feat: Add getCronFromFrequency to manifest models

This feature is imported from harvest and allows to get the cron string
from a given frequency like 'daily'.

This cron string will configure the trigger associated to the konnector

docs/api/cozy-client/interfaces/manifest.FrequencyOptions.md

@@ -0,0 +1,55 @@
+[cozy-client](../README.md) / [manifest](../modules/manifest.md) / FrequencyOptions
+
+# Interface: FrequencyOptions<>
+
+[manifest](../modules/manifest.md).FrequencyOptions
+
+frequency options object
+
+## Properties
+
+### dayOfMonth
+
+• **dayOfMonth**: `number`
+
+day of the month
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:329](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L329)
+
+***
+
+### dayOfWeek
+
+• **dayOfWeek**: `number`
+
+day of the week
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:330](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L330)
+
+***
+
+### hours
+
+• **hours**: `number`
+
+hours
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:331](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L331)
+
+***
+
+### minutes
+
+• **minutes**: `number`
+
+minutes
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:332](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L332)

docs/api/cozy-client/interfaces/manifest.randomDayTimeResult.md

@@ -0,0 +1,29 @@
+[cozy-client](../README.md) / [manifest](../modules/manifest.md) / randomDayTimeResult
+
+# Interface: randomDayTimeResult<>
+
+[manifest](../modules/manifest.md).randomDayTimeResult
+
+## Properties
+
+### hours
+
+• **hours**: `number`
+
+hours
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:323](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L323)
+
+***
+
+### minutes
+
+• **minutes**: `number`
+
+minutes
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:324](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L324)

docs/api/cozy-client/modules/manifest.md

@@ -2,6 +2,11 @@
 
 # Namespace: manifest
 
+## Interfaces
+
+*   [FrequencyOptions](../interfaces/manifest.FrequencyOptions.md)
+*   [randomDayTimeResult](../interfaces/manifest.randomDayTimeResult.md)
+
 ## Variables
 
 ### ROLE_IDENTIFIER
@@ -22,7 +27,7 @@ Legacy login fields declared by some konnectors
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:11](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L11)
+[packages/cozy-client/src/models/manifest.js:21](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L21)
 
 ## Functions
 
@@ -42,7 +47,59 @@ Legacy login fields declared by some konnectors
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:63](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L63)
+[packages/cozy-client/src/models/manifest.js:73](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L73)
+
+***
+
+### getCronFromFrequency
+
+▸ **getCronFromFrequency**(`frequency`, `options?`): `string`
+
+Build a cron string for given frequency with given options
+See https://docs.cozy.io/en/cozy-stack/jobs/#cron-syntax
+
+*Parameters*
+
+| Name | Type | Description |
+| :------ | :------ | :------ |
+| `frequency` | `"hourly"` | `"daily"` | `"weekly"` | `"monthly"` | Frequency |
+| `options` | [`FrequencyOptions`](../interfaces/manifest.FrequencyOptions.md) | - |
+
+*Returns*
+
+`string`
+
+*   The cron definition for trigger
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:280](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L280)
+
+***
+
+### getCronFromKonnector
+
+▸ **getCronFromKonnector**(`konnector`, `startDate?`, `randomDayTimeFn?`): `string`
+
+Build a cron string for given konnector and from a given start date
+
+*Parameters*
+
+| Name | Type | Default value | Description |
+| :------ | :------ | :------ | :------ |
+| `konnector` | `IOCozyKonnector` | `undefined` | io.cozy.konnectors object |
+| `startDate` | `Date` | `undefined` | start date |
+| `randomDayTimeFn` | `Function` | `randomDayTime` | - |
+
+*Returns*
+
+`string`
+
+*   The cron definition for trigger
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:307](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L307)
 
 ***
 
@@ -66,7 +123,7 @@ The key for the identifier field, example 'login'
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:161](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L161)
+[packages/cozy-client/src/models/manifest.js:171](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L171)
 
 ***
 
@@ -86,7 +143,33 @@ The key for the identifier field, example 'login'
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:67](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L67)
+[packages/cozy-client/src/models/manifest.js:77](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L77)
+
+***
+
+### randomDayTime
+
+▸ **randomDayTime**(`start?`, `end?`, `randomize?`): [`randomDayTimeResult`](../interfaces/manifest.randomDayTimeResult.md)
+
+Returns an hour of the day between two hours given in parameters
+
+*Parameters*
+
+| Name | Type | Default value | Description |
+| :------ | :------ | :------ | :------ |
+| `start` | `number` | `0` | minimal start hour |
+| `end` | `number` | `1` | maximal end hour |
+| `randomize` | `Function` | `undefined` | The function used to generate random values |
+
+*Returns*
+
+[`randomDayTimeResult`](../interfaces/manifest.randomDayTimeResult.md)
+
+Object containing two atributes : hours and minutes
+
+*Defined in*
+
+[packages/cozy-client/src/models/manifest.js:248](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L248)
 
 ***
 
@@ -108,7 +191,7 @@ Normalize app manifest, retro-compatibility for old manifests
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:77](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L77)
+[packages/cozy-client/src/models/manifest.js:87](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L87)
 
 ***
 
@@ -132,7 +215,7 @@ sanitized categories
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:56](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L56)
+[packages/cozy-client/src/models/manifest.js:66](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L66)
 
 ***
 
@@ -156,4 +239,4 @@ Ensures that fields has at least one field with the role 'identifier'
 
 *Defined in*
 
-[packages/cozy-client/src/models/manifest.js:130](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L130)
+[packages/cozy-client/src/models/manifest.js:140](https://github.com/cozy/cozy-client/blob/master/packages/cozy-client/src/models/manifest.js#L140)

packages/cozy-client/src/models/manifest.js

@@ -5,6 +5,16 @@ import findKey from 'lodash/findKey'
 
 export const ROLE_IDENTIFIER = 'identifier'
 
+const DAILY = 'daily'
+const HOURLY = 'hourly'
+const WEEKLY = 'weekly'
+const MONTHLY = 'monthly'
+const VALID_FREQUENCIES = [DAILY, HOURLY, WEEKLY, MONTHLY]
+
+const DEFAULT_FREQUENCY = WEEKLY
+// By default konnectors are run at random hour between 12:00PM and 05:00AM.
+const DEFAULT_TIME_INTERVAL = [0, 5]
+
 /**
  * Legacy login fields declared by some konnectors
  */
@@ -226,3 +236,98 @@ const sanitizeFields = _flow([
   sanitizeRequired,
   sanitizeEncrypted
 ])
+
+/**
+ * Returns an hour of the day between two hours given in parameters
+ *
+ * @param {number} start minimal start hour
+ * @param {number} end maximal end hour
+ * @param {function} randomize The function used to generate random values
+ * @returns {randomDayTimeResult} Object containing two atributes : hours and minutes
+ */
+export const randomDayTime = (
+  start = 0,
+  end = 1,
+  randomize = (min, max) => Math.random() * (max - min) + min
+) => {
+  if (typeof start !== 'number')
+    throw new Error('Parameter start must be a number')
+  if (typeof end !== 'number') throw new Error('Parameter end must be a number')
+
+  if (typeof randomize !== 'function')
+    throw new Error('Parameter randomize must be a function')
+
+  if (start < 0 || end > 24) throw new Error('interval must be inside [0, 24]')
+
+  const r = randomize(start, end)
+  const hours = Math.floor(r)
+  const minutes = Math.floor((r - hours) * 60)
+
+  if (hours < 0 || hours > 23)
+    throw new Error('randomize function returns invalid hour value')
+
+  return { hours, minutes }
+}
+
+/**
+ * Build a cron string for given frequency with given options
+ * See https://docs.cozy.io/en/cozy-stack/jobs/#cron-syntax
+ *
+ * @param  {'hourly'|'daily'|'weekly'|'monthly'} frequency Frequency
+ * @param  {FrequencyOptions} [options] - FrequencyOptions object
+ * @returns {String} - The cron definition for trigger
+ */
+export const getCronFromFrequency = (frequency, options = {}) => {
+  const { dayOfMonth = 1, dayOfWeek = 1, hours = 0, minutes = 0 } = options
+  const sanitizedFrequency = VALID_FREQUENCIES.includes(frequency)
+    ? frequency
+    : DEFAULT_FREQUENCY
+
+  switch (sanitizedFrequency) {
+    case DAILY:
+      return `0 ${minutes} ${hours} * * *`
+    case HOURLY:
+      return `0 ${minutes} * * * *`
+    case MONTHLY:
+      return `0 ${minutes} ${hours} ${dayOfMonth} * *`
+    default:
+      // also WEEKLY
+      return `0 ${minutes} ${hours} * * ${dayOfWeek}`
+  }
+}
+
+/**
+ * Build a cron string for given konnector and from a given start date
+ *
+ * @param {import('../types').IOCozyKonnector} konnector - io.cozy.konnectors object
+ * @param {Date} startDate - start date
+ * @param {function} [randomDayTimeFn] - function generating random hours and minutes
+ * @returns {String} - The cron definition for trigger
+ */
+export const getCronFromKonnector = (
+  konnector,
+  startDate = new Date(),
+  randomDayTimeFn = randomDayTime
+) =>
+  getCronFromFrequency(konnector.frequency, {
+    ...randomDayTimeFn.apply(
+      null,
+      konnector.time_interval || DEFAULT_TIME_INTERVAL
+    ),
+    dayOfWeek: startDate.getDay(),
+    dayOfMonth: startDate.getDate()
+  })
+
+/**
+ * @typedef {object} randomDayTimeResult
+ * @property {number} hours - hours
+ * @property {number} minutes - minutes
+ */
+
+/**
+ * @typedef {object} FrequencyOptions - frequency options object
+ * @property {Number} [dayOfMonth] - day of the month
+ * @property {Number} [dayOfWeek] - day of the week
+ * @property {Number} [hours] - hours
+ * @property {Number} [minutes] - minutes
+ */