import json

from django.contrib import messages
from django.contrib.auth.decorators import login_required
from django.db import transaction
from django.db.models import Count
from django.shortcuts import get_object_or_404, redirect, render

from requirements.llm import analyze_requirements, _default_spec
from requirements.models import Requirement, Submission
from requirements.tasks import run_submission


@login_required
def dashboard(request):
    requirements = Requirement.objects.annotate(sub_count=Count("submissions")).order_by("-created_at")
    recent_submissions = Submission.objects.select_related("requirement").order_by("-created_at")[:15]
    return render(request, "web/dashboard.html", {
        "requirements": requirements,
        "recent_submissions": recent_submissions,
    })


@login_required
def requirement_detail(request, pk):
    requirement = get_object_or_404(Requirement, pk=pk)
    submissions = requirement.submissions.all()
    return render(request, "web/requirement.html", {
        "requirement": requirement,
        "submissions": submissions,
    })


@login_required
def submission_detail(request, pk):
    submission = get_object_or_404(Submission, pk=pk)
    return render(request, "web/submission.html", {
        "submission": submission,
        "report_json": json.dumps(submission.report or {}, ensure_ascii=False, indent=2),
    })


@login_required
def create_requirement(request):
    from django.conf import settings
    if request.method != "POST":
        return render(request, "web/create_requirement.html", {
            "llm_base_url": settings.LLM_BASE_URL,
            "llm_model": settings.LLM_MODEL,
        })
    title = (request.POST.get("title") or "").strip()
    content = (request.POST.get("content") or "").strip()
    if not title or not content:
        messages.error(request, "标题和内容不能为空")
        return redirect("create-requirement")
    llm_mode = request.POST.get("llm_mode", "default")
    override = {}
    if llm_mode == "custom":
        override = {
            "mode": "custom",
            "base_url": (request.POST.get("llm_base_url") or "").strip(),
            "api_key": (request.POST.get("llm_api_key") or "").strip(),
            "model": (request.POST.get("llm_model") or "").strip(),
        }
        if not override["base_url"] or not override["model"]:
            messages.error(request, "custom 模式必须填写 LLM 地址和模型名")
            return redirect("create-requirement")
    try:
        spec = analyze_requirements(content, override)
    except Exception:
        spec = _default_spec()
    with transaction.atomic():
        requirement = Requirement.objects.create(
            title=title, content=content, spec=spec, llm_config=override,
        )
    messages.success(request, f"已创建作业要求「{title}」,AI 分析完成")
    return redirect("requirement-detail", pk=requirement.pk)


@login_required
def upload_submission(request, pk):
    requirement = get_object_or_404(Requirement, pk=pk)
    if request.method != "POST":
        return redirect("requirement-detail", pk=pk)
    file = request.FILES.get("file")
    if not file:
        messages.error(request, "请选择要上传的项目包(tar/tar.gz/zip)")
        return redirect("requirement-detail", pk=pk)
    name = (request.POST.get("name") or "").strip() or file.name
    with transaction.atomic():
        submission = Submission.objects.create(
            requirement=requirement, name=name, file=file, submitted_by=request.user,
        )
    try:
        run_submission(submission.pk)
    except Exception:
        submission.status = "failed"
        submission.save(update_fields=["status"])
    messages.success(request, f"已提交「{name}」,检测完成")
    return redirect("submission-detail", pk=submission.pk)