import Application from require "lapis"
import json_params, capture_errors_json, yield_error from require "lapis.application"
import assert_valid from require "lapis.validate"

import APIKeys, Users, Tasks from require "models"
-- import locate from require "locator"
-- import random from locate "calc"
-- import escape_similar_to from locate "db"

class API extends Application
  @path: "/v1"
  @name: "api_"

  @before_filter( capture_errors_json json_params =>
    -- TODO implement Authorization: api_key VALUE as acceptable method to send api_key
    yield_error "api_key not specified!" unless @params.api_key
    @api_key = APIKeys\find key: @params.api_key
    yield_error "Invalid api_key" unless @api_key
    @user = Users\find id: @api_key.user_id
    yield_error "Invalid api_key!" unless @user -- NOTE this should also delete the api_key and error (this should never happen!)
  )

  -- TODO intentionally cause an error to see if this is working as intended
  handle_error: (err, trace) =>
    return status: 500, json: { errors: {err}, :trace } -- NOTE trace should be saved and NOT returned to the user

  [err_test: "/err"]: =>
    error "this is a testing error"

  [new: "/new"]: capture_errors_json json_params =>
    assert_valid @params, {
      {"content", exists: true, min_length: 1, "Task content not specified."}
    }

    task, err = Tasks\create {
      user_id: @user.id
      content: @params.content
    }
    yield_error err unless task

    return json: { success: true, :task }

  [do: "/do"]: capture_errors_json json_params =>
    local task
    if @params.id
      assert_valid @params, {
        {"id", exists: true, min_length: 1, "Attempted to select by task id, but no id specified."}
        {"id", is_integer: true, "Task id is not an integer."}
      }
      task = Tasks\find id: @params.id, user_id: @user.id
    elseif @params.content
      assert_valid @params, {
        {"content", exists: true, min_length: 1, "Attempted to select by task content, but no content specified."}
      }
      task = Tasks\find content: @params.content, user_id: @user.id
    else
      yield_error "Task id or content not specified."

    yield_error "Invalid task specified." unless task
    task, err = task\update done: true
    yield_error err unless task

    return json: { success: true, :task }

  [undo: "/undo"]: capture_errors_json json_params =>
    local task
    if @params.id
      assert_valid @params, {
        {"id", exists: true, min_length: 1, "Attempted to select by task id, but no id specified."}
        {"id", is_integer: true, "Task id is not an integer."}
      }
      task = Tasks\find id: @params.id, user_id: @user.id
    elseif @params.content
      assert_valid @params, {
        {"content", exists: true, min_length: 1, "Attempted to select by task content, but no content specified."}
      }
      task = Tasks\find content: @params.content, user_id: @user.id
    else
      yield_error "Task id or content not specified."

    yield_error "Invalid task specified." unless task
    task, err = task\update done: false
    yield_error err unless task

    return json: { success: true, :task }

  [random: "/random"]: capture_errors_json json_params =>
    assert_valid @params, {
      {"count", exists: true, is_integer: true, optional: true, "Count is not an integer."}
      {"done", exists: true, one_of: {true, false}, optional: true, "Done is not a boolean."}
    }
    @params.count or= 1
    @params.done = false if @params.done == nil

    -- TODO figure out how to return random selection
    -- possibly need to store how many items each user has and use a different strategy for users with low amounts vs high amounts
    -- key = get_key(@)
    --
    -- local tasks
    -- if @params.done
    --   offset = random Tasks\count "user_id = ? AND done = ? ORDER BY id ASC", key.user_id, @params.done
    --   tasks = Tasks\select "WHERE user_id = ? AND done = ? ORDER BY id ASC OFFSET ? LIMIT 1", key.user_id, @params.done, offset
    -- else
    --   offset = random Tasks\count "user_id = ? ORDER BY id ASC", key.user_id
    --   tasks = Tasks\select "WHERE user_id = ? ORDER BY id ASC OFFSET ? LIMIT 1", key.user_id, offset
    --
    -- if tasks and #tasks == 1
    --   return json: { success: true, task: tasks[1] }
    -- else
    --   return standard_err!
    return status: 501, json: { errors: {"Not implemented."} }

  [list: "/list"]: capture_errors_json json_params =>
    assert_valid @params, {
      {"count", exists: true, is_integer: true, optional: true, "Count is not an integer."}
      {"done", exists: true, one_of: {true, false}, optional: true, "Done is not a boolean."}
      {"page", exists: true, is_integer: true, optional: true, "Page is not an integer."}
      {"order", exists: true, one_of: {"asc", "desc"}, optional: true, "Invalid order. (Must be 'asc' or 'desc'.)"}
    }
    @params.count or= 50
    @params.page or= 1
    @params.order or= "asc" -- may need to be "desc", don't remember o.o
    yield_error "Invalid page. (Must be a positive integer.)" if @params.page < 1

    local Paginator
    if @params.done == nil
      Paginator = Tasks\paginated "WHERE user_id = ? ORDER BY created_at ?", @user.id, @params.order, per_page: @params.count
    else
      Paginator = Tasks\paginated "WHERE user_id = ? AND done = ? ORDER BY created_at ?", @user.id, @params.done, @params.order, per_page: @params.count

    num_pages = Paginator\num_pages!
    if num_pages < @params.page
      @params.page = num_pages
    tasks = Paginator\get_page(@params.page)

    -- returns page in case it returned a different page than you asked for! (in the case you ask for a page beyond the end)
    return json: { success: true, page: @params.page, :tasks }

  -- /new { content: "string" }
  -- /do { id: # } or content
  -- /undo { id: # } or content
  -- /get { id: # } or content
  -- /random { count: #, done: bool } (both args optional, defaults count 1, done false)
  -- /list { count: #, done: bool, page: #, order: asc/desc } (if done not specified, returns all,
  --                        default count is 50, default page is 1, default order is latest first
  --
  -- Add ability to send out subscription webhooks.