--
-- lsp-ext.lua


M = {}

function M.preview_location(location, context, before_context)
    -- location may be LocationLink or Location (more useful for the former)
    context = context or 15
    before_context = before_context or 0
    local uri = location.targetUri or location.uri
    if uri == nil then
        return
    end
    local bufnr = vim.uri_to_bufnr(uri)
    if not vim.api.nvim_buf_is_loaded(bufnr) then
        vim.fn.bufload(bufnr)
    end
    local range = location.targetRange or location.range
    local contents =
        vim.api.nvim_buf_get_lines(bufnr, range.start.line - before_context, range["end"].line + 1 + context, false)
    local filetype = vim.api.nvim_buf_get_option(bufnr, "filetype")
    return vim.lsp.util.open_floating_preview(contents, filetype)
end

function M.preview_location_callback(_, method, result)
    local context = 15
    if result == nil or vim.tbl_isempty(result) then
        print("No location found: " .. method)
        return nil
    end
    if vim.tbl_islist(result) then
        M.floating_buf, M.floating_win = M.preview_location(result[1], context)
    else
        M.floating_buf, M.floating_win = M.preview_location(result, context)
    end
end

function M.peek_definition()
    if vim.tbl_contains(vim.api.nvim_list_wins(), M.floating_win) then
        vim.api.nvim_set_current_win(M.floating_win)
    else
        local params = vim.lsp.util.make_position_params()
        return vim.lsp.buf_request(0, "textDocument/definition", params, M.preview_location_callback)
    end
end

return M