show next build time for cron

lib/travis/api/v3/models/cron.rb

@@ -3,5 +3,103 @@ module Travis::API::V3
 
     belongs_to :branch
 
+    def next_build_time
+
+      if disable_by_build
+        if last_non_cron_build_date > last_planned_time
+          return after_next_planned_time
+        else
+          return next_planned_time
+        end
+      else
+        if last_cron_build_date >= last_planned_time
+          return next_planned_time
+        else
+          return Time.now
+        end
+      end
+    end
+
+    def next_planned_time
+      now = DateTime.now
+      created = DateTime.new(created_at.year, created_at.month, created_at.day, created_at.hour)
+      case interval
+      when 'daily'
+        build_today = DateTime.new(now.year, now.month, now.day, created_at.hour)
+        if now > build_today
+          return build_today + 1
+        else
+          return build_today
+        end
+      when 'weekly'
+        build_today = DateTime.new(now.year, now.month, now.day, created_at.hour)
+        in_days = (created_at.wday - now.wday) % 7
+        next_time = build_today + in_days
+        if now > next_time
+          return build_today + 7
+        else
+          return next_time
+        end
+      when 'monthly'
+        month_since_creation = (now.year*12+now.month) - (created_at.year*12+created_at.month)
+        this_month = created >> month_since_creation
+        if now > this_month
+          return created >> (month_since_creation+1)
+        else
+          return this_month
+        end
+      end
+    end
+
+    def last_planned_time
+      now = DateTime.now
+      created = DateTime.new(created_at.year, created_at.month, created_at.day, created_at.hour)
+      case interval
+      when 'daily'
+        return next_planned_time - 1
+      when 'weekly'
+        return next_planned_time - 7
+      when 'monthly'
+        month_since_creation = (now.year*12+now.month) - (created_at.year*12+created_at.month)
+        this_month = created >> month_since_creation
+        if now > this_month
+          return this_month
+        else
+          return created >> (month_since_creation-1)
+        end
+      end
+    end
+
+    def after_next_planned_time
+      now = DateTime.now
+      created = DateTime.new(created_at.year, created_at.month, created_at.day, created_at.hour)
+      case interval
+      when 'daily'
+        return next_planned_time + 1
+      when 'weekly'
+        return next_planned_time + 7
+      when 'monthly'
+        month_since_creation = (now.year*12+now.month) - (created_at.year*12+created_at.month)
+        this_month = created >> month_since_creation
+        if now > this_month
+          return created >> (month_since_creation+2)
+        else
+          return created >> (month_since_creation+1)
+        end
+      end
+    end
+
+    def last_cron_build_date
+      last_cron_build = Models::Build.where(:repository_id => branch.repository.id, :branch => branch.name, :event_type => 'cron').order("id DESC").first
+      return last_cron_build.created_at unless last_cron_build.nil?
+      return Time.at(0)
+    end
+
+    def last_non_cron_build_date
+      last_build = Models::Build.where(:repository_id => branch.repository.id, :branch => branch.name).where(['event_type NOT IN (?)', ['cron']]).order("id DESC").first
+      return last_build.created_at unless last_build.nil?
+      return Time.at(0)
+    end
+
   end
 end

lib/travis/api/v3/renderer.rb

@@ -45,7 +45,7 @@ module Travis::API::V3
       when Hash                   then value.map { |k, v| [k, render_value(v, **options)] }.to_h
       when Array                  then value.map { |v   | render_value(v, **options)      }
       when *PRIMITIVE             then value
-      when Time                   then value.strftime('%Y-%m-%dT%H:%M:%SZ')
+      when Time, DateTime         then value.strftime('%Y-%m-%dT%H:%M:%SZ')
       when Model                  then render_model(value, **options)
       when ActiveRecord::Relation then render_value(value.to_a, **options)
       when ActiveRecord::Associations::CollectionProxy then render_value(value.to_a, **options)

lib/travis/api/v3/renderer/cron.rb

@@ -3,7 +3,7 @@ require 'travis/api/v3/renderer/model_renderer'
 module Travis::API::V3
   class Renderer::Cron < Renderer::ModelRenderer
     representation(:minimal,  :id)
-    representation(:standard, :id, :repository, :branch, :interval, :disable_by_build)
+    representation(:standard, :id, :repository, :branch, :interval, :disable_by_build, :next_build_time)
 
     def repository
       model.branch.repository