR>", { desc = "Clear search highlights" })

-- Delete without yanking
vim.keymap.set({ "n", "v" }, "<leader>d", '"_d', { desc = "Delete without yanking" })


-- Move lines up/down
vim.keymap.set("n", "<A-j>", ":m .+1<CR>==", { desc = "Move line down" })
vim.keymap.set("n", "<A-k>", ":m .-2<CR>==", { desc = "Move line up" })
vim.keymap.set("v", "<A-j>", ":m '>+1<CR>gv=gv", { desc = "Move selection down" })
vim.keymap.set("v", "<A-k>", ":m '<-2<CR>gv=gv", { desc = "Move selection up" })

-- Better indenting in visual mode
vim.keymap.set("v", "<", "<gv", { desc = "Indent left and reselect" })
vim.keymap.set("v", ">", ">gv", { desc = "Indent right and reselect" })

-- Quick file navigation
vim.keymap.set("n", "<leader>e", ":Explore<CR>", { desc = "Open file explorer" })

-- Netrw: h/l to navigate directory tree
vim.api.nvim_create_autocmd("FileType", {
    group = augroup,
    pattern = "netrw",
    callback = function()
        local opts = { buffer = true, remap = true }
        vim.keymap.set("n", "h", "-", opts)    -- go up a directory
        vim.keymap.set("n", "l", "<CR>", opts) -- open file/directory
    end,
})

-- Better J behavior
vim.keymap.set("n", "J", "mzJ`z", { desc = "Join lines and keep cursor position" })

-- ============================================================================
-- USEFUL FUNCTIONS
-- ============================================================================

-- Copy Full File-Path
vim.keymap.set("n", "<leader>pa", function()
    local path = vim.fn.expand("%:p")
    vim.fn.setreg("+", path)
    print("file:", path)
end)

-- Basic autocommands
local augroup = vim.api.nvim_create_augroup("UserConfig", {})

-- Highlight yanked text
vim.api.nvim_create_autocmd("TextYankPost", {
    group = augroup,
    callback = function()
        vim.highlight.on_yank()
    end,
})

-- Return to last edit position when opening files
vim.api.nvim_create_autocmd("BufReadPost", {
    group = augroup,
    callback = function()
        local mark = vim.api.nvim_buf_get_mark(0, '"')
        local lcount = vim.api.nvim_buf_line_count(0)
        if mark[1] > 0 and mark[1] <= lcount then
            pcall(vim.api.nvim_win_set_cursor, 0, mark)
        end
    end,
})

-- Set filetype-specific settings
vim.api.nvim_create_autocmd("FileType", {
    group = augroup,
    pattern = { "lua", "python" },
    callback = function()
        vim.opt_local.tabstop = 4
        vim.opt_local.shiftwidth = 4
    end,
})

vim.api.nvim_create_autocmd("FileType", {
    group = augroup,
    pattern = { "javascript", "typescript", "json", "html", "css" },
    callback = function()
        vim.opt_local.tabstop = 2
        vim.opt_local.shiftwidth = 2
    end,
})

-- Auto-close terminal when process exits
vim.api.nvim_create_autocmd("TermClose", {
    group = augroup,
    callback = function()
        if vim.v.event.status == 0 then
            vim.api.nvim_buf_delete(0, {})
        end
    end,
})

-- Disable line numbers in terminal
vim.api.nvim_create_autocmd("TermOpen", {
    group = augroup,
    callback = function()
        vim.opt_local.number = false
        vim.opt_local.relativenumber = false
        vim.opt_local.signcolumn = "no"
    end,
})

-- Create directories when saving files
vim.api.nvim_create_autocmd("BufWritePre", {
    group = augroup,
    callback = function()
        local dir = vim.fn.expand('<afile>:p:h')
        if vim.fn.isdirectory(dir) == 0 then
            vim.fn.mkdir(dir, 'p')
        end
    end,
})

-- Command-line completion
vim.opt.wildmenu = true
vim.opt.wildmode = "longest:full,full"
vim.opt.wildignore:append({ "*.o", "*.obj", "*.pyc", "*.class", "*.jar" })

-- Better diff options
vim.opt.diffopt:append("linematch:60")

-- Performance improvements
vim.opt.redrawtime = 10000
vim.opt.maxmempattern = 20000

-- Create undo directory if it doesn't exist
local undodir = vim.fn.expand("~/.vim/undodir")
if vim.fn.isdirectory(undodir) == 0 then
    vim.fn.mkdir(undodir, "p")
end

-- ============================================================================
-- STATUSLINE
-- ============================================================================

local function statusline_mode()
    local modes = {
        n = "NORMAL",
        i = "INSERT",
        v = "VISUAL",
        V = "V-LINE",
        ["\22"] = "V-BLOCK",
        c = "COMMAND",
        R = "REPLACE",
    }
    return modes[vim.fn.mode()] or vim.fn.mode():upper()
end

local function statusline_branch()
    local branch = vim.b.gitsigns_head
    if branch and branch ~= "" then return " " .. branch end
    return ""
end

_G.statusline_mode = statusline_mode
_G.statusline_branch = statusline_branch

vim.api.nvim_set_hl(0, "StatusLineBold", { bold = true })

vim.api.nvim_create_autocmd({ "WinEnter", "BufEnter" }, {
    callback = function()
        vim.opt_local.statusline =
            " %#StatusLineBold#%{v:lua.statusline_mode()}%#StatusLine#" ..
            " %f%m%r%{v:lua.statusline_branch()}" ..
            "%=" ..
            "%y %l:%c %P "
    end
})

vim.api.nvim_create_autocmd({ "WinLeave", "BufLeave" }, {
    callback = function()
        vim.opt_local.statusline = " %f%m%r%= %l:%c %P "
    end
})

-- ============================================================================
-- LSP
-- ============================================================================

-- Function to find project root
local function find_root(patterns)
    local path = vim.fn.expand('%:p:h')
    local root = vim.fs.find(patterns, { path = path, upward = true })[1]
    return root and vim.fn.fnamemodify(root, ':h') or path
end

-- Shell LSP setup
local function setup_shell_lsp()
    vim.lsp.start({
        name = 'bashls',
        cmd = { 'bash-language-server', 'start' },
        filetypes = { 'sh', 'bash', 'zsh' },
        root_dir = find_root({ '.git', 'Makefile' }),
        settings = {
            bashIde = {
                globPattern = "*@(.sh|.inc|.bash|.command)"
            }
        }
    })
end

-- Python LSP setup
local function setup_python_lsp()
    vim.lsp.start({
        name = 'pylsp',
        cmd = { 'pylsp' },
        filetypes = { 'python' },
        root_dir = find_root({ 'pyproject.toml', 'setup.py', 'setup.cfg', 'requirements.txt', '.git' }),
        settings = {
            pylsp = {
                plugins = {
                    pycodestyle = {
                        enabled = false
                    },
                    flake8 = {
                        enabled = true,
                    },
                    black = {
                        enabled = true
                    }
                }
            }
        }
    })
end

-- C/C++ LSP setup (clangd)
local function setup_clangd()
    vim.lsp.start({
        name = 'clangd',
        cmd = { 'clangd', '--background-index' },
        root_dir = find_root({ 'compile_commands.json', 'CMakeLists.txt', 'Makefile', '.git' }),
    })
end

-- Rust LSP setup (rust-analyzer)
local function setup_rust_analyzer()
    vim.lsp.start({
        name = 'rust-analyzer',
        cmd = { 'rust-analyzer' },
        root_dir = find_root({ 'Cargo.toml', '.git' }),
        settings = {
            ['rust-analyzer'] = {
                check = { command = 'clippy' },
            }
        }
    })
end

-- Auto-start LSPs based on filetype
vim.api.nvim_create_autocmd('FileType', {
    pattern = 'sh,bash,zsh',
    callback = setup_shell_lsp,
    desc = 'Start shell LSP'
})

vim.api.nvim_create_autocmd('FileType', {
    pattern = 'python',
    callback = setup_python_lsp,
    desc = 'Start Python LSP'
})

vim.api.nvim_create_autocmd('FileType', {
    pattern = 'c,cpp',
    callback = setup_clangd,
    desc = 'Start clangd LSP'
})

vim.api.nvim_create_autocmd('FileType', {
    pattern = 'rust',
    callback = setup_rust_analyzer,
    desc = 'Start rust-analyzer LSP'
})

-- formatting
local function format_code()
    local bufnr = vim.api.nvim_get_current_buf()
    local filename = vim.api.nvim_buf_get_name(bufnr)
    local filetype = vim.bo[bufnr].filetype

    -- Save cursor position
    local cursor_pos = vim.api.nvim_win_get_cursor(0)

    if filetype == 'python' or filename:match('%.py$') then
        if filename == '' then
            print("Save the file first before formatting Python")
            return
        end

        local black_cmd = "black --quiet " .. vim.fn.shellescape(filename)
        local black_result = vim.fn.system(black_cmd)

        if vim.v.shell_error == 0 then
            vim.cmd('checktime')
            vim.api.nvim_win_set_cursor(0, cursor_pos)
            print("Formatted with black")
            return
        else
            print("No Python formatter available (install black)")
            return
        end
    end

    if filetype == 'sh' or filetype == 'bash' or filename:match('%.sh$') then
        local lines = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
        local content = table.concat(lines, '\n')

        local cmd = { 'shfmt', '-i', '2', '-ci', '-sr' } -- 2 spaces, case indent, space redirects
        local result = vim.fn.system(cmd, content)

        if vim.v.shell_error == 0 then
            local formatted_lines = vim.split(result, '\n')
            if formatted_lines[#formatted_lines] == '' then
                table.remove(formatted_lines)
            end
            vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, formatted_lines)
            vim.api.nvim_win_set_cursor(0, cursor_pos)
            print("Shell script formatted with shfmt")
            return
        else
            print("shfmt error: " .. result)
            return
        end
    end

    print("No formatter available for " .. filetype)
end

vim.api.nvim_create_user_command("FormatCode", format_code, {
    desc = "Format current file"
})

vim.keymap.set('n', '<leader>fm', format_code, { desc = 'Format file' })

-- LSP keymaps
vim.api.nvim_create_autocmd('LspAttach', {
    callback = function(event)
        local opts = { buffer = event.buf }

        -- Navigation
        vim.keymap.set('n', 'gD', vim.lsp.buf.definition, opts)
        vim.keymap.set('n', 'gs', vim.lsp.buf.declaration, opts)
        vim.keymap.set('n', 'gr', vim.lsp.buf.references, opts)
        vim.keymap.set('n', 'gi', vim.lsp.buf.implementation, opts)

        -- Information
        vim.keymap.set('n', 'K', vim.lsp.buf.hover, opts)
        vim.keymap.set('n', '<C-k>', vim.lsp.buf.signature_help, opts)

        -- Code actions
        vim.keymap.set('n', '<leader>ca', vim.lsp.buf.code_action, opts)
        vim.keymap.set('n', '<leader>rn', vim.lsp.buf.rename, opts)

        -- Diagnostics
        vim.keymap.set('n', '<leader>nd', vim.diagnostic.goto_next, opts)
        vim.keymap.set('n', '<leader>pd', vim.diagnostic.goto_prev, opts)
        vim.keymap.set('n', '<leader>d', vim.diagnostic.open_float, opts)
        vim.keymap.set('n', '<leader>q', vim.diagnostic.setloclist, opts)
    end,
})

-- Better LSP UI
vim.diagnostic.config({
    virtual_text = { prefix = '●' },
    signs = true,
    underline = true,
    update_in_insert = false,
    severity_sort = true,
})

vim.diagnostic.config({
    signs = {
        text = {
            [vim.diagnostic.severity.ERROR] = "✗",
            [vim.diagnostic.severity.WARN] = "⚠",
            [vim.diagnostic.severity.INFO] = "ℹ",
            [vim.diagnostic.severity.HINT] = "💡",
        }
    }
})

vim.api.nvim_create_user_command('LspInfo', function()
    local clients = vim.lsp.get_clients({ bufnr = 0 })
    if #clients == 0 then
        print("No LSP clients attached to current buffer")
    else
        for _, client in ipairs(clients) do
            print("LSP: " .. client.name .. " (ID: " .. client.id .. ")")
        end
    end
end, { desc = 'Show LSP client info' })