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#![allow(non_upper_case_globals)]
#![allow(non_camel_case_types)]
#![allow(non_snake_case)]

include!(concat!(env!("OUT_DIR"), "/bindings.rs"));

#[cfg(test)]
mod tests {
    use super::Highs_call;
    use std::os::raw::c_int;
    use std::convert::TryInto;

    #[test]
    fn highs_call() {
        // This illustrates the use of Highs_call, the simple C interface to
        // HiGHS. It's designed to solve the general LP problem
        //
        // Min c^Tx subject to L <= Ax <= U; l <= x <= u
        //
        // where A is a matrix with m rows and n columns
        //
        // The scalar n is numcol
        // The scalar m is numrow
        //
        // The vector c is colcost
        // The vector l is collower
        // The vector u is colupper
        // The vector L is rowlower
        // The vector U is rowupper
        //
        // The matrix A is represented in packed column-wise form: only its
        // nonzeros are stored
        //
        // * The number of nonzeros in A is nnz
        //
        // * The row indices of the nonnzeros in A are stored column-by-column
        // in aindex
        //
        // * The values of the nonnzeros in A are stored column-by-column in
        // avalue
        //
        // * The position in aindex/avalue of the index/value of the first
        // nonzero in each column is stored in astart
        //
        // Note that astart[0] must be zero
        //
        // After a successful call to Highs_call, the primal and dual
        // solution, and the simplex basis are returned as follows
        //
        // The vector x is colvalue
        // The vector Ax is rowvalue
        // The vector of dual values for the variables x is coldual
        // The vector of dual values for the variables Ax is rowdual
        // The basic/nonbasic status of the variables x is colbasisstatus
        // The basic/nonbasic status of the variables Ax is rowbasisstatus
        //
        // The status of the solution obtained is modelstatus
        //
        // To solve maximization problems, the values in c must be negated
        //
        // The use of Highs_call is illustrated for the LP
        //
        // Min    f  = 2x_0 + 3x_1
        // s.t.                x_1 <= 6
        //       10 <=  x_0 + 2x_1 <= 14
        //        8 <= 2x_0 +  x_1
        // 0 <= x_0 <= 3; 1 <= x_1

        let numcol: usize = 2;
        let numrow: usize = 3;
        let nnz: usize = 5;

        // Define the column costs, lower bounds and upper bounds
        let colcost: &mut [f64] = &mut [2.0, 3.0];
        let collower: &mut [f64] = &mut [0.0, 1.0];
        let colupper: &mut [f64] = &mut [3.0, 1.0e30];
        // Define the row lower bounds and upper bounds
        let rowlower: &mut [f64] = &mut [-1.0e30, 10.0, 8.0];
        let rowupper: &mut [f64] = &mut [6.0, 14.0, 1.0e30];
        // Define the constraint matrix column-wise
        let astart: &mut [c_int] = &mut [0, 2];
        let aindex: &mut [c_int] = &mut [1, 2, 0, 1, 2];
        let avalue: &mut [f64] = &mut [1.0, 2.0, 1.0, 2.0, 1.0];

        let colvalue: &mut [f64] = &mut vec![0.; numcol];
        let coldual: &mut [f64] = &mut vec![0.; numcol];
        let rowvalue: &mut [f64] = &mut vec![0.; numrow];
        let rowdual: &mut [f64] = &mut vec![0.; numrow];

        let colbasisstatus: &mut [c_int] = &mut vec![0; numcol];
        let rowbasisstatus: &mut [c_int] = &mut vec![0; numrow];

        let modelstatus: &mut c_int = &mut 0;

        let status: c_int = unsafe {
            Highs_call(
                numcol.try_into().unwrap(),
                numrow.try_into().unwrap(),
                nnz.try_into().unwrap(),
                colcost.as_mut_ptr(),
                collower.as_mut_ptr(),
                colupper.as_mut_ptr(),
                rowlower.as_mut_ptr(),
                rowupper.as_mut_ptr(),
                astart.as_mut_ptr(),
                aindex.as_mut_ptr(),
                avalue.as_mut_ptr(),
                colvalue.as_mut_ptr(),
                coldual.as_mut_ptr(),
                rowvalue.as_mut_ptr(),
                rowdual.as_mut_ptr(),
                colbasisstatus.as_mut_ptr(),
                rowbasisstatus.as_mut_ptr(),
                modelstatus
            )
        };

        assert_eq!(status, 0);
        assert_eq!(colvalue, &[2., 4.]);
    }
}