I have a problem as following:

I have a list of roads to form a network.

Each road has length, speed, and a list of unavailable time slots (start time, end time).

The speed could vary given a list of alternative (start time, end time, speed).

Given a time window(start time, end time), I want to estimate the max time cost for a route (a list of connected roads) within this time window.

Given the start time, I want to calculate the actual time cost for a route.

Any ideas will be highly appreciated.

Cheers