-- see `:help` for any questions
-- use `&<var>` to show value of vimscript variable


-- API --
-- o     = vim.o     -- options
-- go    = vim.go    -- only-global options
-- bo    = vim.bo    -- buffer local options
-- wo    = vim.wo    -- window local options

-- cmd   = vim.cmd   -- vim commands
-- fn    = vim.fn    -- vim functions
-- opt   = vim.opt   -- vim option object

-- g     = vim.g     -- global variables
-- b     = vim.b     -- buffer local variables
-- w     = vim.w     -- window local variables
-- t     = vim.t     -- tab local variables
-- v     = vim.v     -- variables
-- env   = vim.env   -- environment variables

-- dependent on https://github.com/hrsh7th/nvim-compe

require'compe'.setup {
    enabled = true;
    autocomplete = true;
    debug = false;
    min_length = 1;
    preselect = 'enable';
    throttle_time = 80;
    source_timeout = 200;
    incomplete_delay = 400;
    max_abbr_width = 100;
    max_kind_width = 100;
    max_menu_width = 100;
    documentation = false;

    source = {
        path = true;
        buffer = true;
        calc = true;
        vsnip = true;
        nvim_lsp = true;
        nvim_lua = true;
        spell = true;
        tags = true;
        snippets_nvim = true;
        treesitter = true;
    };
}
local t = function(str)
    return vim.api.nvim_replace_termcodes(str, true, true, true)
end

local check_back_space = function()
    local col = fn.col('.') - 1
    if col == 0 or fn.getline('.'):sub(col, col):match('%s') then
        return true
    else
        return false
    end
end

-- Use (s-)tab to:
--- move to prev/next item in completion menuone
--- jump to prev/next snippet's placeholder
_G.tab_complete = function()
    if fn.pumvisible() == 1 then
        return t "<C-n>"
    elseif fn.call("vsnip#available", {1}) == 1 then
        return t "<Plug>(vsnip-expand-or-jump)"
    elseif check_back_space() then
        return t "<Tab>"
    else
        return fn['compe#complete']()
    end
end
_G.s_tab_complete = function()
    if fn.pumvisible() == 1 then
        return t "<C-p>"
    elseif fn.call("vsnip#jumpable", {-1}) == 1 then
        return t "<Plug>(vsnip-jump-prev)"
    else
      -- If <S-Tab> is not working in your terminal, change it to <C-h>
        return t "<S-Tab>"
    end
end

map("i", "<Tab>", "v:lua.tab_complete()", {expr = true})
map("s", "<Tab>", "v:lua.tab_complete()", {expr = true})
map("i", "<S-Tab>", "v:lua.s_tab_complete()", {expr = true})
map("s", "<S-Tab>", "v:lua.s_tab_complete()", {expr = true})

map('i', '<cr>', 'compe#confirm("<cr>")', { expr = true })
map('i', '<c-space>', 'compe#complete()', { expr = true })