export interface FleetSettings {
    deployKeepDays: number;
    observationKeepDays: number;
    restartConcurrency: number;
    createConcurrency: number;
    destroyConcurrency: number;
}

export const defaultFleetSettings: FleetSettings = {
    deployKeepDays: 7,
    observationKeepDays: 1,
    restartConcurrency: 1,
    createConcurrency: 1,
    destroyConcurrency: 1
};

export const fleetSettingLabels: Record<keyof FleetSettings, string> = {
    deployKeepDays: 'Campaign history retention',
    observationKeepDays: 'Routine operation history retention',
    restartConcurrency: 'Concurrent restarts',
    createConcurrency: 'Concurrent server startups',
    destroyConcurrency: 'Concurrent server destructions'
};

export function validateFleetSettings(input: unknown): FleetSettings {
    if (!input || typeof input !== 'object' || Array.isArray(input)) throw new Error('Provide fleet settings.');
    const values = input as Record<string, unknown>;
    for (const key of Object.keys(values)) {
        if (!Object.hasOwn(defaultFleetSettings, key)) throw new Error(`Unknown setting: ${key}`);
    }
    for (const key of Object.keys(defaultFleetSettings) as (keyof FleetSettings)[]) {
        const value = values[key];
        const minimum = key === 'observationKeepDays' ? 0 : 1;
        if (typeof value !== 'number' || !Number.isSafeInteger(value) || value < minimum) {
            throw new Error(`${fleetSettingLabels[key]} must be ${minimum === 0 ? 'zero or a positive whole number' : 'a positive whole number'}.`);
        }
        if ((key === 'deployKeepDays' || key === 'observationKeepDays') && value > 36500) {
            throw new Error(`${fleetSettingLabels[key]} must be at most 36500 days.`);
        }
    }
    return { deployKeepDays: values.deployKeepDays as number, observationKeepDays: values.observationKeepDays as number, restartConcurrency: values.restartConcurrency as number,
        createConcurrency: values.createConcurrency as number, destroyConcurrency: values.destroyConcurrency as number };
}