package handlers

import (
	"net/http"
	"time"

	"github.com/gin-gonic/gin"

	"qr-scanner/config"
	"qr-scanner/models"
	"qr-scanner/services"
)

type ScanHandler struct {
	cfg     config.Config
	store   *services.TaskStore
	scanner *services.Scanner
}

func NewScanHandler(cfg config.Config, store *services.TaskStore, scanner *services.Scanner) *ScanHandler {
	return &ScanHandler{cfg: cfg, store: store, scanner: scanner}
}

func (h *ScanHandler) StartScan(c *gin.Context) {
	var req models.ScanRequest
	if err := c.ShouldBindJSON(&req); err != nil || req.TaskID == "" {
		fail(c, http.StatusBadRequest, "请求参数错误")
		return
	}

	task, ok := h.store.Get(req.TaskID)
	if !ok {
		fail(c, http.StatusNotFound, "任务不存在")
		return
	}

	if task.Status == services.TaskExpired {
		fail(c, http.StatusGone, "任务已过期")
		return
	}

	concurrency := req.Concurrency
	if concurrency <= 0 {
		concurrency = h.cfg.DefaultWorkers
	}
	if concurrency <= 0 {
		concurrency = 1
	}
	if h.cfg.MaxWorkers > 0 && concurrency > h.cfg.MaxWorkers {
		concurrency = h.cfg.MaxWorkers
	}

	timeout := req.Timeout
	if timeout <= 0 {
		timeout = h.cfg.DefaultTimeoutS
	}
	if timeout <= 0 {
		timeout = 30
	}
	if h.cfg.MaxTimeoutS > 0 && timeout > h.cfg.MaxTimeoutS {
		timeout = h.cfg.MaxTimeoutS
	}

	task.Concurrency = concurrency
	task.TimeoutS = timeout
	task.UpdatedAt = time.Now()
	h.store.Put(task)

	_ = h.scanner.Start(task)
	respondOK(c, models.ScanStartResponse{TaskID: task.ID, Status: string(task.Status)})
}