import { requestJson } from '@/services/api.uts'
import { acceptSession } from './auth.uts'

export function wechatLoginSupported(): boolean {
    // App微信SDK及各平台应用凭据接入后再开放原生入口。
    // #ifdef MP-WEIXIN
    return true
    // #endif
    // #ifndef MP-WEIXIN
    return false
    // #endif
}

export function requestWechatAuthorization(): Promise<string> {
    // #ifdef MP-WEIXIN
    return new Promise<string>((resolve, reject) => {
        uni.login({
            provider: 'weixin',
            success: (result) => {
                const code = result.code
                if (code.length == 0) { reject(new Error('未能取得微信登录凭证，请重新操作')); return }
                resolve(code)
            },
            fail: (error) => {
                const cancelled = error.errMsg.toLowerCase().includes('cancel') || error.errCode == 1310509
                reject(new Error(cancelled ? '已取消微信登录' : '微信授权失败，请重新操作'))
            }
        })
    })
    // #endif
    // #ifndef MP-WEIXIN
    return new Promise<string>((resolve, reject) => {
        reject(new Error('当前平台暂未开放微信登录，请使用手机号登录'))
    })
    // #endif
}

function validTicket(value: string): boolean { return /^[A-Za-z0-9_-]{32,128}$/.test(value) }
function validPhone(value: string): boolean { return /^1[3-9][0-9]{9}$/.test(value) }

function validateResult(result: UTSJSONObject): UTSJSONObject {
    const status = result.getString('status') ?? ''
    if (status == 'bind_required') {
        const expires = result.getNumber('expiresIn') ?? 0
        if (!validTicket(result.getString('bindingTicket') ?? '') || expires < 1 || expires > 600 || Math.floor(expires) != expires || result['token'] != null)
            throw new Error('微信绑定响应格式不完整，请重新微信登录')
    } else if (status == 'authenticated') {
        const expiry = Date.parse(result.getString('expiresAt') ?? '')
        if (result.getBoolean('consentsConfirmed') != true || !validPhone(result.getString('phone') ?? '')
            || !/^[1-9][0-9]{0,18}$/.test(result.getString('userId') ?? '') || (result.getString('token') ?? '').length == 0
            || isNaN(expiry) || expiry <= Date.now()) throw new Error('微信登录响应缺少有效账户或协议确认')
    } else throw new Error('微信登录响应状态无效')
    return result
}

export async function requestWechatLogin(code: string, agreements: UTSJSONObject[]): Promise<UTSJSONObject> {
    if (code.length == 0 || code.length > 256 || agreements.length != 2) throw new Error('请重新确认协议并微信登录')
    let terms = false; let privacy = false; let previousRequestId = ''
    for (const item of agreements) {
        const agreementCode = item['agreementCode'] as string | null ?? ''
        const requestId = item['requestId'] as string | null ?? ''
        if ((agreementCode == 'terms' && !terms)) terms = true
        else if ((agreementCode == 'privacy' && !privacy)) privacy = true
        else throw new Error('用户协议和隐私政策必须分别确认')
        if (!/^[A-Za-z0-9][A-Za-z0-9._-]{0,63}$/.test(item['agreementVersion'] as string | null ?? '')
            || !/^[a-f0-9]{64}$/.test(item['contentHash'] as string | null ?? '') || !/^[A-Za-z0-9_-]{16,64}$/.test(requestId)
            || requestId == previousRequestId) throw new Error('协议确认信息不完整，请重新阅读并确认')
        previousRequestId = requestId
    }
    return validateResult(await requestJson('/auth/wechat-login', 'POST', { platform: 'mp-weixin', code, agreements }))
}

export async function requestWechatBindingCode(bindingTicket: string, phone: string): Promise<boolean> {
    if (!validTicket(bindingTicket) || !validPhone(phone)) throw new Error('请重新微信登录并输入正确手机号')
    await requestJson('/auth/wechat/sms-code', 'POST', { bindingTicket, phone })
    return true
}

export async function bindWechatPhone(bindingTicket: string, phone: string, code: string): Promise<UTSJSONObject> {
    if (!validTicket(bindingTicket) || !validPhone(phone) || !/^[0-9]{6}$/.test(code)) throw new Error('请核对手机号和6位验证码')
    const result = validateResult(await requestJson('/auth/wechat/bind-phone', 'POST', { bindingTicket, phone, code }))
    if (result.getString('status') != 'authenticated') throw new Error('手机号绑定尚未完成，请重新微信登录')
    return result
}

export function acceptWechatSession(result: UTSJSONObject): string {
    validateResult(result)
    if (result.getString('status') != 'authenticated') throw new Error('请先完成手机号绑定')
    return acceptSession(result, result.getString('phone') ?? '')
}