import { CAMPAIGN_RECURRENCES, CAMPAIGN_STATUSES } from "./campaign-form";

export type CampaignRecurrence = (typeof CAMPAIGN_RECURRENCES)[number];
export type CampaignStatus = (typeof CAMPAIGN_STATUSES)[number];

export type CampaignFormRecurrenceInput = {
  recurrence: CampaignRecurrence | (string & {});
  status: CampaignStatus;
  lastRunAt?: number | null;
  now?: number;
};

export type CampaignRunInfo = {
  campaignStatus: CampaignStatus;
  agentRuns?: Array<{
    status: string;
    updatedAt?: number;
  }>;
};

export function isAllowedCampaignRecurrence(value: string): boolean {
  return CAMPAIGN_RECURRENCES.includes(value as CampaignRecurrence);
}

function addDaysUTC(base: number, days: number): number {
  const date = new Date(base);
  return Date.UTC(
    date.getUTCFullYear(),
    date.getUTCMonth(),
    date.getUTCDate() + days,
    date.getUTCHours(),
    date.getUTCMinutes(),
    date.getUTCSeconds(),
    date.getUTCMilliseconds(),
  );
}

function addMonthsUTC(base: number, months: number): number {
  const date = new Date(base);
  return Date.UTC(
    date.getUTCFullYear(),
    date.getUTCMonth() + months,
    date.getUTCDate(),
    date.getUTCHours(),
    date.getUTCMinutes(),
    date.getUTCSeconds(),
    date.getUTCMilliseconds(),
  );
}

export function calculateNextRunAt(input: CampaignFormRecurrenceInput): number | null {
  if (input.status !== "active") {
    return null;
  }

  if (!isAllowedCampaignRecurrence(input.recurrence)) {
    return null;
  }

  if (input.recurrence === "manual") {
    return null;
  }

  const anchor = input.lastRunAt ?? input.now ?? Date.now();
  if (input.recurrence === "daily") {
    return addDaysUTC(anchor, 1);
  }

  if (input.recurrence === "weekly") {
    return addDaysUTC(anchor, 7);
  }

  return addMonthsUTC(anchor, 1);
}

export function getCampaignCurrentRunStatus(input: CampaignRunInfo): string {
  const agentRuns = input.agentRuns ?? [];
  if (agentRuns.length > 0) {
    const ordered = [...agentRuns].sort((a, b) => {
      const aUpdatedAt = typeof a.updatedAt === "number" ? a.updatedAt : 0;
      const bUpdatedAt = typeof b.updatedAt === "number" ? b.updatedAt : 0;

      return bUpdatedAt - aUpdatedAt;
    });

    const latestStatus = ordered.at(0)?.status;
    if (latestStatus === "running") {
      return "running";
    }
    if (latestStatus === "pending") {
      return "pending";
    }
    if (
      latestStatus === "succeeded" ||
      latestStatus === "failed" ||
      latestStatus === "canceled"
    ) {
      return latestStatus;
    }
  }

  return input.campaignStatus === "paused" ? "paused" : "idle";
}