import { useCallback, useEffect, useState } from "react";
import type { Entry } from "@/lib/shared/types";
import { recurringEntriesCreate, recurringEntriesDelete, recurringEntriesList, recurringEntriesUpdate } from "@/lib/client/recurring-entries";
import type { ApiResult } from "@/lib/client/fetch-json";

type CreateRecurringEntryInput = {
    entryType: "SPENDING" | "INCOME";
    amountDollars: number;
    occurredAt: string;
    necessity: "NECESSARY" | "BOTH" | "UNNECESSARY";
    purchaseType: string;
    notes?: string;
    tags?: string[];
    bucketId?: number | null;
    frequency?: "DAILY" | "WEEKLY" | "BIWEEKLY" | "MONTHLY" | "QUARTERLY" | "YEARLY" | null;
    intervalCount?: number;
    endCondition?: "NEVER" | "AFTER_COUNT" | "BY_DATE" | null;
    endCount?: number | null;
    endDate?: string | null;
    nextRunAt?: string | null;
};

type UpdateRecurringEntryInput = CreateRecurringEntryInput & { id: number };

export default function useRecurringEntries(activeGroupId?: number | null) {
    const [entries, setEntries] = useState<Entry[]>([]);
    const [loading, setLoading] = useState(true);
    const [error, setError] = useState("");

    function isError<T>(result: ApiResult<T>): result is { error: { code: string; message: string } } {
        return "error" in result;
    }

    const load = useCallback(async () => {
        if (!activeGroupId) {
            setError("");
            setEntries([]);
            setLoading(false);
            return;
        }
        setLoading(true);
        setError("");
        const result = await recurringEntriesList();
        if (isError(result)) {
            setError(result.error.message || "");
            setEntries([]);
        } else {
            setEntries(result.data.entries || []);
        }
        setLoading(false);
    }, [activeGroupId]);

    const createEntry = useCallback(async (input: CreateRecurringEntryInput) => {
        setError("");
        const result = await recurringEntriesCreate(input);
        if (isError(result)) {
            setError(result.error.message || "");
            return false;
        }
        await load();
        return true;
    }, [load]);

    const updateEntry = useCallback(async (input: UpdateRecurringEntryInput) => {
        setError("");
        const result = await recurringEntriesUpdate(input);
        if (isError(result)) {
            setError(result.error.message || "");
            return false;
        }
        await load();
        return true;
    }, [load]);

    const deleteEntry = useCallback(async (id: number | string) => {
        setError("");
        const result = await recurringEntriesDelete({ id });
        if (isError(result)) {
            setError(result.error.message || "");
            return false;
        }
        await load();
        return true;
    }, [load]);

    useEffect(() => {
        load();
    }, [load]);

    return {
        entries,
        loading,
        error,
        createEntry,
        updateEntry,
        deleteEntry,
        reload: load
    };
}