"""
Simple test to verify CBC solver functionality
"""

import pulp
import sys
import subprocess
import os

print("=== PuLP and CBC Solver Test ===")
print(f"Python version: {sys.version}")
print(f"PuLP version: {pulp.__version__}")

# Test 1: Check PuLP installation
print("\n1. Checking PuLP installation...")
try:
    from pulp import LpProblem, LpVariable, LpMinimize, LpMaximize, lpSum, value

    print("[OK] PuLP imported successfully")
except ImportError as e:
    print(f"[FAIL] PuLP import failed: {e}")
    sys.exit(1)

# Test 2: Check CBC solver file existence
print("\n2. Checking CBC solver file...")
solver_dir = os.path.join(
    os.path.dirname(pulp.__file__), "apis", "..", "solverdir", "cbc", "win", "i64"
)
solver_path = os.path.join(solver_dir, "cbc.exe")

print(f"Looking for CBC at: {solver_path}")
if os.path.exists(solver_path):
    print(f"[OK] CBC solver file found")
    file_size = os.path.getsize(solver_path)
    print(f"  File size: {file_size:,} bytes ({file_size / 1024 / 1024:.2f} MB)")
else:
    print(f"[FAIL] CBC solver file not found")
    print(f"  Checking directory contents:")
    try:
        parent_dir = os.path.dirname(solver_path)
        if os.path.exists(parent_dir):
            for item in os.listdir(parent_dir):
                print(f"    - {item}")
        else:
            print(f"  Directory does not exist: {parent_dir}")
    except Exception as e:
        print(f"  Error listing directory: {e}")

# Test 3: Try to run CBC solver directly
print("\n3. Testing CBC solver execution...")
if os.path.exists(solver_path):
    try:
        result = subprocess.run(
            [solver_path, "-version"],
            capture_output=True,
            text=True,
            timeout=10,
            check=True,
        )
        print("[OK] CBC solver executed successfully")
        print(f"  Output: {result.stdout[:200]}")
    except subprocess.CalledProcessError as e:
        print(f"[FAIL] CBC solver execution failed (exit code {e.returncode})")
        print(f"  stdout: {e.stdout[:200]}")
        print(f"  stderr: {e.stderr[:200]}")
    except subprocess.TimeoutExpired:
        print("[FAIL] CBC solver execution timed out")
    except Exception as e:
        print(f"[FAIL] CBC solver execution error: {e}")
else:
    print("[FAIL] Cannot test CBC execution - file not found")

# Test 4: Solve a simple linear programming problem
print("\n4. Testing simple LP problem...")
try:
    # Simple problem: minimize x + y subject to x + y >= 5, x >= 0, y >= 0
    prob = LpProblem("Simple_LP_Test", LpMinimize)

    x = LpVariable("x", lowBound=0, cat="Continuous")
    y = LpVariable("y", lowBound=0, cat="Continuous")

    prob += x + y  # Objective: minimize x + y
    prob += x + y >= 5  # Constraint

    print("  Created simple LP problem: minimize x + y subject to x + y >= 5")

    # Try to solve with CBC
    solver = pulp.PULP_CBC_CMD(msg=False, timeLimit=10)
    print("  Attempting to solve with CBC...")

    status = prob.solve(solver)

    print(f"[OK] LP problem solved")
    print(f"  Status: {pulp.LpStatus[prob.status]}")
    print(f"  Objective value: {value(prob.objective)}")
    print(f"  x = {value(x)}, y = {value(y)}")

    if abs(value(prob.objective) - 5.0) < 0.01:
        print("  [OK] Correct solution found!")
    else:
        print(f"  [FAIL] Unexpected solution (expected 5.0)")

except Exception as e:
    print(f"[FAIL] LP problem solving failed: {e}")
    import traceback

    traceback.print_exc()

# Test 5: Solve a simple mixed integer programming problem
print("\n5. Testing simple MIP problem...")
try:
    # Simple MIP: minimize x + y subject to x + y >= 5, x, y integers >= 0
    prob = LpProblem("Simple_MIP_Test", LpMinimize)

    x = LpVariable("x", lowBound=0, cat="Integer")
    y = LpVariable("y", lowBound=0, cat="Integer")

    prob += x + y  # Objective
    prob += x + y >= 5  # Constraint

    print(
        "  Created simple MIP problem: minimize x + y subject to x + y >= 5, x,y integers"
    )

    solver = pulp.PULP_CBC_CMD(msg=False, timeLimit=10)
    print("  Attempting to solve with CBC...")

    status = prob.solve(solver)

    print(f"[OK] MIP problem solved")
    print(f"  Status: {pulp.LpStatus[prob.status]}")
    print(f"  Objective value: {value(prob.objective)}")
    print(f"  x = {value(x)}, y = {value(y)}")

    if abs(value(prob.objective) - 5.0) < 0.01:
        print("  [OK] Correct solution found!")
    else:
        print(f"  [FAIL] Unexpected solution (expected 5.0)")

except Exception as e:
    print(f"[FAIL] MIP problem solving failed: {e}")
    import traceback

    traceback.print_exc()

print("\n=== Test Complete ===")