import io
import urllib.parse
from urllib.parse import urlparse

from django.http import JsonResponse
from django.utils import timezone
from django.conf import settings
from django.http import FileResponse, HttpResponseBadRequest
from django.utils.decorators import method_decorator
from django.views import View
from django.views.decorators.csrf import csrf_exempt
from playwright.sync_api import sync_playwright
from django.core.mail import EmailMultiAlternatives
from pdf2image import convert_from_bytes
import base64
from io import BytesIO

charts_map = {
    "UserActivity": {
        "title": "用户活动",
        "path": "/ui/#/reports/users/user-activity"
    }
}


def export_chart_to_pdf(chart_name, sessionid, request=None):
    chart_info = charts_map.get(chart_name)
    if not chart_info:
        return None, None

    if request:
        url = request.build_absolute_uri(urllib.parse.unquote(chart_info['path']))
    else:
        url = urllib.parse.unquote(chart_info['path'])

    if settings.DEBUG_DEV:
        url = url.replace(":8080", ":9528")
    print("Url: ", url)

    with sync_playwright() as p:
        browser = p.chromium.launch(headless=True)
        context = browser.new_context(viewport={"width": 1000, "height": 800})
        # 设置 sessionid cookie
        parsed_url = urlparse(url)
        context.add_cookies([
            {
                'name': settings.SESSION_COOKIE_NAME,
                'value': sessionid,
                'domain': parsed_url.hostname,
                'path': '/',
                'httpOnly': True,
                'secure': False,  # 如有 https 可改 True
            }
        ])
        page = context.new_page()
        try:
            page.goto(url, wait_until='networkidle')
            pdf_bytes = page.pdf(format="A4", landscape=True,
                                 margin={"top": "35px", "bottom": "30px", "left": "20px", "right": "20px"})
        except Exception as e:
            print(f'Playwright error: {e}')
            pdf_bytes = None
        finally:
            browser.close()
        return pdf_bytes, chart_info['title']


@method_decorator(csrf_exempt, name='dispatch')
class ExportPdfView(View):
    def get(self, request):
        chart_name = request.GET.get('chart')
        return self._handle_export(request, chart_name)

    def post(self, request):
        chart_name = request.POST.get('chart')
        return self._handle_export(request, chart_name)

    def _handle_export(self, request, chart_name):
        if not chart_name:
            return HttpResponseBadRequest('Missing chart parameter')
        sessionid = request.COOKIES.get(settings.SESSION_COOKIE_NAME)
        if not sessionid:
            return HttpResponseBadRequest('No sessionid found in cookies')
        
        pdf_bytes, title = export_chart_to_pdf(chart_name, sessionid, request=request)
        if not pdf_bytes:
            return HttpResponseBadRequest('Failed to generate PDF')
        filename = f"{title}-{timezone.now().strftime('%Y%m%d%H%M%S')}.pdf"
        response = FileResponse(io.BytesIO(pdf_bytes), as_attachment=True, filename=filename,
                                content_type='application/pdf')
        return response


class SendMailView(View):
    def get(self, request):
        chart_name = request.GET.get('chart')
        email = "ibuler@qq.com"
        if not chart_name or not email:
            return HttpResponseBadRequest('Missing chart or email parameter')
        sessionid = request.COOKIES.get(settings.SESSION_COOKIE_NAME)
        if not sessionid:
            return HttpResponseBadRequest('No sessionid found in cookies')

        # 1. 生成 PDF
        pdf_bytes, title = export_chart_to_pdf(chart_name, sessionid, request=request)
        if not pdf_bytes:
            return HttpResponseBadRequest('Failed to generate PDF')

        # 2. PDF 转图片
        images = convert_from_bytes(pdf_bytes, dpi=200)
        # 3. 图片转 base64
        img_tags = []
        for img in images:
            buffer = BytesIO()
            img.save(buffer, format="PNG")
            encoded = base64.b64encode(buffer.getvalue()).decode("utf-8")
            img_tags.append(f'<img src="data:image/png;base64,{encoded}" style="width:100%; max-width:800px;" />')
        html_content = "<br/>".join(img_tags)

        # 4. 发送邮件
        subject = f"{title} 报表"
        from_email = settings.EMAIL_HOST_USER
        to = [email]
        msg = EmailMultiAlternatives(subject, '', from_email, to)
        msg.attach_alternative(html_content, "text/html")
        filename = f"{title}-{timezone.now().strftime('%Y%m%d%H%M%S')}.pdf"
        msg.attach(filename, pdf_bytes, "application/pdf")
        msg.send()

        return JsonResponse({"message": "邮件发送成功"})