package httpapi

import (
	"errors"
	"net/http"
	"strings"
	"time"

	"git.nianxx.cn/wangxuming/NianAIGC/backend/internal/usage"
)

type UsageReporter = usage.Reporter
type usageHandler struct {
	authorizer *PlatformAuthorizer
	reporter   UsageReporter
	now        func() time.Time
}

func NewUsageHandler(authorizer *PlatformAuthorizer, reporter UsageReporter, now func() time.Time) http.Handler {
	if now == nil {
		now = time.Now
	}
	return &usageHandler{authorizer: authorizer, reporter: reporter, now: now}
}
func (h *usageHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	if r.URL.Path != "/api/usage" && r.URL.Path != "/api/admin/usage" {
		http.NotFound(w, r)
		return
	}
	if !allow(w, r, http.MethodGet) {
		return
	}
	if h.authorizer == nil || h.reporter == nil {
		writeAPIError(w, 500, "服务器内部错误。")
		return
	}
	if r.URL.Path == "/api/usage" {
		h.personal(w, r)
		return
	}
	h.admin(w, r)
}
func (h *usageHandler) personal(w http.ResponseWriter, r *http.Request) {
	session, err := h.authorizer.Authorize(r, PlatformApp)
	if err != nil {
		writeAuthError(w, err)
		return
	}
	preset := usage.Preset(r.URL.Query().Get("preset"))
	switch preset {
	case usage.PresetToday, usage.Preset7Days, usage.Preset30Days, usage.PresetMonth:
	default:
		preset = usage.PresetMonth
	}
	report, err := h.reporter.Personal(r.Context(), usage.PersonalRequest{AccountID: session.User.ID, Preset: preset, Now: h.now()})
	if err != nil {
		writeAPIError(w, 500, "服务器内部错误。")
		return
	}
	writeJSON(w, 200, report)
}
func (h *usageHandler) admin(w http.ResponseWriter, r *http.Request) {
	session, err := h.authorizer.Authorize(r, PlatformAdmin)
	if err != nil {
		writeAuthError(w, err)
		return
	}
	query := r.URL.Query()
	capability, provider := strings.TrimSpace(query.Get("capability")), strings.TrimSpace(query.Get("provider"))
	if capability != "" && capability != "image.generate" && capability != "video.generate" {
		writeAPIError(w, 400, "不支持的功能类型。")
		return
	}
	if provider != "" && provider != "volcengine-visual" && provider != "evolink" && provider != "seedance" && provider != "seedream" && provider != "bailian" && provider != "minimax" {
		writeAPIError(w, 400, "不支持的服务商。")
		return
	}
	startDate, endDate := strings.TrimSpace(query.Get("startDate")), strings.TrimSpace(query.Get("endDate"))
	if !validDate(startDate) || !validDate(endDate) {
		writeAPIError(w, 400, "日期格式无效。")
		return
	}
	request := usage.AdminRequest{Requester: usage.Requester{AccountID: session.User.ID, OrganizationID: session.User.OrganizationID, Role: session.User.Role}, StartDate: startDate, EndDate: endDate, Capability: capability, Provider: provider, Now: h.now()}
	if session.User.Role == "super_admin" {
		request.OrganizationID = strings.TrimSpace(query.Get("organizationId"))
		request.OwnerID = strings.TrimSpace(query.Get("ownerId"))
	} else {
		request.OrganizationID = session.User.OrganizationID
		request.RedactAccounts = true
	}
	report, err := h.reporter.Admin(r.Context(), request)
	if err != nil {
		if errors.Is(err, usage.ErrDateRangeTooLong) {
			writeAPIError(w, 400, "单次查询最多支持 10 年。")
			return
		}
		if errors.Is(err, usage.ErrInvalidDateRange) {
			writeAPIError(w, 400, "开始日期不能晚于结束日期。")
			return
		}
		writeAPIError(w, 500, "服务器内部错误。")
		return
	}
	if request.RedactAccounts {
		report.Accounts = []any{}
		report.Recent = []any{}
		report.Options.Accounts = []usage.Option{}
	}
	writeJSON(w, 200, report)
}
func validDate(value string) bool {
	if value == "" {
		return true
	}
	_, err := time.Parse("2006-01-02", value)
	return err == nil
}