from __future__ import annotations

from itertools import combinations

from pydantic import BaseModel, Field

from .models import SafetyPolicy, SwarmSolution


class VerificationReport(BaseModel):
    passed: bool
    violations: list[str] = Field(default_factory=list)


def verify_swarm_solution(solution: SwarmSolution, policy: SafetyPolicy) -> VerificationReport:
    violations: list[str] = []
    robots = solution.robots

    for robot in robots:
        if not policy.verify(robot.initial_pos, robot.current_pos):
            violations.append(f"{robot.robot_id}: travel bound exceeded")
        if robot.travel_distance > policy.energy_budget:
            violations.append(f"{robot.robot_id}: energy budget exceeded")

    for left, right in combinations(robots, 2):
        if abs(left.current_pos - right.current_pos) < policy.min_separation:
            violations.append(
                f"{left.robot_id}/{right.robot_id}: separation below {policy.min_separation}"
            )

    if not solution.certificate.converged:
        violations.append("solver did not converge")

    return VerificationReport(passed=not violations, violations=violations)