Build a Task Management System

I want a task management system, build on a PHP framework like Laravel or CMS like Joomla. My requirements are: 1) Ability to assign someone task (task will show in both the assigner n assignee screen) 2) Ability to assign a task which is already assigned to me. 3) Prioritise tasks (high medium low) 4) Custom task sequencing 5) User’s ability to show how much task is complete (% wise) 6) Project based allocation, here user will be assigned to a project and multiple task given under each project (project is like a group of task which can be closed afterwards) 7) Attachments 8) Categories of task (like finance, marketing, operations, etc. etc) 9) Reporting on who was involved for how much time in a task and who took how much time to complete a task 10) Reporting like day wise summary, to give me how much busy or free a person is (efficiency), as each person has to write the number of hours spend on a task. 11) Ability to share task (a task assigned to multiple people) 12) Notifications over email and SMS. 13) Internal forum to discuss on a task. (each thread for each task) 14) Build on a open source CMS platform (like wordpress or joomla) without modifying the core files 15) Users hierarchy settings, in which a top level user can assign tasks to any user under him, however the bottom level can assign task to one level up also. (this has to be discussed in detail) 16) Various task status like Done/Not started/Pending/In process/Left etc.