Bar chart for Job Schedule report

Hello,

i have requirement of creating a bar chart report. here is the scenario.

we have employees and their jobcode. so for a single given day an employee can work on different jobcodes for a given specific amount of time. so i need to create a report which will display as 

y-axis--> employee name

then 

x-axis --> time interval of 30 minutes starting with say 7am till 5pm

 then on the detail side

if an employee1 started on JOB1 at 9am for 30 min so the record should fall under that section.

if an employee2 started on JOB2 at 12pm for 2 hrs so the record should fall under that section.

there is maximum of 5 job codes.

the table structure is not yet finalized ... once this scenario is possible then we can finalized the table structure...

please help me...

thanks.