/**
 * Streak Service - API calls for user streak management
 * 连续记账功能服务
 */

import api from './api';
import type { ApiResponse } from '../types';

/**
 * Streak info returned from backend
 */
export interface StreakInfo {
    current_streak: number;    // 当前连续天数
    longest_streak: number;    // 最长连续记录
    total_record_days: number; // 累计记账天数
    has_record_today: boolean; // 今天是否已记账
    message: string;           // 提示信息
}

/**
 * Daily contribution data
 */
export interface DailyContribution {
    date: string;
    count: number;
}

/**
 * Streak info in camelCase for frontend
 */
export interface StreakInfoFormatted {
    currentStreak: number;
    longestStreak: number;
    totalRecordDays: number;
    hasRecordToday: boolean;
    message: string;
}

/**
 * Map streak data from API (snake_case) to frontend (camelCase)
 */
function mapStreakFromApi(data: StreakInfo): StreakInfoFormatted {
    return {
        currentStreak: data.current_streak,
        longestStreak: data.longest_streak,
        totalRecordDays: data.total_record_days,
        hasRecordToday: data.has_record_today,
        message: data.message,
    };
}

/**
 * Get current user's streak info
 * 获取当前用户的连续记账信息
 */
export async function getStreakInfo(): Promise<StreakInfoFormatted> {
    const response = await api.get<ApiResponse<StreakInfo>>('/user/streak');
    if (!response.data) {
        // Return default values if no streak data
        return {
            currentStreak: 0,
            longestStreak: 0,
            totalRecordDays: 0,
            hasRecordToday: false,
            message: '开始记录你的第一笔账吧！',
        };
    }
    return mapStreakFromApi(response.data);
}

/**
 * Recalculate streak from transaction history
 * 重新计算连续记账天数（基于交易历史）
 */
export async function recalculateStreak(): Promise<StreakInfoFormatted> {
    const response = await api.post<ApiResponse<StreakInfo>>('/user/streak/recalculate');
    if (!response.data) {
        throw new Error(response.error || 'Failed to recalculate streak');
    }
    return mapStreakFromApi(response.data);
}

/**
 * Get daily contribution data for heatmap
 * 获取热力图数据
 */
export async function getContributionData(): Promise<DailyContribution[]> {
    const response = await api.get<ApiResponse<DailyContribution[]>>('/user/streak/contribution');
    return response.data || [];
}

export default {
    getStreakInfo,
    recalculateStreak,
    getContributionData,
};