-- Highlight on yank
vim.api.nvim_create_autocmd("TextYankPost", {
    group = vim.api.nvim_create_augroup("highlight_yank", { clear = true }),
    callback = function()
        vim.hl.on_yank()
    end,
})

-- Buffer tab navigation (scoped to current window)
local function cycle_win_buf(dir)
    local bufs = _G.get_win_bufs()
    if #bufs <= 1 then return end
    local current = vim.api.nvim_get_current_buf()
    for i, buf in ipairs(bufs) do
        if buf == current then
            local next = bufs[((i - 1 + dir) % #bufs) + 1]
            vim.api.nvim_set_current_buf(next)
            return
        end
    end
end
vim.keymap.set("n", "<Tab>", function() cycle_win_buf(1) end, { desc = "Next buffer tab" })
vim.keymap.set("n", "<S-Tab>", function() cycle_win_buf(-1) end, { desc = "Previous buffer tab" })
vim.keymap.set("n", "<leader>x", function()
    local bufs = _G.get_win_bufs()
    local current = vim.api.nvim_get_current_buf()
    -- Switch to another buffer in this window, or create a blank one
    local switched = false
    for _, buf in ipairs(bufs) do
        if buf ~= current then
            vim.api.nvim_set_current_buf(buf)
            switched = true
            break
        end
    end
    if not switched then
        vim.cmd("enew")
        vim.bo.bufhidden = "wipe"
    end
    vim.cmd("bdelete " .. current)
end, { desc = "Close buffer tab" })


-- Splits duplicate current file (default Vim behavior)
vim.keymap.set("n", "<C-w>v", ":vsplit<CR>", { desc = "Vertical split" })
vim.keymap.set("n", "<C-w>s", ":split<CR>", { desc = "Horizontal split" })

-- Move between panes with Alt+h/l, wraps around (works in normal and terminal mode)
local function wrap_move(dir)
    local cur = vim.api.nvim_get_current_win()
    vim.cmd("wincmd " .. dir)
    if vim.api.nvim_get_current_win() == cur then
        -- Didn't move, wrap around
        local opposite = ({ h = "l", l = "h", j = "k", k = "j" })[dir]
        -- Go to the far opposite end
        vim.cmd("99wincmd " .. opposite)
    end
end
vim.keymap.set("n", "<A-h>", function() wrap_move("h") end, { desc = "Move to left pane (wrap)" })
vim.keymap.set("n", "<A-l>", function() wrap_move("l") end, { desc = "Move to right pane (wrap)" })
vim.keymap.set("n", "<A-j>", function() wrap_move("j") end, { desc = "Move to pane below (wrap)" })
vim.keymap.set("n", "<A-k>", function() wrap_move("k") end, { desc = "Move to pane above (wrap)" })
vim.keymap.set("t", "<A-h>", function() vim.cmd("stopinsert") wrap_move("h") end, { desc = "Move to left pane (wrap)" })
vim.keymap.set("t", "<A-l>", function() vim.cmd("stopinsert") wrap_move("l") end, { desc = "Move to right pane (wrap)" })
vim.keymap.set("t", "<A-j>", function() vim.cmd("stopinsert") wrap_move("j") end, { desc = "Move to pane below (wrap)" })
vim.keymap.set("t", "<A-k>", function() vim.cmd("stopinsert") wrap_move("k") end, { desc = "Move to pane above (wrap)" })

-- Floating popup terminal with tabs (toggle with <C-t>)
local popup_term = { bufs = {}, current = 1, win = nil }

local function ensure_term_buf(idx)
    if not popup_term.bufs[idx] or not vim.api.nvim_buf_is_valid(popup_term.bufs[idx]) then
        popup_term.bufs[idx] = vim.api.nvim_create_buf(false, true)
    end
    return popup_term.bufs[idx]
end

local function term_title()
    local parts = {}
    for i = 1, #popup_term.bufs do
        if not vim.api.nvim_buf_is_valid(popup_term.bufs[i]) then break end
        if i == popup_term.current then
            parts[#parts + 1] = "[" .. i .. "]"
        else
            parts[#parts + 1] = " " .. i .. " "
        end
    end
    return " Terminal " .. table.concat(parts) .. " "
end

local function open_popup_win(buf)
    local width = math.floor(vim.o.columns * 0.8)
    local height = math.floor(vim.o.lines * 0.75)
    popup_term.win = vim.api.nvim_open_win(buf, true, {
        relative = "editor",
        width = width,
        height = height,
        col = math.floor((vim.o.columns - width) / 2),
        row = math.floor((vim.o.lines - height) / 2) - 1,
        style = "minimal",
        border = "rounded",
        title = term_title(),
        title_pos = "center",
    })
end

local function update_title()
    if popup_term.win and vim.api.nvim_win_is_valid(popup_term.win) then
        vim.api.nvim_win_set_config(popup_term.win, { title = term_title() })
    end
end

local function switch_term(idx)
    if idx < 1 or idx > #popup_term.bufs then return end
    popup_term.current = idx
    local buf = ensure_term_buf(idx)
    if popup_term.win and vim.api.nvim_win_is_valid(popup_term.win) then
        vim.api.nvim_win_set_buf(popup_term.win, buf)
        update_title()
        if vim.bo[buf].buftype == "terminal" then
            vim.cmd.startinsert()
        end
    end
end

local function toggle_popup_term()
    if popup_term.win and vim.api.nvim_win_is_valid(popup_term.win) then
        vim.api.nvim_win_hide(popup_term.win)
        popup_term.win = nil
        return
    end

    local buf = ensure_term_buf(popup_term.current)
    open_popup_win(buf)

    if vim.bo[buf].buftype ~= "terminal" then
        vim.cmd.terminal()
    end
    vim.cmd.startinsert()
end

local function new_term_tab()
    local idx = #popup_term.bufs + 1
    ensure_term_buf(idx)
    popup_term.current = idx
    if popup_term.win and vim.api.nvim_win_is_valid(popup_term.win) then
        vim.api.nvim_win_set_buf(popup_term.win, popup_term.bufs[idx])
        update_title()
        vim.cmd.terminal()
        vim.cmd.startinsert()
    end
end

local function close_term_tab()
    if #popup_term.bufs <= 1 then return end
    local buf = popup_term.bufs[popup_term.current]
    table.remove(popup_term.bufs, popup_term.current)
    if popup_term.current > #popup_term.bufs then
        popup_term.current = #popup_term.bufs
    end
    switch_term(popup_term.current)
    if vim.api.nvim_buf_is_valid(buf) then
        vim.api.nvim_buf_delete(buf, { force = true })
    end
end

-- Init first tab
ensure_term_buf(1)

vim.keymap.set("n", "<C-t>", toggle_popup_term, { desc = "Toggle popup terminal" })
vim.keymap.set("t", "<C-t>", toggle_popup_term, { desc = "Toggle popup terminal" })
vim.keymap.set("t", "<A-]>", function() switch_term(popup_term.current % #popup_term.bufs + 1) end, { desc = "Next terminal tab" })
vim.keymap.set("t", "<A-[>", function() switch_term((popup_term.current - 2) % #popup_term.bufs + 1) end, { desc = "Prev terminal tab" })
vim.keymap.set("t", "<C-n>", new_term_tab, { desc = "New terminal tab" })
vim.keymap.set("t", "<C-w>", close_term_tab, { desc = "Close terminal tab" })

-- Terminal copy/paste
vim.keymap.set("t", "<C-v>", function()
    local reg = vim.fn.getreg("+")
    if reg ~= "" then
        vim.api.nvim_paste(reg, true, -1)
    end
end, { desc = "Paste from clipboard" })
vim.keymap.set("t", "<C-y>", [[<C-\><C-n>V]], { desc = "Select current line (normal mode)" })
vim.keymap.set("t", "<Esc>", [[<C-\><C-n>]], { desc = "Exit to normal mode" })

-- Save/restore layout with :mksession
vim.opt.sessionoptions = "buffers,curdir,folds,winpos,winsize,terminal"
vim.keymap.set("n", "<leader>ss", ":mksession! ~/.config/nvim/session.vim<CR>", { desc = "Save session/layout" })
vim.keymap.set("n", "<leader>sl", ":source ~/.config/nvim/session.vim<CR>", { desc = "Load session/layout" })

-- Trim trailing whitespace on save
vim.api.nvim_create_autocmd("BufWritePre", {
    group = vim.api.nvim_create_augroup("trim_whitespace", { clear = true }),
    pattern = "*",
    callback = function()
        local pos = vim.api.nvim_win_get_cursor(0)
        vim.cmd([[%s/\s\+$//e]])
        vim.api.nvim_win_set_cursor(0, pos)
    end,
})