use {'kevinhwang91/nvim-ufo', requires = 'kevinhwang91/promise-async'}

use {'kevinhwang91/nvim-ufo', requires = 'kevinhwang91/promise-async'}

vim.o.foldcolumn = '1' -- '0' is not bad
vim.o.foldlevel = 99 -- Using ufo provider need a large value, feel free to decrease the value
vim.o.foldlevelstart = 99
vim.o.foldenable = true

-- Using ufo provider need remap `zR` and `zM`. If Neovim is 0.6.1, remap yourself
vim.keymap.set('n', 'zR', require('ufo').openAllFolds)
vim.keymap.set('n', 'zM', require('ufo').closeAllFolds)

-- Option 1: coc.nvim as LSP client
use {'neoclide/coc.nvim', branch = 'master', run = 'yarn install --frozen-lockfile'}
require('ufo').setup()
--

-- Option 2: nvim lsp as LSP client
-- Tell the server the capability of foldingRange,
-- Neovim hasn't added foldingRange to default capabilities, users must add it manually
local capabilities = vim.lsp.protocol.make_client_capabilities()
capabilities.textDocument.foldingRange = {
    dynamicRegistration = false,
    lineFoldingOnly = true
}
local language_servers = require("lspconfig").util.available_servers() -- or list servers manually like {'gopls', 'clangd'}
for _, ls in ipairs(language_servers) do
    require('lspconfig')[ls].setup({
        capabilities = capabilities
        -- you can add other fields for setting up lsp server in this table
    })
end
require('ufo').setup()
--

-- Option 3: treesitter as a main provider instead
-- Only depend on `nvim-treesitter/queries/filetype/folds.scm`,
-- performance and stability are better than `foldmethod=nvim_treesitter#foldexpr()`
use {'nvim-treesitter/nvim-treesitter', run = ':TSUpdate'}
require('ufo').setup({
    provider_selector = function(bufnr, filetype, buftype)
        return {'treesitter', 'indent'}
    end
})
--

-- Option 4: disable all providers for all buffers
-- Not recommend, AFAIK, the ufo's providers are the best performance in Neovim
require('ufo').setup({
    provider_selector = function(bufnr, filetype, buftype)
        return ''
    end
})

{
    open_fold_hl_timeout = {
        description = [[Time in millisecond between the range to be highlgihted and to be cleared
                    while opening the folded line, `0` value will disable the highlight]],
        default = 400
    },
    provider_selector = {
        description = [[A function as a selector for fold providers. For now, there are
                    'lsp' and 'treesitter' as main provider, 'indent' as fallback provider]],
        default = nil
    },
    close_fold_kinds = {
        description = [[After the buffer is displayed (opened for the first time), close the
                    folds whose range with `kind` field is included in this option. For now,
                    'lsp' provider's standardized kinds are 'comment', 'imports' and 'region',
                    run `UfoInspect` for details if your provider has extended the kinds.]],
        default = {}
    },
    fold_virt_text_handler = {
        description = [[A function customize fold virt text, see ### Customize fold text]],
        default = nil
    },
    enable_get_fold_virt_text = {
        description = [[Enable a function with `lnum` as a parameter to capture the virtual text
                    for the folded lines and export the function to `get_fold_virt_text` field of
                    ctx table as 6th parameter in `fold_virt_text_handler`]],
        default = false
    },
    preview = {
        description = [[Configure the options for preview window and remap the keys for current
                    buffer and preview buffer if the preview window is displayed.
                    Never worry about the users's keymaps are overridden by ufo, ufo will save
                    them and restore them if preview window is closed.]],
        win_config = {
            border = {
                description = [[The border for preview window,
                    `:h nvim_open_win() | call search('border:')`]],
                default = 'rounded',
            },
            winblend = {
                description = [[The winblend for preview window, `:h winblend`]],
                default = 12,
            },
            winhighlight = {
                description = [[The winhighlight for preview window, `:h winhighlight`]],
                default = 'Normal:Normal',
            },
            maxheight = {
                description = [[The max height of preview window]],
                default = 20,
            }
        },
        mappings = {
            description = [[The table for {function = key}]],
            default = [[see ###Preview function table for detail]],
        }
    }
}

local ftMap = {
    vim = 'indent',
    python = {'indent'},
    git = ''
}
require('ufo').setup({
    open_fold_hl_timeout = 150,
    close_fold_kinds = {'imports', 'comment'},
    preview = {
        win_config = {
            border = {'', '─', '', '', '', '─', '', ''},
            winhighlight = 'Normal:Folded',
            winblend = 0
        },
        mappings = {
            scrollU = '<C-u>',
            scrollD = '<C-d>',
            jumpTop = '[',
            jumpBot = ']'
        }
    },
    provider_selector = function(bufnr, filetype, buftype)
        -- if you prefer treesitter provider rather than lsp,
        -- return ftMap[filetype] or {'treesitter', 'indent'}
        return ftMap[filetype]

        -- refer to ./doc/example.lua for detail
    end
})
vim.keymap.set('n', 'zR', require('ufo').openAllFolds)
vim.keymap.set('n', 'zM', require('ufo').closeAllFolds)
vim.keymap.set('n', 'zr', require('ufo').openFoldsExceptKinds)
vim.keymap.set('n', 'zm', require('ufo').closeFoldsWith) -- closeAllFolds == closeFoldsWith(0)
vim.keymap.set('n', 'K', function()
    local winid = require('ufo').peekFoldedLinesUnderCursor()
    if not winid then
        -- choose one of coc.nvim and nvim lsp
        vim.fn.CocActionAsync('definitionHover') -- coc.nvim
        vim.lsp.buf.hover()
    end
end)

local handler = function(virtText, lnum, endLnum, width, truncate)
    local newVirtText = {}
    local suffix = (' 󰁂 %d '):format(endLnum - lnum)
    local sufWidth = vim.fn.strdisplaywidth(suffix)
    local targetWidth = width - sufWidth
    local curWidth = 0
    for _, chunk in ipairs(virtText) do
        local chunkText = chunk[1]
        local chunkWidth = vim.fn.strdisplaywidth(chunkText)
        if targetWidth > curWidth + chunkWidth then
            table.insert(newVirtText, chunk)
        else
            chunkText = truncate(chunkText, targetWidth - curWidth)
            local hlGroup = chunk[2]
            table.insert(newVirtText, {chunkText, hlGroup})
            chunkWidth = vim.fn.strdisplaywidth(chunkText)
            -- str width returned from truncate() may less than 2nd argument, need padding
            if curWidth + chunkWidth < targetWidth then
                suffix = suffix .. (' '):rep(targetWidth - curWidth - chunkWidth)
            end
            break
        end
        curWidth = curWidth + chunkWidth
    end
    table.insert(newVirtText, {suffix, 'MoreMsg'})
    return newVirtText
end

-- global handler
-- `handler` is the 2nd parameter of `setFoldVirtTextHandler`,
-- check out `./lua/ufo.lua` and search `setFoldVirtTextHandler` for detail.
require('ufo').setup({
    fold_virt_text_handler = handler
})

-- buffer scope handler
-- will override global handler if it is existed
-- local bufnr = vim.api.nvim_get_current_buf()
-- require('ufo').setFoldVirtTextHandler(bufnr, handler)