-- Nvim LSP Config

local map_opts = { noremap=true, silent=true }

vim.keymap.set('n', '<space>e', vim.diagnostic.open_float, map_opts)
vim.keymap.set('n', '<space>p', vim.diagnostic.goto_prev, map_opts)
vim.keymap.set('n', '<space>n', vim.diagnostic.goto_next, map_opts)
vim.keymap.set('n', '<space>l', vim.diagnostic.setloclist, map_opts)


-- Enable keybinds on LSP server attach
local on_attach = function(client, bufnr)
    -- Enable completion triggered by <C-x><C-o>
    vim.api.nvim_buf_set_option(bufnr, 'omnifunc', 'v:lua.vim.lsp.omnifunc')

    -- Mappings
    local bufopts = { noremap=true, silent=true, buffer=bufnr }
    vim.keymap.set('n', 'gD', vim.lsp.buf.declaration, bufopts)
    vim.keymap.set('n', 'gd', vim.lsp.buf.definition, bufopts)
    vim.keymap.set('n', 'K', vim.lsp.buf.hover, bufopts)
    vim.keymap.set('n', 'gi', vim.lsp.buf.implementation, bufopts)
    vim.keymap.set('n', '<C-k>', vim.lsp.buf.signature_help, bufopts)
    vim.keymap.set('n', '<space>wa', vim.lsp.buf.add_workspace_folder, bufopts)
    vim.keymap.set('n', '<space>wr', vim.lsp.buf.remove_workspace_folder, bufopts)
    vim.keymap.set('n', '<space>wl', function()
        print(vim.inspect(vim.lsp.buf.list_workspace_folders()))
    end, bufopts)
    vim.keymap.set('n', '<space>D', vim.lsp.buf.type_definition, bufopts)
    vim.keymap.set('n', '<space>rn', vim.lsp.buf.rename, bufopts)
    vim.keymap.set('n', '<space>ca', vim.lsp.buf.code_action, bufopts)
    vim.keymap.set('n', 'gr', vim.lsp.buf.references, bufopts)
    vim.keymap.set('n', '<space>f', function() vim.lsp.buf.format { async = true } end, bufopts)
end

-- Set-up autocompletion

local cmp = require('cmp')
vim.opt.completeopt = {'menu', 'menuone', 'noselect'}

cmp.setup({
    snippet = {
        -- Necessary snippet engine
        expand = function (args)
            vim.fn["vsnip#anonymous"](args.body)
        end,
    },

    window = {
        -- completion = cmp.config.window.bordered(),
        -- documentation = cmp.config.window.bordered,
    },

    mapping = cmp.mapping.preset.insert({
        ['<C-u>'] = cmp.mapping.scroll_docs(4),
        ['<C-d>'] = cmp.mapping.scroll_docs(-4),
        ['<C-Space>'] = cmp.mapping.complete(),
        ['<C-e>'] = cmp.mapping.abort(),
        ['<CR>'] = cmp.mapping.confirm({select = true}),
    }),

    sources = cmp.config.sources({
        { name = 'nvim_lsp' },
        { name = 'vsnip' },
    }, { { name = 'buffer' } }),
})


-- Language servers setup
local capabilities = require('cmp_nvim_lsp').default_capabilities()

require('lspconfig')['rust_analyzer'].setup {
    on_attach = on_attach,
    capabilities = capabilities,
}

require('lspconfig')['rnix'].setup {
    on_attach = on_attach,
    capabilities = capabilities
}

require('lspconfig')["nil_ls"].setup {
    on_attach = on_attach,
    capabilities = capabilities
}

require('lspconfig')['ltex'].setup {
    on_attach = on_attach,
    capabilities = capabilities
}

require('lspconfig')['texlab'].setup {
    on_attach = on_attach,
    capabilities = capabilities
}