local cmp = require("cmp")

local skkeleton = require("rc.skkeleton")
local ui = require("rc.ui")

local opts = {}

opts.enabled = function()
    if skkeleton.is_enabled() then
        return false
    end
    return true
end

opts.sources = {
    { name = "nvim_lsp" },
    { name = "path" },
    { name = "buffer" },
}

opts.completion = {
    completeopt = vim.o.completeopt,
}

local function has_words_before()
    local cursor = vim.api.nvim_win_get_cursor(0)
    local line, col = cursor[1], cursor[2]
    return col ~= 0
        and vim.api.nvim_buf_get_lines(0, line - 1, line, true)[1]:sub(col, col):match("%s")
            == nil
end

local mapping = cmp.mapping

opts.mapping = mapping.preset.insert({
    ["<Tab>"] = mapping(function(fallback)
        if cmp.visible() then
            cmp.select_next_item()
        elseif vim.snippet.active({ direction = 1 }) then
            vim.snippet.jump(1)
        elseif vim.lsp.inline_completion.get() then
            return
        elseif has_words_before() then
            cmp.complete()
        else
            fallback()
        end
    end, { "i", "c", "s" }),
    ["<S-Tab>"] = mapping(function(fallback)
        if cmp.visible() then
            cmp.select_prev_item()
        elseif vim.snippet.active({ direction = -1 }) then
            vim.snippet.jump(-1)
        else
            fallback()
        end
    end, { "i", "c", "s" }),
    ["<CR>"] = mapping.confirm({ select = true }),
    ["<C-e>"] = mapping.abort(),
    ["<C-d>"] = mapping.scroll_docs(-4),
    ["<C-f>"] = mapping.scroll_docs(4),
})

opts.snippet = {
    expand = function(args)
        vim.snippet.expand(args.body)
    end,
}

opts.window = {
    completion = {
        winhighlight = "Normal:Pmenu,CursorLine:PmenuSel,FloatBorder:FloatBorder,Search:None",
        col_offset = -3,
        side_padding = 0,
        scrollbar = true,
        scrolloff = 8,
        winblend = 11,
    },
    documentation = {
        winhighlight = "Normal:Pmenu,FloatBorder:FloatBorder,Search:None",
        winblend = 11,
    },
}

opts.formatting = {
    fields = { "kind", "abbr", "menu" },
    ---@type fun(entry, vim_item): any
    format = function(_, vim_item)
        vim_item.kind = " " .. ui.kind[vim_item.kind] .. "⠀"
        vim_item.abbr = ui.truncate(vim_item.abbr:gsub(vim.pesc("..."), ui.ellipsis), 50)
        do
            local menu = vim_item.menu or ""
            if vim.bo.filetype == "rust" then
                menu = menu:gsub("%(use ([^%)]+)%)%s*(.*)", "%2 (%1)")
                    :gsub("%(alias ([^%)]+)%)%s*(.*)", "%2 (alias %1)")
                    :gsub("%(as [^%)]+%)", "")
                    :gsub("unsafe ", "")
                    :gsub("const ", "")
            end
            vim_item.menu = ui.truncate(vim.fn.trim(menu), 70)
        end
        return vim_item
    end,
}

cmp.setup(opts)

cmp.setup.cmdline(":", {
    mapping = cmp.mapping.preset.cmdline(),
    sources = cmp.config.sources({
        { name = "path" },
    }, {
        { name = "cmdline" },
    }),
})

cmp.setup.cmdline({ "/", "?" }, {
    mapping = cmp.mapping.preset.cmdline(),
    sources = {
        { name = "buffer" },
    },
})

-- if border ~= 'none' then
--   local thumb = {}
--   for _ = 1, vim.o.lines do
--     table.insert(thumb, '┃')
--   end
--   require('cmp.utils.buffer').cache = setmetatable({}, {
--     ---@param name string|integer
--     ---@param buf buffer
--     __newindex = function(t, name, buf)
--       if type(name) == 'string' and name:find('thumb_buf') then
--         vim.api.nvim_buf_set_lines(buf, 0, 1, false, thumb)
--       end
--       rawset(t, name, buf)
--     end,
--   })
-- end