"""Early numerical gates; no pass inferred from successful solver exit."""
from pathlib import Path
import json
import numpy as np
from scipy import sparse
from scipy.sparse.linalg import spsolve,eigsh
from components import skew,tube_mesh
from assembly import load,solve,assemble,rz

ROOT=Path(__file__).resolve().parents[1]


def monolithic(chain,deltaT=100.,gravity=(0.,0.,-9.81),rolls=None):
    import basix.ufl
    from agentfem import mesh,models,studies,fields,constitutive
    a=assemble(chain,rolls);points=[];cells=[];lookup={}
    for c,p in zip(chain,a['places']):
        spec=c['spec'];x,t,_=tube_mesh(**{k:v for k,v in spec.items() if k in ['kind','length','radius','diameter','thickness','ns','nt','nr','stub']})
        x=x@p['rotation'].T+p['origin'];ids=[]
        for v in x:
            key=tuple(np.round(v,10))
            if key not in lookup:lookup[key]=len(points);points.append(v)
            ids.append(lookup[key])
        cells.extend(np.asarray(ids)[t])
    domain=mesh.from_arrays(cells=np.asarray(cells),coordinates=np.asarray(points),coordinate_element=basix.ufl.element('Lagrange','hexahedron',1,shape=(3,)))
    model=models.create(study=studies.static_solid(dimension=3),mesh=domain,name='monolithic_L_pipe')
    u=model.field(fields.displacement(domain,degree=2));model.material(constitutive.isotropic_elastic(young=200e9,poisson=.3,density=7850.))
    def mat(op):
        A=op.assemble_matrix();aa,b,v=A.getValuesCSR();out=sparse.csr_matrix((v.copy(),b.copy(),aa.copy()),shape=A.getSize());A.destroy();return out
    K=mat(model.stiffness(u));M=mat(model.mass(u));X=u.function_space.tabulate_dof_coordinates()[:,:3]
    bnodes=np.flatnonzero((abs(X[:,0])<1e-9)&(np.linalg.norm(X,axis=1)<chain[0]['spec']['diameter']));boundary=(bnodes[:,None]*3+np.arange(3)).ravel();free=np.setdiff1d(np.arange(len(X)*3),boundary)
    F=K@(12e-6*X.ravel()*deltaT)+M@np.tile(gravity,len(X))
    w=np.zeros(len(X)*3);w[boundary]=12e-6*X[bnodes].ravel()*deltaT
    w[free]=spsolve(K[free][:,free],(F-K@w)[free])
    end=a['places'][-1]['origin']+a['places'][-1]['rotation']@chain[-1]['ports'][1]
    tangent=a['places'][-1]['rotation'][:,0]
    nodes=np.flatnonzero((abs((X-end)@tangent)<1e-8)&(np.linalg.norm(X-end,axis=1)<chain[-1]['spec']['diameter']))
    tip=w.reshape(-1,3)[nodes].mean(axis=0)
    ev=eigsh(K[free][:,free],k=6,M=M[free][:,free],sigma=0.,return_eigenvectors=False,tol=1e-8)
    return dict(tip=tip.tolist(),frequencies=(np.sqrt(np.sort(ev))/(2*np.pi)).tolist(),dofs=len(w))


def main():
    s=load(ROOT/'data/pilot/straight');e=load(ROOT/'data/pilot/elbow')
    report={}
    for name,c in [('straight',s),('elbow',e)]:
        K=sparse.load_npz(ROOT/f'data/pilot/{name}/stiffness.npz')
        f=c['ftemp'];w=c['wT'];q=(12e-6*c['ports']).reshape(-1,3)
        q12=np.r_[q[0],[0,0,0],q[1],[0,0,0]]
        predicted=c['C']@q12+w
        exact=12e-6*c['xyz'].ravel()
        err=np.linalg.norm(predicted-exact)/np.linalg.norm(exact)
        report[name]={'free_thermal_relative_error':float(err),**c['metrics']}
        assert err<1e-7
        assert c['metrics']['rigid_residual']<1e-9
    chain=[s,e,s]
    result=solve(chain);full=monolithic(chain)
    tip=result['displacements'][-1][-1];ref=np.array(full['tip'])
    report['assembly']={'rom_tip':tip.tolist(),'full_tip':full['tip'],
        'tip_relative_error':float(np.linalg.norm(tip-ref)/np.linalg.norm(ref)),
        'rom_frequencies':result['frequency'].tolist(),'full_frequencies':full['frequencies'],
        'frequency_relative_errors':(abs(result['frequency']/full['frequencies']-1)).tolist(),
        'free_residual':result['free_residual'],'reference_dofs':full['dofs']}
    out=ROOT/'reports';out.mkdir(exist_ok=True)
    (out/'pilot.json').write_text(json.dumps(report,indent=2))
    print(json.dumps(report,indent=2))


if __name__=='__main__':main()