/**
 * 镭射卡人像抠图 — 网关 POST /api/v1/segment（imageseg / VIAPI）
 * 抠图失败即抛错，中断 thinking，不做椭圆降级。
 */

import { segmentPortraitApi } from '@/utils/api.js'
import { CASTLOVE_FORM_KEY } from '@/utils/castloveGenerationFlow.js'

async function downloadToLocal(url) {
	const target = String(url || '').trim()
	if (!target) {
		throw new Error('缺少抠图下载地址')
	}

	// H5：OSS 跨域时 uni.downloadFile 易丢 PNG alpha，改用 fetch + blob URL
	// #ifdef H5
	const response = await fetch(target)
	if (!response.ok) {
		throw new Error(`下载抠图失败 HTTP ${response.status}`)
	}
	const blob = await response.blob()
	return URL.createObjectURL(blob)
	// #endif

	// #ifndef H5
	return new Promise((resolve, reject) => {
		uni.downloadFile({
			url: target,
			timeout: 120000,
			success: (res) => {
				if (res.statusCode === 200 && res.tempFilePath) {
					resolve(res.tempFilePath)
					return
				}
				reject(new Error(`下载抠图失败 HTTP ${res.statusCode}`))
			},
			fail: (e) => reject(new Error(e?.errMsg || '下载抠图失败')),
		})
	})
	// #endif
}

/** 将抠图本地路径写入 castlove 表单，供 craftMintSubmit 上传 cutout 层 */
export function persistCutoutToForm(cutoutLocalPath, cutoutOssKey = '') {
	try {
		const raw = uni.getStorageSync(CASTLOVE_FORM_KEY)
		if (!raw) return
		const form = typeof raw === 'string' ? JSON.parse(raw) : { ...raw }
		form.cutoutImage = cutoutLocalPath
		if (cutoutOssKey) {
			form.cutout_oss_key = cutoutOssKey
		}
		uni.setStorageSync(CASTLOVE_FORM_KEY, JSON.stringify(form))
	} catch (e) {
		console.warn('[useLaserSegment] persistCutoutToForm failed:', e)
	}
}

export function clearCutoutFromForm() {
	try {
		const raw = uni.getStorageSync(CASTLOVE_FORM_KEY)
		if (!raw) return
		const form = typeof raw === 'string' ? JSON.parse(raw) : { ...raw }
		delete form.cutoutImage
		delete form.cutout_oss_key
		uni.setStorageSync(CASTLOVE_FORM_KEY, JSON.stringify(form))
	} catch (e) {
		/* noop */
	}
}

/**
 * 服务端人像抠图
 * @param {string} imagePath 用户原图本地路径
 * @returns {Promise<{ localPath: string, ossKey: string }>}
 */
export async function segmentPortrait(imagePath, options = {}) {
	const path = String(imagePath || '').trim()
	if (!path) {
		throw new Error('缺少原图')
	}

	const res = await segmentPortraitApi(path, {
		imageBase64: options.imageBase64 || '',
	})
	const data = res?.data
	if (!data?.success || !data?.cutout_url_signed) {
		const msg = data?.message || data?.error_code || 'LC_SEGMENT_FAILED'
		throw new Error(msg)
	}

	const localPath = await downloadToLocal(data.cutout_url_signed)
	persistCutoutToForm(localPath, data.cutout_oss_key || '')
	return {
		localPath,
		ossKey: data.cutout_oss_key || '',
		cutoutUrl: data.cutout_url_signed || '', // OSS 签名的抠图 PNG 地址，供 Dify 使用
	}
}