local M = {}

function M.cmp_conf()
    local cmp = require('cmp')
    local luasnip = require('luasnip')

    local check_back_space = function()
        local col = vim.fn.col '.' - 1
        return col == 0 or vim.fn.getline('.'):sub(col, col):match '%s' ~= nil
    end

    local t = function(str)
        return vim.api.nvim_replace_termcodes(str, true, true, true)
    end

    cmp.setup {
        formatting = {
            format = function(entry, vim_item)
                local lspkind_icons = {
                    Text = '',
                    Method = '',
                    Function = '',
                    Constructor = '',
                    Field = 'ﰠ',
                    Variable = '',
                    Class = 'ﴯ',
                    Interface = '',
                    Module = '',
                    Property = 'ﰠ',
                    Unit = '塞',
                    Value = '',
                    Enum = '',
                    Keyword = '',
                    Snippet = '',
                    Color = '',
                    File = '',
                    Reference = '',
                    Folder = '',
                    EnumMember = '',
                    Constant = '',
                    Struct = 'פּ',
                    Event = '',
                    Operator = '',
                    TypeParameter = ''
                }
                -- load lspkind icons
                vim_item.kind = string.format('%s %s', lspkind_icons[vim_item.kind], vim_item.kind)

                vim_item.menu = ({
                    luasnip = '[SNIP]',
                    path = '[PATH]',
                    buffer = '[BUF]',
                    -- calc = '[CALC]',
                    -- nuspell = '[SPELL]',
                    spell = '[SPELL]',
                    emoji = '[EMOJI]',
                    nvim_lsp = '[LSP]',
                    latex_symbols = '[TEX]',
                    tmux = '[TMUX]',
                    orgmode = '[ORG]'
                })[entry.source.name]

                return vim_item
            end
        },
        mapping = {
            ['<C-Space>'] = cmp.mapping.complete(),
            ['<C-p>'] = cmp.mapping.select_prev_item(),
            ['<C-n>'] = cmp.mapping.select_next_item(),
            ['<C-d>'] = cmp.mapping.scroll_docs(-4),
            ['<C-f>'] = cmp.mapping.scroll_docs(4),
            ['<C-e>'] = cmp.mapping.close(),
            -- supertab-like mapping
            ['<Tab>'] = cmp.mapping(function(fallback)
                if vim.fn.pumvisible() == 1 then
                    vim.fn.feedkeys(t('<C-n>'), 'n')
                elseif luasnip.expand_or_jumpable() then
                    vim.fn.feedkeys(t('<Plug>luasnip-expand-or-jump'), '')
                elseif check_back_space() then
                    vim.fn.feedkeys(t('<Tab>'), 'n')
                else
                    fallback()
                end
            end, {'i', 's'}),
            ['<S-Tab>'] = cmp.mapping(function(fallback)
                if vim.fn.pumvisible() == 1 then
                    vim.fn.feedkeys(t('<C-p>'), 'n')
                elseif luasnip.jumpable(-1) then
                    vim.fn.feedkeys(t('<Plug>luasnip-jump-prev'), '')
                else
                    fallback()
                end
            end, {'i', 's'})
        },
        snippet = {
            expand = function(args)
                luasnip.lsp_expand(args.body)
            end
        },
        sources = {
            {name = 'luasnip'},
            {name = 'path'},
            {name = 'buffer'},
            -- {name = 'calc'},
            -- {name = 'nuspell'},
            {name = 'spell'},
            {name = 'emoji'},
            {name = 'nvim_lsp'},
            {name = 'latex_symbols'},
            {name = 'tmux'},
            {name = 'orgmode'}
        }
    }
end

function M.autopairs_conf()
    require('nvim-autopairs').setup {fast_wrap = {}}
    require('nvim-autopairs.completion.cmp').setup({
        map_cr = true, --  map <CR> on insert mode
        map_complete = true, -- it will auto insert `(` after select function or method item
        auto_select = true -- automatically select the first item
    })
end

function M.snippets_conf()
    require('luasnip').config.set_config({
        updateevents = 'TextChanged, TextChangedI',
        history = true
    })

    -- Loading vscode-like snippets from 'friendly-snippets'
    require('luasnip/loaders/from_vscode').load()
end

function M.coq_conf()
    -- To add snippets from lsp servers, change lsp.lua:
    -----
    -- local coq = require('coq')
    -- lspconf.<server>.setup(...) --> lspconf.<server>.setup(coq.lsp_ensure_capabilities(...))
    vim.g.coq_settings = {
        auto_start = true,
        display = {
            icons = {
                mode = 'none'
            }
        }
    }
end

function M.autotag_conf()
    require('nvim-treesitter.configs').setup {
        autotag = {enable = true}
    }
end

return M