import { db } from '../db/index.js';
import { getHost } from '../hosts/index.js';
import { recordProgress } from './progress.js';
import type { ProvisioningDetail } from '../../provisioning-detail.js';

export const safetyOverrideCapability = 'instance.safety-override';

export function safetyOverride(id: string): ProvisioningDetail['safetyOverride'] {
    return db().prepare(`SELECT actor_id AS actorId, actor_name AS actorName, confirmed_at AS confirmedAt
        FROM provisioning_safety_overrides WHERE deployment_id=?`).get(id) as ProvisioningDetail['safetyOverride'] ?? null;
}

/** Approval belongs to one unsubmitted operation and its original live instance. */
export function safetyOverrideAvailability(id: string): { applicable: boolean; unavailableReason: string | null } {
    const target = db().prepare(`SELECT i.host_id FROM server_deployments d
        JOIN native_provisioning n ON n.deployment_id=d.id
        JOIN native_instances i ON i.id=n.instance_id AND i.server=d.server AND i.generation=n.generation AND i.retired_at IS NULL
        WHERE d.id=? AND d.server_deleted_at IS NULL AND d.action IN ('restart','stop','rebuild','destroy')
        AND d.state IN ('queued','waiting') AND d.submitted_at IS NULL AND n.operation_id IS NULL
        AND NOT EXISTS (SELECT 1 FROM ec_host_migrations m WHERE m.deployment_id=d.id)
        AND NOT EXISTS (SELECT 1 FROM native_creation_cancellations c WHERE c.cleanup_id=d.id)
        AND NOT EXISTS (SELECT 1 FROM autoscaling_decisions a WHERE a.operation_id=d.id)
        AND NOT EXISTS (SELECT 1 FROM provisioning_safety_overrides o WHERE o.deployment_id=d.id)`)
        .get(id) as { host_id: string } | undefined;
    if (!target) return { applicable: false, unavailableReason: null };
    return { applicable: true, unavailableReason: getHost(target.host_id)?.inventory.capabilities?.includes(safetyOverrideCapability)
        ? null : 'Update this host’s agent before using admin override.' };
}

export function enableSafetyOverride(id: string, actor: { id: string; username: string }): { ok: true } | { ok: false; error: string } {
    return db().transaction(() => {
        // A retried confirmation never sends or repeats a command.
        if (safetyOverride(id)) return { ok: true as const };
        const availability = safetyOverrideAvailability(id);
        if (!availability.applicable) return { ok: false as const, error: 'This operation can no longer be overridden. Refresh to see its current state.' };
        if (availability.unavailableReason) return { ok: false as const, error: availability.unavailableReason };
        const confirmedAt = new Date().toISOString();
        db().prepare('INSERT INTO provisioning_safety_overrides(deployment_id,actor_id,actor_name,confirmed_at) VALUES(?,?,?,?)')
            .run(id, actor.id, actor.username, confirmedAt);
        recordProgress(id, { event: { kind: 'safety-override',
            message: `Admin override confirmed by ${actor.username}: bypass player safety checks for this operation.`,
            details: { actorId: actor.id, actorName: actor.username, confirmedAt, checks: ['player-occupancy'] } } });
        return { ok: true as const };
    })();
}