from numpy import *
from FuncDesigner import *

UNDERCONSTRAINED = 0
OVERCONSTRAINED = 1
SOLVED = 2
NO_SOLUTION = 3

class Sketch(object):
    def __init__(self):
        self.shapes = []
        self.constraints = []
        self.num_variables = 0
        self.num_constraints = 0

    def __iter__(self):
        return self.shapes.__iter__()

    def __contains__(self, item):
        return self.shapes.__contains__(item)

    def solve(self):
        shape_vars = {}
        varid_to_shape_var = []
        varid = 0
        equations = []
        for c in self.constraints:
            equations += c.toEqu()
        for e in equations:
            coeffs = e[0]
            for c in coeffs:
                shape_var = c[1]
                if not shape_var in shape_vars:
                    shape_vars[shape_var] = varid
                    varid += 1
                    varid_to_shape_var.append(shape_var)
        self.num_constraints = len(equations)
        self.num_variables = len(shape_vars)
        dim = self.num_constraints
        if self.num_variables > dim:
            dim = self.num_variables
        if self.num_variables < self.num_constraints:
            return OVERCONSTRAINED
        elif self.num_variables > self.num_constraints:
            return UNDERCONSTRAINED
        sle_equs = []
        variables = oovars(dim)
        for e in equations:
            coeffs = e[0]
            equ = -e[1]
            for c in coeffs:
                equ = c[0] * variables[shape_vars[c[1]]] + equ
            sle_equs.append(equ)
        s = sle(sle_equs)
        r = s.solve()
        if r.ff != float('inf'):
#            print "SOLVED: ", r(variables)
            for i in range(len(variables)):
                varid_to_shape_var[i][0].setVar(varid_to_shape_var[i][1],
                        r(variables[i]))
#            for s in self.shapes:
#                print 'shape:', repr(s.vars)
            return SOLVED
        return NO_SOLUTION