-- this is a helper/orchestrator for apicalls/syncs
--
-- implemented in openbrush.lua

local apiSync = {
  
  init = function(pluginname)
    local plugin = app.plugin[pluginname]
    local api    = {}
    api.pluginname = pluginname
    if not plugin.apiCall or not plugin.fetch or not plugin.download then 
      print("apiSync.lua: plugin " .. pluginname .. " does not implement the apiSync interface")
      os.exit()
    end
    api.apiCall      = plugin.apiCall
    api.fetch        = plugin.fetch
    api.download     = plugin.download

    api.syncHashtags = function(opts)
      local synced = 0
      local tags   = opts.tags
      if #tags == 0 then table.insert(tags,'') end
      foreach( tags, function(k,tag)
        local url = opts.apiCall( #tag > 0 and tag or nil)
        opts.body = nil -- erase previous url result
        print('🤞 fetch ' .. url)
        local t = opts.fetch(url,opts)
        if t then 
          synced = synced + opts.download(t,tag)
        end
      end, true)
      if synced > 0 then 
        app.cache.url = {} -- delete page cache
        app.plugin.diskscan.scan(app.opts.plugin_diskscan_dir)
      end
      return synced
    end

    api.sync       = function(api)
      if #app.opts['plugin_' .. pluginname .. '_sync_URL'] > 0 and util.cmdExist('wget') then 
        local synced = api.syncHashtags({
          tags     = util.split( app.opts['plugin_' .. api.pluginname .. '_sync_hashtag'] or '', ' '),
          apiCall  = api.apiCall,
          fetch    = api.fetch,
          download = api.download
        })
      end
    end

    -- runs sync in foreground
    app.on('reset', function()
      api.sync(api) 
    end)

    -- runs sync in foreground
    app.on('init', function()
      if util.contains(argv, 'generate') then api.sync(api) end
    end)

    -- runs sync background
    app.on('scheduler', function(opts)
      if util.contains(argv, 'server') then
        if opts.interval == app.opts['plugin_' .. pluginname .. '_sync_when'] then 
          api.sync(api)
        end
      end
    end)
    return api
  end

}

return apiSync