package controllers

import (
	"encoding/json"
	"io"
	"strings"

	"server/pkg/identity"
	"server/pkg/jwtutil"
	"server/services/wechatmini"

	beego "github.com/beego/beego/v2/server/web"
)

// AppMiniSubscribeController 小程序订阅消息（uniapp 调用）
//
// 订阅消息是「用户 → 授权 → 服务器主动推给用户」的链路：
//  1. GET  /api/mini/subscribe/templates   取当前可订阅的模板（含模板ID与跳转页）
//  2. 小程序端调 uni.requestSubscribeMessage 弹授权窗，用户同意后
//  3. POST /api/mini/subscribe/authorize   上报授权结果，服务器记录一次发送机会
//  4. 之后业务侧发站内信/审批待办时，服务器自动用掉这次机会推送
type AppMiniSubscribeController struct {
	beego.Controller
}

func (c *AppMiniSubscribeController) appClaims() (*jwtutil.Claims, error) {
	return identity.Claims(c.Ctx.Request.Header.Get("Authorization"), identity.EndApp, identity.EndBackend)
}

func (c *AppMiniSubscribeController) jsonErr(httpStatus, bizCode int, msg string) {
	c.Ctx.Output.SetStatus(httpStatus)
	c.Data["json"] = map[string]interface{}{"code": bizCode, "msg": msg}
	_ = c.ServeJSON()
}

func (c *AppMiniSubscribeController) ok(data interface{}, msg string) {
	if msg == "" {
		msg = "success"
	}
	c.Data["json"] = map[string]interface{}{"code": 200, "msg": msg, "data": data}
	_ = c.ServeJSON()
}

// Templates GET /api/mini/subscribe/templates
// 返回当前启用的订阅模板：小程序端拿 template_id 去调 requestSubscribeMessage
func (c *AppMiniSubscribeController) Templates() {
	claims, err := c.appClaims()
	if err != nil {
		code := identity.Status(err)
		c.jsonErr(code, code, err.Error())
		return
	}
	identityID := uint64(claims.UserID)

	apps, err := wechatmini.ListApps()
	if err != nil {
		c.jsonErr(500, 500, "读取小程序配置失败")
		return
	}
	list := make([]map[string]interface{}, 0)
	for _, app := range apps {
		if app.Enabled != 1 {
			continue
		}
		tpls, terr := wechatmini.ListTemplates(app.AppID)
		if terr != nil {
			continue
		}
		for _, tpl := range tpls {
			if tpl.Enabled != 1 || tpl.TemplateID == "" {
				continue
			}
			list = append(list, map[string]interface{}{
				"app_id":      app.AppID,
				"code":        tpl.Code,
				"title":       tpl.Title,
				"template_id": tpl.TemplateID,
				"page":        tpl.Page,
				"remain":      wechatmini.SubscribeRemain(identityID, app.AppID, tpl.TemplateID),
			})
		}
	}
	c.ok(map[string]interface{}{"list": list}, "获取成功")
}

// Authorize POST /api/mini/subscribe/authorize
// 上报用户授权结果：每授权一次，服务器记录一次可发送机会
func (c *AppMiniSubscribeController) Authorize() {
	claims, err := c.appClaims()
	if err != nil {
		code := identity.Status(err)
		c.jsonErr(code, code, err.Error())
		return
	}
	var p struct {
		TemplateIDs []string `json:"template_ids"`
	}
	raw, err := io.ReadAll(c.Ctx.Request.Body)
	if err != nil {
		c.jsonErr(400, 400, "参数错误")
		return
	}
	if err := json.Unmarshal(raw, &p); err != nil {
		c.jsonErr(400, 400, "参数错误")
		return
	}
	if len(p.TemplateIDs) == 0 {
		c.jsonErr(400, 400, "缺少 template_ids")
		return
	}
	identityID := uint64(claims.UserID)
	apps, err := wechatmini.ListApps()
	if err != nil {
		c.jsonErr(500, 500, "读取小程序配置失败")
		return
	}
	granted := 0
	for _, app := range apps {
		if app.Enabled != 1 {
			continue
		}
		// 只记录平台确实配置过的模板
		for _, tid := range p.TemplateIDs {
			tid = strings.TrimSpace(tid)
			if tid == "" {
				continue
			}
			tpls, terr := wechatmini.ListTemplates(app.AppID)
			if terr != nil {
				continue
			}
			matched := false
			for _, tpl := range tpls {
				if tpl.TemplateID == tid {
					matched = true
					break
				}
			}
			if !matched {
				continue
			}
			if gerr := wechatmini.GrantSubscribe(identityID, app.AppID, []string{tid}); gerr == nil {
				granted++
			}
		}
	}
	c.ok(map[string]interface{}{"granted": granted}, "已记录授权")
}

// TestNotice POST /api/mini/subscribe/test
// 给自己发一条测试订阅消息（用于验证模板配置是否正确）
func (c *AppMiniSubscribeController) TestNotice() {
	claims, err := c.appClaims()
	if err != nil {
		code := identity.Status(err)
		c.jsonErr(code, code, err.Error())
		return
	}
	var p struct {
		Title   string `json:"title"`
		Content string `json:"content"`
	}
	raw, _ := io.ReadAll(c.Ctx.Request.Body)
	_ = json.Unmarshal(raw, &p)
	title := strings.TrimSpace(p.Title)
	if title == "" {
		title = "测试提醒"
	}
	content := strings.TrimSpace(p.Content)
	if content == "" {
		content = "这是一条订阅消息测试，收到说明配置成功。"
	}

	identityID := uint64(claims.UserID)
	if wechatmini.MiniOpenIDByIdentity(identityID) == "" {
		c.jsonErr(400, 400, "当前账号未绑定小程序，请先用小程序登录")
		return
	}
	res := wechatmini.PushSubscribe(wechatmini.SceneNotice, identityID, map[string]string{
		"title":   title,
		"content": content,
	})
	if res.Sent > 0 {
		c.ok(map[string]interface{}{"sent": res.Sent}, "已发送")
		return
	}
	if len(res.Errors) > 0 {
		msg := res.Errors[0].Error()
		if hint := wechatmini.ExplainSubscribeError(res.Errors[0]); hint != "" {
			msg = hint
		}
		c.jsonErr(400, 400, msg)
		return
	}
	c.jsonErr(400, 400, "没有可用的订阅：模板未配置，或你还没授权订阅消息")
}