package handler

import (
	"encoding/json"
	"fmt"
	"log/slog"
	"net/http"
	"strconv"
	"strings"

	"aiaa-notification-service/internal/adapter"
	"aiaa-notification-service/internal/cache"
	"aiaa-notification-service/internal/model"
	"aiaa-notification-service/internal/safew"
	"aiaa-notification-service/internal/store"

	"github.com/gin-gonic/gin"
)

type ChannelHandler struct {
	store *store.Store
	cache *cache.Cache
	chats *safew.Watcher
}

func NewChannelHandler(s *store.Store, c *cache.Cache, w *safew.Watcher) *ChannelHandler {
	return &ChannelHandler{store: s, cache: c, chats: w}
}

type createChannelReq struct {
	Name   string          `json:"name"   binding:"required"`
	Type   string          `json:"type"   binding:"required"`
	Config json.RawMessage `json:"config" binding:"required"`
	Status int             `json:"status"`
}

func (h *ChannelHandler) Create(c *gin.Context) {
	var req createChannelReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	if req.Status == 0 {
		req.Status = 1
	}
	raw := json.RawMessage(req.Config)
	ch := &model.Channel{Name: req.Name, Type: req.Type, Config: &raw, Status: req.Status}
	if err := h.store.CreateChannel(c.Request.Context(), ch); err != nil {
		c.JSON(http.StatusConflict, gin.H{"error": err.Error()})
		return
	}
	c.JSON(http.StatusCreated, ch)
}

func (h *ChannelHandler) List(c *gin.Context) {
	var page store.PageFilter
	if err := c.ShouldBindQuery(&page); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	page.Normalize()

	channels, total, err := h.store.ListChannels(c.Request.Context(), page)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}
	c.JSON(http.StatusOK, gin.H{"data": channels, "total": total, "page": page.Page})
}

func (h *ChannelHandler) Get(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	ch, err := h.store.GetChannel(c.Request.Context(), id)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "channel not found"})
		return
	}
	c.JSON(http.StatusOK, ch)
}

func (h *ChannelHandler) Update(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	var req createChannelReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	raw := json.RawMessage(req.Config)
	ch := &model.Channel{Name: req.Name, Type: req.Type, Config: &raw, Status: req.Status}
	if err := h.store.UpdateChannel(c.Request.Context(), id, ch); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}
	c.JSON(http.StatusOK, gin.H{"ok": true})
}

func (h *ChannelHandler) Delete(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	if err := h.store.DeleteChannel(c.Request.Context(), id); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}
	c.JSON(http.StatusOK, gin.H{"ok": true})
}

type listSafewChatsReq struct {
	Token string `json:"token"`
	Q     string `json:"q"`
}

func (h *ChannelHandler) ListSafewChats(c *gin.Context) {
	var req listSafewChatsReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	h.respondSafewChats(c, strings.TrimSpace(req.Token), req.Q)
}

func (h *ChannelHandler) ListChannelSafewChats(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	ch, err := h.store.GetChannel(c.Request.Context(), id)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "channel not found"})
		return
	}
	token, err := safewTokenFromChannel(ch)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	h.respondSafewChats(c, token, c.Query("q"))
}

func (h *ChannelHandler) respondSafewChats(c *gin.Context, token, q string) {
	if token == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "safew token is required"})
		return
	}
	if h.chats == nil {
		c.JSON(http.StatusServiceUnavailable, gin.H{"error": "safew chat list unavailable"})
		return
	}
	h.chats.Ensure(token)
	if err := h.chats.Refresh(c.Request.Context(), token); err != nil {
		if _, ok := err.(*adapter.SafewAuthError); ok {
			c.JSON(http.StatusUnauthorized, gin.H{"error": err.Error()})
			return
		}
		slog.Warn("safew refresh", "error", err)
	}
	list, err := h.chats.List(c.Request.Context(), token, q)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}
	if list == nil {
		list = []adapter.SafewChat{}
	}
	c.JSON(http.StatusOK, gin.H{"data": list, "total": len(list)})
}

func safewTokenFromChannel(ch *model.Channel) (string, error) {
	if ch.Type != "safew" {
		return "", fmt.Errorf("channel is not safew")
	}
	if ch.Config == nil {
		return "", fmt.Errorf("safew token is required")
	}
	var cfg struct {
		Token string `json:"token"`
	}
	if err := json.Unmarshal(*ch.Config, &cfg); err != nil {
		return "", fmt.Errorf("safew token is required")
	}
	token := strings.TrimSpace(cfg.Token)
	if token == "" {
		return "", fmt.Errorf("safew token is required")
	}
	return token, nil
}