Advanced: Scheduled Price Changes, with Mechanic.

mechanic/user/text
user/price_changes/start
user/price_changes/end
user/price_changes/reset

{% assign email_recipients = options.notification_email_recipients__array_required %}
{% assign event_start_datetime = options.event_start_datetime__required %}
{% assign event_end_datetime = options.event_end_datetime__required %}
{% assign set_compare_at_prices = options.set_compare_at_prices_to_original_price_during_event__boolean %}
{% assign collection_handles_and_discounts = options.collection_handles_and_discounts__keyval %}
{% assign skus_to_include = options.skus_to_include__array %}
{% assign sku_discount = options.sku_discount %}
{% assign exclude_products_tagged_with = options.exclude_products_tagged_with__array %}
{% assign skus_to_exclude = options.skus_to_exclude__array %}
{% assign do_not_restore_prices_on_reset = options.do_not_restore_prices_on_reset__boolean %}

{%- capture task_admin_link -%}
  <a href="https://{{ shop.myshopify_domain }}/admin/apps/mechanic/~/tasks/edit/{{ task.id }}">{{ task.name | remove: "ADVANCED: " }}</a>
{%- endcapture -%}

{% comment %}
  -- query for shop data on every task run, since it will be needed for each valid action keyword and custom event
{% endcomment %}

{% capture query %}
  query {
    shop {
      id
      name
      contactEmail
      metafield(key: "mechanic.price_change_events") {
        jsonValue
      }
    }
  }
{% endcapture %}

{% assign result = query | shopify %}

{% if event.preview %}
  {% capture result_json %}
    {
      "data": {
        "shop": {
          "id": "gid://shopify/Shop/1234567890",
          "name": "Shoplify",
          "contactEmail": "info@example.com",
          "metafield": {
            "jsonValue": {
              "price_change_event__1234567890": {
                "status": "scheduled",
                "start": "2025-12-30 08:00",
                "end": "2025-12-31 20:00",
                "set_compare_at_prices": true,
                "collection_handles_and_discounts": {
                  "collection-alpha": "20%",
                  "collection-beta": "-10",
                  "collection-gamma": "20"
                },
                "skus_to_include": [],
                "sku_discount": "",
                "skus_to_exclude": [],
                "exclude_products_tagged_with": [
                  "clearance"
                ]
              }
            }
          }
        }
      }
    }
  {% endcapture %}

  {% assign result = result_json | parse_json %}
{% endif %}

{% assign shop = result.data.shop %}
{% assign price_change_events = shop.metafield.jsonValue | default: hash %}

{% if event.topic == "mechanic/user/text" %}
  {% comment %}
    -- check text entry to see what action to take
  {% endcomment %}

  {% assign action_keyword = event.data | downcase %}

  {% if event.preview %}
    {% assign action_keyword = "schedule" %}
  {% endif %}

  {% case action_keyword %}
    {% when "schedule" %}
      {% comment %}
        -- NOTE: run scheduling logic here instead of in custom event like most other keywords, so user gets immediate feedback on any configuration errors
      {% endcomment %}

      {% assign valid_start_datetime = event_start_datetime | parse_date: "%Y-%m-%d %H:%M" %}

      {% if valid_start_datetime == blank %}
        {% assign valid_start_datetime = event_start_datetime | parse_date: "%Y-%m-%d" %}

        {% if valid_start_datetime == blank %}
          {% unless event.preview %}
            {% error "The event start date is not a valid date. Please re-enter it (per the task documentation) and try scheduling the event again." %}
            {% break %}
          {% endunless %}
        {% endif %}
      {% endif %}

      {% assign valid_end_datetime = event_end_datetime | parse_date: "%Y-%m-%d %H:%M" %}

      {% if valid_end_datetime == blank %}
        {% assign valid_end_datetime = event_end_datetime | parse_date: "%Y-%m-%d" %}

        {% if valid_end_datetime == blank %}
          {% unless event.preview %}
            {% error "The event end date is not a valid date. Please re-enter it (per the task documentation) and try scheduling the event again." %}
            {% break %}
          {% endunless %}
        {% endif %}
      {% endif %}

      {% assign now_s = "now" | date: "%s" %}
      {% assign start_datetime_s = event_start_datetime | date: "%s" %}
      {% assign end_datetime_s = event_end_datetime | date: "%s" %}

      {% if start_datetime_s <= now_s or start_datetime_s >= end_datetime_s %}
        {% unless event.preview %}
          {% error "The event start and end dates must be future dates and the start date must be before the end date. Please re-enter them (per the task documentation) and try scheduling the event again." %}
          {% break %}
        {% endunless %}
      {% endif %}

      {% comment %}
        -- validate discount entry formats: XX% (percentage discount), X.XX (fixed price), or -X.XX (fixed discount)
      {% endcomment %}

      {% assign discounts = collection_handles_and_discounts | values | default: array %}

      {% if skus_to_include != blank and sku_discount == blank %}
        {% unless event.preview %}
          {% error "A SKU discount must be configured when specific SKUs are included." %}
          {% break %}
        {% endunless %}
      {% endif %}

      {% if sku_discount != blank %}
        {% assign discounts = discounts | push: sku_discount %}
      {% endif %}

      {% for discount in discounts %}
        {% if discount contains "%" %}
          {% assign discount_percentage = discount | times: 1 %}
          {% assign discount_string = discount_percentage | append: "%" %}

          {% if discount != discount_string %}
            {% unless event.preview %}
              {% error
                message: "Percentage discount entry incorrect. Please update the task configuration (per the task documentation) and try scheduling the event again.",
                discount: discount
              %}
              {% break %}
            {% endunless %}
          {% endif %}

          {% if discount_percentage <= 0 or discount_percentage >= 100 %}
            {% unless event.preview %}
              {% error
                message: "Percentage discount entries should contain an number between 0 and 100. Please update the task configuration (per the task documentation) and try scheduling the event again.",
                discount: discount
              %}
              {% break %}
            {% endunless %}
          {% endif %}

        {% else %}
          {% assign discount_absolute = discount | times: 1 | abs %}

          {% if discount_absolute == 0 %}
            {% unless event.preview %}
              {% error
                message: "Fixed price and fixed discount entries must contain an absolute number > 0. Please update the task configuration (per the task documentation) and try scheduling the event again.",
                discount: discount
              %}
              {% break %}
            {% endunless %}
          {% endif %}
        {% endif %}
      {% endfor %}

      {% assign price_change_event = hash %}

      {% assign price_change_event["status"] = "scheduled" %}
      {% assign price_change_event["start"] = start_datetime_s | date: "%FT%H:%M%z" %}
      {% assign price_change_event["end"] = end_datetime_s | date: "%FT%H:%M%z" %}
      {% assign price_change_event["set_compare_at_prices"] = set_compare_at_prices %}
      {% assign price_change_event["collection_handles_and_discounts"] = collection_handles_and_discounts %}
      {% assign price_change_event["skus_to_include"] = skus_to_include %}
      {% assign price_change_event["sku_discount"] = sku_discount %}
      {% assign price_change_event["skus_to_exclude"] = skus_to_exclude %}
      {% assign price_change_event["exclude_products_tagged_with"] = exclude_products_tagged_with %}

      {% log
        task_options: task.options,
        price_change_event: price_change_event
      %}

      {% assign price_change_event_id = event.id | default: task.id %}

      {% assign price_change_events[price_change_event_id] = price_change_event %}

      {% action "shopify" %}
        mutation {
          metafieldsSet(
            metafields: [
              {
                ownerId: {{ shop.id | json }}
                namespace: "mechanic"
                key: "price_change_events"
                value: {{ price_change_events | json | json }}
                type: "json"
              }
            ]
          ) {
            metafields {
              id
              namespace
              key
              type
              jsonValue
              owner {
                ... on Shop {
                  id
                  name
                  myshopifyDomain
                }
              }
            }
            userErrors {
              code
              field
              message
            }
          }
        }
      {% endaction %}

      {% comment %}
        -- schedule start and end events
      {% endcomment %}

      {% action "event" %}
        {
          "topic": "user/price_changes/start",
          "task_id": {{ task.id | json }},
          "run_at": {{ start_datetime_s | json }},
          "data": {
            "price_change_event_id": {{ price_change_event_id | json }}
          }
        }
      {% endaction %}

      {% action "event" %}
        {
          "topic": "user/price_changes/end",
          "task_id": {{ task.id | json }},
          "run_at": {{ end_datetime_s | json }},
          "data": {
            "price_change_event_id": {{ price_change_event_id | json }}
          }
        }
      {% endaction %}

      {% capture email_subject %}New price change event scheduled ({{ price_change_event_id }}){% endcapture %}

      {% capture email_body %}
        A new price change event has been scheduled, from the {{ task_admin_link }} task within the Mechanic app.

        <strong>Price change event ID:</strong> {{ price_change_event_id }}
        <strong>Status:</strong> {{ price_change_event["status"] }}
        <strong>Event start:</strong> {{ price_change_event["start"] | date: "%FT%H:%M%z" }}
        <strong>Event end:</strong> {{ price_change_event["end"] | date: "%FT%H:%M%z" }}
        <strong>Set compare at price to original price during event:</strong> {{ price_change_event["set_compare_at_prices"] }}
        <strong>Collection handles and discounts:</strong>
        {% for keyval in price_change_event["collection_handles_and_discounts"] -%}
        - {{ keyval[0] }}: {{ keyval[1] }}
        {% else -%}
          n/a
        {%- endfor %}
        <strong>SKUs to include:</strong> {{ price_change_event["skus_to_include"] | join: ", " | default: "n/a" }}
        <strong>SKU discount:</strong> {{ price_change_event["sku_discount"] | default: "n/a" }},
        <strong>SKUs to exclude:</strong> {{ price_change_event["skus_to_exclude"] | join: ", " | default: "n/a" }}
        <strong>Exclude products tagged with:</strong> {{ price_change_event["exclude_products_tagged_with"] | join: ", " | default: "n/a" }}

        <em><strong>Note:</strong> To cancel this event while it is still scheduled or ongoing, use the "cancel" keyword along with the price change event ID when running the task.</em>
      {% endcapture %}

      {% action "email" %}
        {
          "to": {{ email_recipients | json }},
          "subject": {{ email_subject | json }},
          "body": {{ email_body | newline_to_br | json }},
          "reply_to": {{ shop.contactEmail | json }},
          "from_display_name": {{ shop.name | json }}
        }
      {% endaction %}

    {% when "list" %}
      {% action "echo" price_change_events: price_change_events %}

    {% when "email" %}
      {% if price_change_events == blank %}
        {% assign email_body = "There are currently no configured price change events" %}

      {% else %}
        {% capture email_body %}
          Currently configured price change events, using the {{ task_admin_link }} task within the Mechanic app.

          {% for price_change_event in price_change_events -%}
            {%- assign price_change_event_id = price_change_event[0] -%}
            {%- assign price_change_event_data = price_change_event[1] -%}
            <strong>Price change event ID:</strong> {{ price_change_event_id }}
            <strong>Status:</strong> {{ price_change_event_data["status"] }}
            <strong>Event start:</strong> {{ price_change_event_data["start"] | date: "%FT%H:%M%z" }}
            <strong>Event end:</strong> {{ price_change_event_data["end"] | date: "%FT%H:%M%z" }}
            <strong>Set compare at price to original price during event:</strong> {{ price_change_event_data["set_compare_at_prices"] }}
            <strong>Collection handles and discounts:</strong>
            {% for keyval in price_change_event_data["collection_handles_and_discounts"] -%}
            - {{ keyval[0] }}: {{ keyval[1] }}
            {% else -%}
              n/a
            {%- endfor %}
            <strong>SKUs to include:</strong> {{ price_change_event_data["skus_to_include"] | join: ", " | default: "n/a" }}
            <strong>SKU discount:</strong> {{ price_change_event_data["sku_discount"] | default: "n/a" }},
            <strong>SKUs to exclude:</strong> {{ price_change_event_data["skus_to_exclude"] | join: ", " | default: "n/a" }}
            <strong>Exclude products tagged with:</strong> {{ price_change_event_data["exclude_products_tagged_with"] | join: ", " | default: "n/a" }}
            <hr />
          {%- endfor %}
        {% endcapture %}
      {% endif %}

      {% action "email" %}
        {
          "to": {{ email_recipients | json }},
          "subject": "All price change events as of {{ "now" | date: "%F" }}",
          "body": {{ email_body | newline_to_br | json }},
          "reply_to": {{ shop.contactEmail | json }},
          "from_display_name": {{ shop.name | json }}
        }
      {% endaction %}

    {% when "reset" %}
      {% action "event" %}
        {
          "topic": "user/price_changes/reset",
          "task_id": {{ task.id | json }}
        }
      {% endaction %}

    {% else %}
      {% if action_keyword contains "cancel" %}
        {% assign price_change_event_id = action_keyword | remove: "cancel " %}
        {% assign price_change_event = price_change_events[price_change_event_id] %}

        {% if price_change_event == blank %}
          {% error "Keyword of 'cancel' entered with an invalid price change event ID. Run task with 'list' keyword to see a list of all configured price change events." %}
          {% break %}
        {% endif %}

        {% if price_change_event.status == "scheduled" %}
          {% comment %}
            -- price change event has not started, so can just update it to cancelled and when the start/end events run they will ignore this event
          {% endcomment %}

          {% assign price_change_event["status"] = "cancelled" %}
          {% assign price_change_events[price_change_event_id] = price_change_event %}

          {% action "shopify" %}
            mutation {
              metafieldsSet(
                metafields: [
                  {
                    ownerId: {{ shop.id | json }}
                    namespace: "mechanic"
                    key: "price_change_events"
                    value: {{ price_change_events | json | json }}
                    type: "json"
                  }
                ]
              ) {
                metafields {
                  id
                  namespace
                  key
                  type
                  jsonValue
                  owner {
                    ... on Shop {
                      id
                      name
                      myshopifyDomain
                    }
                  }
                }
                userErrors {
                  code
                  field
                  message
                }
              }
            }
          {% endaction %}

          {% capture email_subject %}Scheduled price change event has been cancelled ({{ price_change_event_id }}){% endcapture %}

          {% capture email_body %}
            A scheduled price change event has been cancelled, from the {{ task_admin_link }} task within the Mechanic app.

            <strong>Price change event ID:</strong> {{ price_change_event_id }}
            <strong>Status:</strong> {{ price_change_event["status"] }}
            <strong>Event start:</strong> {{ price_change_event["start"] | date: "%FT%H:%M%z" }}
            <strong>Event end:</strong> {{ price_change_event["end"] | date: "%FT%H:%M%z" }}
            <strong>Set compare at price to original price during event:</strong> {{ price_change_event["set_compare_at_prices"] }}
            <strong>Collection handles and discounts:</strong>
            {% for keyval in price_change_event["collection_handles_and_discounts"] -%}
            - {{ keyval[0] }}: {{ keyval[1] }}
            {% else -%}
              n/a
            {%- endfor %}
            <strong>SKUs to include:</strong> {{ price_change_event["skus_to_include"] | join: ", " | default: "n/a" }}
            <strong>SKU discount:</strong> {{ price_change_event["sku_discount"] | default: "n/a" }},
            <strong>SKUs to exclude:</strong> {{ price_change_event["skus_to_exclude"] | join: ", " | default: "n/a" }}
            <strong>Exclude products tagged with:</strong> {{ price_change_event["exclude_products_tagged_with"] | join: ", " | default: "n/a" }}
          {% endcapture %}

          {% action "email" %}
            {
              "to": {{ email_recipients | json }},
              "subject": {{ email_subject | json }},
              "body": {{ email_body | newline_to_br | json }},
              "reply_to": {{ shop.contactEmail | json }},
              "from_display_name": {{ shop.name | json }}
            }
          {% endaction %}

        {% elsif price_change_event.status == "ongoing" %}
          {% comment %}
            -- price change event in progress, so we have to revert the price changes to properly cancel it
          {% endcomment %}

          {% action "event" %}
            {
              "topic": "user/price_changes/end",
              "task_id": {{ task.id | json }},
              "data": {
                "price_change_event_id": {{ price_change_event_id | json }},
                "cancel": true
              }
            }
          {% endaction %}

        {% else %}
          {% action "echo"
            message: "Price change event cannot be cancelled because it does not have a status of 'scheduled' or 'ongoing'",
            price_change_event: price_change_event
          %}
        {% endif %}

      {% else %}
        {% error
          message: "Unrecognized action keyword. Action keyword must be one of 'schedule', 'list', 'email', or 'cancel'",
          action_keyword: action_keyword
        %}
      {% endif %}
  {% endcase %}

{% elsif event.topic == "user/price_changes/start" %}
  {% assign price_change_event_id = event.data.price_change_event_id %}
  {% assign price_change_event = price_change_events[price_change_event_id] %}

  {% if event.preview %}
    {% assign price_change_event_id = "01234567-89ab-cdef" %}

    {% capture price_change_event_json %}
      {
        "status": "scheduled",
        "start": {{ "now + 1 day" | date: "%FT%H:%M%z" | json }},
        "end": {{ "now + 2 days" | date: "%FT%H:%M%z" | json }},
        "set_compare_at_prices": false,
        "collection_handles_and_discounts": {
          "alpha-beta-gamma": "10%",
          "sticks-and-stones": "-5.50",
          "lorem-ipsum": "3"
        },
        "skus_to_include": [
          "SKU-123",
          "SKU-456"
        ],
        "sku_discount": "15%",
        "skus_to_exclude": [
          "SKU-987"
        ],
        "exclude_products_tagged_with": [
          "do-not-discount"
        ]
      }
    {% endcapture %}

    {% assign price_change_event = price_change_event_json | parse_json %}
  {% endif %}

  {% assign status = price_change_event.status %}
  {% assign set_compare_at_prices = price_change_event.set_compare_at_prices %}
  {% assign collection_handles_and_discounts = price_change_event.collection_handles_and_discounts %}
  {% assign skus_to_include = price_change_event.skus_to_include %}
  {% assign sku_discount = price_change_event.sku_discount %}
  {% assign exclude_products_tagged_with = price_change_event.exclude_products_tagged_with %}
  {% assign skus_to_exclude = price_change_event.skus_to_exclude %}

  {% if status != "scheduled" %}
    {% log
      message: "This price change event does not have a status of scheduled, and thus will not start.",
      price_change_event: price_change_event
    %}
    {% break %}
  {% endif %}

  {% comment %}
    -- get collection ids for products query
  {% endcomment %}

  {% assign in_collection_checks = array %}

  {% for keyval in collection_handles_and_discounts %}
    {% capture query %}
      query {
        collectionByHandle(handle: {{ keyval[0] | json }}) {
          id
          handle
        }
      }
    {% endcapture %}

    {% assign result = query | shopify %}

    {% assign collection = result.data.collectionByHandle %}

    {% if collection != blank %}
      {% capture in_collection_check -%}
        inCollection_{{ collection.handle | replace: "-", "_" }}: inCollection(id: {{ collection.id | json }})
      {%- endcapture %}

      {% assign in_collection_checks = in_collection_checks | push: in_collection_check %}
    {% endif %}
  {% endfor %}

  {% comment %}
    -- get all products in the shop (up to 50K), unless excluded by tag
  {% endcomment %}

  {% assign search_query = "gift_card:false" %}

  {% for tag in exclude_products_tagged_with %}
    {% assign search_query = tag | json | prepend: " tag_not:" | prepend: search_query  %}
  {% endfor %}

  {% log search_query: search_query %}

  {% assign products = array %}
  {% assign cursor = nil %}

  {% for n in (1..200) %}
    {% capture query %}
      query {
        products(
          first: 250
          after: {{ cursor | json }}
          query: {{ search_query | json }}
        ) {
          pageInfo {
            hasNextPage
            endCursor
          }
          nodes {
            id
            title
            tags
            variants(first: 100) {
              nodes {
                id
                displayName
                sku
                price
                compareAtPrice
                metafield(key: "mechanic.price_change_event") {
                  jsonValue
                }
              }
            }
            {{ in_collection_checks | join: newline }}
          }
        }
      }
    {% endcapture %}

    {% assign result = query | shopify %}

    {% if event.preview %}
      {% capture result_json %}
        {
          "data": {
            "products": {
              "nodes": [
                {
                  "id": "gid://shopify/Product/1234567890",
                  "variants": {
                    "nodes": [
                      {
                        "id": "gid://shopify/ProductVariant/1234567890",
                        "sku": "ACME-BRICK-RED",
                        "price": "10.00",
                        "compareAtPrice": "15.00",
                        "metafield": null
                      }
                    ]
                  },
                  "inCollection_{{ collection_handles_and_discounts.first.first | replace: "-", "_" | default: "sample" }}": true
                }
              ]
            }
          }
        }
      {% endcapture %}

      {% assign result = result_json | parse_json %}
    {% endif %}

    {% assign products = products | concat: result.data.products.nodes %}

    {% if result.data.products.pageInfo.hasNextPage %}
      {% assign cursor = result.data.products.pageInfo.endCursor %}
    {% else %}
      {% break %}
    {% endif %}
  {% endfor %}

  {% comment %}
    -- process products to see which qualify for metafield and variant updates
  {% endcomment %}

  {% assign metafield_set_inputs = array %}
  {% assign variant_inputs_by_product = hash %}

  {% for product in products %}
    {% comment %}
      -- For each product, match to a collection discount if applicable, then, if needed, loop through variants to see if there are any overrides
    {% endcomment %}

    {% assign product_level_discount = nil %}

    {% for keyval in collection_handles_and_discounts %}
      {% assign in_collection_label
        = "inCollection_"
        | append: keyval[0]
        | replace: "-", "_"
      %}

      {% if product[in_collection_label] %}
        {% assign product_level_discount = keyval[1] %}
        {% break %}
      {% endif %}
    {% endfor %}

    {% if product_level_discount == blank and skus_to_include == blank and skus_to_exclude == blank %}
      {% comment %}
        -- skip the product if it is not in a configured collection and there are no inclusion/exclusion SKUs configured
      {% endcomment %}

      {% continue %}
    {% endif %}

    {% for variant in product.variants.nodes %}
      {% if skus_to_exclude != blank and skus_to_exclude contains variant.sku %}
        {% log
          message: "This variant was excluded by SKU",
          variant: variant
        %}
        {% continue %}
      {% endif %}

      {% if variant.metafield != blank %}
        {% log
          message: "This variant is already part of a price change event; skipping.",
          variant: variant
        %}
        {% continue %}
      {% endif %}

      {% assign discount_to_apply = product_level_discount %}

      {% if skus_to_include != blank and skus_to_include contains variant.sku %}
        {% assign discount_to_apply = sku_discount %}
      {% endif %}

      {% if discount_to_apply == blank %}
        {% continue %}
      {% endif %}

      {% comment %}
        -- make sure prices are strings when being passed in GraphQL mutations
      {% endcomment %}

      {% assign price_to_set = nil %}
      {% assign compare_at_price_to_set = nil %}

      {% if discount_to_apply contains "%" %}
        {% assign price_to_set
          = discount_to_apply
          | remove: "%"
          | minus: 100
          | abs
          | times: variant.price
          | divided_by: 100
          | round: 2
          | append: ""
        %}

      {% elsif discount_to_apply contains "-" %}
        {% assign price_to_set
          = variant.price
          | plus: discount_to_apply
          | at_least: 0.0
          | append: ""
        %}

      {% else %}
        {% assign price_to_set = discount_to_apply | append: "" %}
      {% endif %}

      {% if set_compare_at_prices %}
        {% assign compare_at_price_to_set = variant.price %}
      {% endif %}

      {% log
        product: product.title,
        product_level_discount: product_level_discount,
        variant: variant.displayName,
        discount_to_apply: discount_to_apply,
        price_to_set: price_to_set,
        compare_at_price_to_set: compare_at_price_to_set
      %}

      {% assign price_change_event_data = hash %}
      {% assign price_change_event_data["price_change_event_id"] = price_change_event_id %}
      {% assign price_change_event_data["discount_to_apply"] = discount_to_apply %}
      {% assign price_change_event_data["original_price"] = variant.price %}
      {% assign price_change_event_data["price_to_set"] = price_to_set %}

      {% if set_compare_at_prices %}
        {% assign price_change_event_data["original_compare_at_price"] = variant.compareAtPrice %}
        {% assign price_change_event_data["compare_at_price_to_set"] = compare_at_price_to_set %}
      {% endif %}

      {% assign metafield_set_input = hash %}
      {% assign metafield_set_input["ownerId"] = variant.id %}
      {% assign metafield_set_input["namespace"] = "mechanic" %}
      {% assign metafield_set_input["key"] = "price_change_event" %}
      {% assign metafield_set_input["type"] = "json" %}
      {% assign metafield_set_input["value"] = price_change_event_data | json %}
      {% assign metafield_set_inputs = metafield_set_inputs | push: metafield_set_input %}

      {% assign variant_input = hash %}
      {% assign variant_input["id"] = variant.id %}
      {% assign variant_input["price"] = price_to_set %}

      {% if set_compare_at_prices %}
        {% assign variant_input["compareAtPrice"] = variant.price %}
      {% endif %}

      {% assign variant_inputs_by_product[product.id]
        = variant_inputs_by_product[product.id]
        | default: array
        | push: variant_input
      %}
    {% endfor %}
  {% endfor %}

  {% comment %}
    -- set metafields and then update variants in bulk
  {% endcomment %}

  {% if metafield_set_inputs != blank %}
    {% assign groups_of_metafield_set_inputs = metafield_set_inputs | in_groups_of: 25, fill_with: false %}

    {% for group_of_metafield_set_inputs in groups_of_metafield_set_inputs %}
      {% action "shopify" %}
        mutation {
          metafieldsSet(
            metafields: {{ group_of_metafield_set_inputs | graphql_arguments }}
          ) {
            metafields {
              id
              namespace
              key
              type
              jsonValue
              owner {
                ... on ProductVariant {
                  id
                  displayName
                }
              }
            }
            userErrors {
              code
              field
              message
            }
          }
        }
      {% endaction %}
    {% endfor %}
  {% endif %}

  {% for keyval in variant_inputs_by_product %}
    {% action "shopify" %}
      mutation {
        productVariantsBulkUpdate(
          productId: {{ keyval[0] | json }}
          variants: {{ keyval[1] | graphql_arguments }}
        ) {
          product {
            id
            title
            tags
          }
          productVariants {
            id
            displayName
            sku
            price
            compareAtPrice
          }
          userErrors {
            field
            message
          }
        }
      }
    {% endaction %}
  {% endfor %}

  {% comment %}
    -- update the price change event
  {% endcomment %}

  {% assign price_change_event["status"] = "ongoing" %}
  {% assign price_change_events[price_change_event_id] = price_change_event %}

  {% action "shopify" %}
    mutation {
      metafieldsSet(
        metafields: [
          {
            ownerId: {{ shop.id | json }}
            namespace: "mechanic"
            key: "price_change_events"
            value: {{ price_change_events | json | json }}
            type: "json"
          }
        ]
      ) {
        metafields {
          id
          namespace
          key
          type
          jsonValue
          owner {
            ... on Shop {
              id
              name
              myshopifyDomain
            }
          }
        }
        userErrors {
          code
          field
          message
        }
      }
    }
  {% endaction %}

  {% capture email_subject %}A scheduled price change event has started ({{ price_change_event_id }}){% endcapture %}

  {% capture email_body %}
    A scheduled price change event has started, using the {{ task_admin_link }} task within the Mechanic app.

    <strong>Price change event ID:</strong> {{ price_change_event_id }}
    <strong>Status:</strong> {{ price_change_event["status"] }}
    <strong>Event start:</strong> {{ price_change_event["start"] | date: "%FT%H:%M%z" }}
    <strong>Event end:</strong> {{ price_change_event["end"] | date: "%FT%H:%M%z" }}
    <strong>Set compare at price to original price during event:</strong> {{ price_change_event["set_compare_at_prices"] }}
    <strong>Collection handles and discounts:</strong>
    {% for keyval in price_change_event["collection_handles_and_discounts"] -%}
    - {{ keyval[0] }}: {{ keyval[1] }}
    {% else -%}
      n/a
    {%- endfor %}
    <strong>SKUs to include:</strong> {{ price_change_event["skus_to_include"] | join: ", " | default: "n/a" }}
    <strong>SKU discount:</strong> {{ price_change_event["sku_discount"] | default: "n/a" }},
    <strong>SKUs to exclude:</strong> {{ price_change_event["skus_to_exclude"] | join: ", " | default: "n/a" }}
    <strong>Exclude products tagged with:</strong> {{ price_change_event["exclude_products_tagged_with"] | join: ", " | default: "n/a" }}

    <em><strong>Note:</strong> To cancel this event while it is ongoing, use the "cancel" keyword along with the price change event ID when running the task.</em>
  {% endcapture %}

  {% action "email" %}
    {
      "to": {{ email_recipients | json }},
      "subject": {{ email_subject | json }},
      "body": {{ email_body | newline_to_br | json }},
      "reply_to": {{ shop.contactEmail | json }},
      "from_display_name": {{ shop.name | json }}
    }
  {% endaction %}

{% elsif event.topic == "user/price_changes/end" %}
  {% assign price_change_event_id = event.data.price_change_event_id %}
  {% assign price_change_event = price_change_events[price_change_event_id] %}

  {% if event.preview %}
    {% assign price_change_event_id = "01234567-89ab-cdef" %}
    {% assign price_change_event = hash %}
    {% assign price_change_event["status"] = "ongoing" %}
  {% endif %}

  {% if event.data.cancel %}
    {% comment %}
      -- go ahead and cancel, as status was already checked to be "scheduled" prior to custom event call
    {% endcomment %}

    {% assign price_change_event["status"] = "cancelled" %}

  {% else %}
    {% comment %}
      -- since this was a scheduled run, need to make sure the event status is "ongoing" before reverting changes
    {% endcomment %}

    {% if price_change_event.status != "ongoing" %}
      {% log
        message: "This price change event does not have a status of 'ongoing', and thus will not be reverted.",
        price_change_event: price_change_event
      %}
      {% break %}
    {% endif %}

    {% assign price_change_event["status"] = "completed" %}
  {% endif %}

  {% comment %}
    -- To revert the price change event, check every variant in the shop to see if the metafield exists and contains this price change event ID
  {% endcomment %}

  {% assign products = array %}
  {% assign cursor = nil %}

  {% for n in (1..200) %}
    {% capture query %}
      query {
        products(
          first: 250
          after: {{ cursor | json }}
          query: "gift_card:false"
        ) {
          pageInfo {
            hasNextPage
            endCursor
          }
          nodes {
            id
            title
            tags
            variants(first: 100) {
              nodes {
                id
                displayName
                sku
                price
                compareAtPrice
                metafield(key: "mechanic.price_change_event") {
                  jsonValue
                }
              }
            }
          }
        }
      }
    {% endcapture %}

    {% assign result = query | shopify %}

    {% if event.preview %}
      {% capture result_json %}
        {
          "data": {
            "products": {
              "nodes": [
                {
                  "id": "gid://shopify/Product/1234567890",
                  "variants": {
                    "nodes": [
                      {
                        "id": "gid://shopify/ProductVariant/1234567890",
                        "sku": "ACME-BRICK-RED",
                        "price": "7.50",
                        "compareAtPrice": "10.00",
                        "metafield": {
                          "id": "gid://shopify/Metafield/9876543210",
                          "jsonValue": {
                            "price_change_event_id": "01234567-89ab-cdef",
                            "discount_to_apply": "25%",
                            "original_price": "10.00",
                            "price_to_set": "7.50",
                            "original_compare_at_price": "15.00",
                            "compare_at_price_to_set": "7.50"
                          }
                        }
                      }
                    ]
                  }
                }
              ]
            }
          }
        }
      {% endcapture %}

      {% assign result = result_json | parse_json %}
    {% endif %}

    {% assign products = products | concat: result.data.products.nodes %}

    {% if result.data.products.pageInfo.hasNextPage %}
      {% assign cursor = result.data.products.pageInfo.endCursor %}
    {% else %}
      {% break %}
    {% endif %}
  {% endfor %}

  {% comment %}
    -- process products to see which qualify for metafield deletion and variant price reversion
  {% endcomment %}

  {% assign metafield_delete_inputs = array %}
  {% assign variant_inputs_by_product = hash %}

  {% for product in products %}
    {% assign variants_with_metafield = product.variants.nodes | where: "metafield" %}

    {% for variant in variants_with_metafield %}
      {% assign price_change_event_data = variant.metafield.jsonValue %}

      {% unless price_change_event_data.price_change_event_id == price_change_event_id %}
        {% log
          message: "This variant is part of a separate price change event; skipping.",
          variant: variant
        %}
        {% continue %}
      {% endunless %}

      {% assign metafield_delete_input = hash %}
      {% assign metafield_delete_input["ownerId"] = variant.id %}
      {% assign metafield_delete_input["namespace"] = "mechanic" %}
      {% assign metafield_delete_input["key"] = "price_change_event" %}
      {% assign metafield_delete_inputs = metafield_delete_inputs | push: metafield_delete_input %}

      {% assign variant_input = hash %}
      {% assign variant_input["id"] = variant.id %}

      {% assign original_price = price_change_event_data.original_price | append: "" %}
      {% assign original_compare_at_price = price_change_event_data.original_compare_at_price | append: "" %}

      {% if original_price != variant.price %}
        {% assign variant_input["price"] = original_price %}
      {% endif %}

      {% if original_compare_at_price != blank and original_compare_at_price != variant.compareAtPrice %}
        {% assign variant_input["compareAtPrice"] = original_compare_at_price %}
      {% endif %}

      {% if variant_input["price"] or variant_input["compareAtPrice"] %}
        {% assign variant_inputs_by_product[product.id]
          = variant_inputs_by_product[product.id]
          | default: array
          | push: variant_input
        %}
      {% endif %}
    {% endfor %}
  {% endfor %}

  {% comment %}
    -- update variants in bulk and then delete the price change event metafields
  {% endcomment %}

  {% for keyval in variant_inputs_by_product %}
    {% action "shopify" %}
      mutation {
        productVariantsBulkUpdate(
          productId: {{ keyval[0] | json }}
          variants: {{ keyval[1] | graphql_arguments }}
        ) {
          product {
            id
            title
            tags
          }
          productVariants {
            id
            displayName
            sku
            price
            compareAtPrice
          }
          userErrors {
            field
            message
          }
        }
      }
    {% endaction %}
  {% endfor %}

  {% if metafield_delete_inputs != blank %}
    {% assign groups_of_metafield_delete_inputs = metafield_delete_inputs | in_groups_of: 250, fill_with: false %}

    {% for group_of_metafield_delete_inputs in groups_of_metafield_delete_inputs %}
      {% action "shopify" %}
        mutation {
          metafieldsDelete(
            metafields: {{ group_of_metafield_delete_inputs | graphql_arguments }}
          ) {
            deletedMetafields {
              ownerId
              namespace
              key
            }
            userErrors {
              field
              message
            }
          }
        }
      {% endaction %}
    {% endfor %}
  {% endif %}

  {% comment %}
    -- update the price change event
  {% endcomment %}

  {% assign price_change_events[price_change_event_id] = price_change_event %}

  {% action "shopify" %}
    mutation {
      metafieldsSet(
        metafields: [
          {
            ownerId: {{ shop.id | json }}
            namespace: "mechanic"
            key: "price_change_events"
            value: {{ price_change_events | json | json }}
            type: "json"
          }
        ]
      ) {
        metafields {
          id
          namespace
          key
          type
          value
          owner {
            ... on Shop {
              id
              name
              myshopifyDomain
            }
          }
        }
        userErrors {
          code
          field
          message
        }
      }
    }
  {% endaction %}

  {% comment %}
    -- send email notification about the price change event status change
  {% endcomment %}

  {% capture email_subject %}A price change event has been {{ price_change_event["status"] }} ({{ price_change_event_id }}){% endcapture %}

  {% capture email_body %}
    A price change event has been {{ price_change_event["status"] }}, using the {{ task_admin_link }} task within the Mechanic app.

    <strong>Price change event ID:</strong> {{ price_change_event_id }}
    <strong>Status:</strong> {{ price_change_event["status"] }}
    <strong>Event start:</strong> {{ price_change_event["start"] | date: "%FT%H:%M%z" }}
    <strong>Event end:</strong> {{ price_change_event["end"] | date: "%FT%H:%M%z" }}
    <strong>Set compare at price to original price during event:</strong> {{ price_change_event["set_compare_at_prices"] }}
    <strong>Collection handles and discounts:</strong>
    {% for keyval in price_change_event["collection_handles_and_discounts"] -%}
    - {{ keyval[0] }}: {{ keyval[1] }}
    {% else -%}
      n/a
    {%- endfor %}
    <strong>SKUs to include:</strong> {{ price_change_event["skus_to_include"] | join: ", " | default: "n/a" }}
    <strong>SKU discount:</strong> {{ price_change_event["sku_discount"] | default: "n/a" }},
    <strong>SKUs to exclude:</strong> {{ price_change_event["skus_to_exclude"] | join: ", " | default: "n/a" }}
    <strong>Exclude products tagged with:</strong> {{ price_change_event["exclude_products_tagged_with"] | join: ", " | default: "n/a" }}
  {% endcapture %}

  {% action "email" %}
    {
      "to": {{ email_recipients | json }},
      "subject": {{ email_subject | json }},
      "body": {{ email_body | newline_to_br | json }},
      "reply_to": {{ shop.contactEmail | json }},
      "from_display_name": {{ shop.name | json }}
    }
  {% endaction %}

{% elsif event.topic == "user/price_changes/reset" %}
  {% comment %}
    -- To reset price change events, check every variant in the shop to see if the price change event metafield exists
  {% endcomment %}

  {% assign products = array %}
  {% assign cursor = nil %}

  {% for n in (1..200) %}
    {% capture query %}
      query {
        products(
          first: 250
          after: {{ cursor | json }}
          query: "gift_card:false"
        ) {
          pageInfo {
            hasNextPage
            endCursor
          }
          nodes {
            id
            title
            tags
            variants(first: 100) {
              nodes {
                id
                displayName
                sku
                price
                compareAtPrice
                metafield(key: "mechanic.price_change_event") {
                  jsonValue
                }
              }
            }
          }
        }
      }
    {% endcapture %}

    {% assign result = query | shopify %}

    {% if event.preview %}
      {% capture result_json %}
        {
          "data": {
            "products": {
              "nodes": [
                {
                  "id": "gid://shopify/Product/1234567890",
                  "variants": {
                    "nodes": [
                      {
                        "id": "gid://shopify/ProductVariant/1234567890",
                        "sku": "ACME-BRICK-RED",
                        "price": "7.50",
                        "compareAtPrice": "10.00",
                        "metafield": {
                          "id": "gid://shopify/Metafield/9876543210",
                          "jsonValue": {
                            "price_change_event_id": "01234567-89ab-cdef",
                            "discount_to_apply": "25%",
                            "original_price": "10.00",
                            "price_to_set": "7.50",
                            "original_compare_at_price": "15.00",
                            "compare_at_price_to_set": "7.50"
                          }
                        }
                      }
                    ]
                  }
                }
              ]
            }
          }
        }
      {% endcapture %}

      {% assign result = result_json | parse_json %}
    {% endif %}

    {% assign products = products | concat: result.data.products.nodes %}

    {% if result.data.products.pageInfo.hasNextPage %}
      {% assign cursor = result.data.products.pageInfo.endCursor %}
    {% else %}
      {% break %}
    {% endif %}
  {% endfor %}

  {% comment %}
    -- process products to see which qualify for metafield deletion and variant price reversion
  {% endcomment %}

  {% assign metafield_delete_inputs = array %}
  {% assign variant_inputs_by_product = hash %}
  {% assign variants_with_prices_to_not_reset = array %}

  {% for product in products %}
    {% assign variants_with_metafield = product.variants.nodes | where: "metafield" %}

    {% for variant in variants_with_metafield %}
      {% assign price_change_event_data = variant.metafield.jsonValue %}

      {% assign metafield_delete_input = hash %}
      {% assign metafield_delete_input["ownerId"] = variant.id %}
      {% assign metafield_delete_input["namespace"] = "mechanic" %}
      {% assign metafield_delete_input["key"] = "price_change_event" %}
      {% assign metafield_delete_inputs = metafield_delete_inputs | push: metafield_delete_input %}

      {% if do_not_restore_prices_on_reset %}
        {% assign variants_with_prices_to_not_reset = variants_with_prices_to_not_reset | push: variant %}
        {% continue %}
      {% endif %}

      {% assign variant_input = hash %}
      {% assign variant_input["id"] = variant.id %}

      {% assign original_price = price_change_event_data.original_price | append: "" %}
      {% assign original_compare_at_price = price_change_event_data.original_compare_at_price | append: "" %}

      {% if original_price != variant.price %}
        {% assign variant_input["price"] = original_price %}
      {% endif %}

      {% if original_compare_at_price != blank and original_compare_at_price != variant.compareAtPrice %}
        {% assign variant_input["compareAtPrice"] = original_compare_at_price %}
      {% endif %}

      {% if variant_input["price"] or variant_input["compareAtPrice"] %}
        {% assign variant_inputs_by_product[product.id]
          = variant_inputs_by_product[product.id]
          | default: array
          | push: variant_input
        %}
      {% endif %}
    {% endfor %}
  {% endfor %}

  {% comment %}
    -- update variant prices in bulk (unless opting not to) and then delete the price change event metafields
  {% endcomment %}

  {% if do_not_restore_prices_on_reset %}
    {% log
      do_not_restore_prices_on_reset: do_not_restore_prices_on_reset,
      variants_with_prices_to_not_reset: variants_with_prices_to_not_reset
    %}

  {% else %}
    {% for keyval in variant_inputs_by_product %}
      {% action "shopify" %}
        mutation {
          productVariantsBulkUpdate(
            productId: {{ keyval[0] | json }}
            variants: {{ keyval[1] | graphql_arguments }}
          ) {
            product {
              id
              title
              tags
            }
            productVariants {
              id
              displayName
              sku
              price
              compareAtPrice
            }
            userErrors {
              field
              message
            }
          }
        }
      {% endaction %}
    {% endfor %}
  {% endif %}

  {% if metafield_delete_inputs != blank %}
    {% assign groups_of_metafield_delete_inputs = metafield_delete_inputs | in_groups_of: 250, fill_with: false %}

    {% for group_of_metafield_delete_inputs in groups_of_metafield_delete_inputs %}
      {% action "shopify" %}
        mutation {
          metafieldsDelete(
            metafields: {{ group_of_metafield_delete_inputs | graphql_arguments }}
          ) {
            deletedMetafields {
              ownerId
              namespace
              key
            }
            userErrors {
              field
              message
            }
          }
        }
      {% endaction %}
    {% endfor %}
  {% endif %}

  {% comment %}
    -- delete the price change events shop metafield if needed
  {% endcomment %}

  {% if shop.metafield != blank %}
    {% action "shopify" %}
      mutation {
        metafieldsDelete(
          metafields: [
            {
              ownerId: {{ shop.id | json }}
              namespace: "mechanic"
              key: "price_change_events"
            }
          ]
        ) {
          deletedMetafields {
            ownerId
            namespace
            key
          }
          userErrors {
            field
            message
          }
        }
      }
    {% endaction %}
  {% endif %}

  {% comment %}
    -- send email notification about the price change events reset
  {% endcomment %}

  {% capture email_subject %}All price change events have been cleared{% endcapture %}

  {% capture email_body %}
    {% if do_not_restore_prices_on_reset %}
      All price change events have been cleared, using the {{ task_admin_link }} task within the Mechanic app.
    {% else %}
      All price change events have been cleared and related prices reset, using the {{ task_admin_link }} task within the Mechanic app.
    {% endif %}
  {% endcapture %}

  {% action "email" %}
    {
      "to": {{ email_recipients | json }},
      "subject": {{ email_subject | json }},
      "body": {{ email_body | newline_to_br | json }},
      "reply_to": {{ shop.contactEmail | json }},
      "from_display_name": {{ shop.name | json }}
    }
  {% endaction %}
{% endif %}