using DelimitedFiles, Plots
include("../ho_basis_3body_resonance.jl")

current_E = 5.9673 - 0.0006im

training_c = 2.0 : -0.2 : 1.2
extrapolating_c = 1.05 .- [0.0 : 0.1 : 0.4; 0.45 : 0.05 : 0.60]

@time "H0" H0 = T1 + T2

# free memory
basis = T1 = T2 = V1_cache = V_relative_cache = V1 = V_relative = U = V2 = nothing
GC.gc()

exact = ComplexF64[]
training = ComplexF64[]
extrapolated = ComplexF64[]
training_vecs = Vector{ComplexF64}[]

for c in training_c
    println("Training for c = $c")
    local H = H0 + c .* V
    local evals, evecs = eigs(H, nev=3, ncv=24, which=:LI, maxiter=5000, tol=1e-5, ritzvec=true, check=1)

    global current_E = nearest(evals, current_E)
    push!(training, current_E)
    push!(training_vecs, evecs[:, nearestIndex(evals, current_E)])
end

println("Original EC dimensionality = $(length(training_vecs))")
@time "Gram-Schmidt" training_vecs = gram_schmidt!(training_vecs; verbose=true) # orthonormalization

EC_basis = hcat(training_vecs...)
H0_EC = transpose(EC_basis) * H0 * EC_basis
V_EC = transpose(EC_basis) * V * EC_basis

for c in extrapolating_c
    println("Extrapolating for c = $c")
    local H = H0 + c .* V
    local evals, evecs = eigs(H, nev=3, ncv=24, which=:LI, maxiter=5000, tol=1e-5, ritzvec=true, check=1)

    global current_E = nearest(evals, current_E)
    push!(exact, current_E)

    # extrapolation
    H_EC = H0_EC + c .* V_EC
    evals = eigvals(H_EC)
    push!(extrapolated, nearest(evals, current_E))
end

exportCSV("temp/NCSM.csv", (training, exact, extrapolated), ("training", "exact", "extrapolated"))

scatter(real.(training),imag.(training), label="training")
scatter!(real.(exact),imag.(exact), label="exact")
scatter!(real.(extrapolated),imag.(extrapolated), label="extrapolated")
savefig("temp/NCSM.pdf")