import type {
    Constraint,
    ConstraintContext,
    ConstraintResult,
    RequirementKey,
    StateView,
} from './types.js';

export const evaluateConstraints = (
    constraints: Constraint[],
    ctx: ConstraintContext,
    view: StateView
): ConstraintResult => {
    for (const constraint of constraints) {
        const missing = constraint
            .requires(ctx)
            .filter((req) => !view.has(req));
        if (missing.length > 0 && ctx.mode === 'precheck') {
            return { kind: 'unknown', missing };
        }
        const result = constraint.test(ctx, view);
        if (result.kind !== 'allow') {
            return result;
        }
    }
    return { kind: 'allow' };
};

export const collectRequirements = (
    constraints: Constraint[],
    ctx: ConstraintContext
): RequirementKey[] => {
    const keys: RequirementKey[] = [];
    for (const constraint of constraints) {
        keys.push(...constraint.requires(ctx));
    }
    return keys;
};