package handlers

import (
	"context"
	"net/http"
	"strconv"
	"strings"
	"time"

	"game-admin/internal/models"

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

func (h *GameHandler) ListModules(c *gin.Context) {
	var modules []models.Module
	err := h.db.NewSelect().
		Model(&modules).
		OrderExpr("id ASC").
		Scan(c)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, modules)
}

func (h *GameHandler) ListGameModules(c *gin.Context) {
	gameID, err := strconv.ParseInt(c.Param("id"), 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid game id"})
		return
	}

	exists, err := h.gameExists(c, gameID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}
	if !exists {
		c.JSON(http.StatusNotFound, gin.H{"error": "Game not found"})
		return
	}

	modulesByGame, err := h.loadModulesByGameIDs(c, []int64{gameID})
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, modulesByGame[gameID])
}

func (h *GameHandler) ConnectModule(c *gin.Context) {
	gameID, err := strconv.ParseInt(c.Param("id"), 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid game id"})
		return
	}

	var req models.ConnectGameModuleRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	exists, err := h.gameExists(c, gameID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}
	if !exists {
		c.JSON(http.StatusNotFound, gin.H{"error": "Game not found"})
		return
	}

	module := new(models.Module)
	err = h.db.NewSelect().
		Model(module).
		Where(`"key" = ?`, strings.TrimSpace(req.ModuleKey)).
		Scan(c)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Module not found"})
		return
	}

	gameModule := &models.GameModule{
		GameID:    gameID,
		ModuleID:  module.ID,
		CreatedAt: time.Now(),
	}
	_, err = h.db.NewInsert().Model(gameModule).Exec(c)
	if err != nil {
		c.JSON(http.StatusConflict, gin.H{"error": "Module already connected to game"})
		return
	}

	c.JSON(http.StatusCreated, module)
}

func (h *GameHandler) DisconnectModule(c *gin.Context) {
	gameID, err := strconv.ParseInt(c.Param("id"), 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid game id"})
		return
	}

	moduleKey := c.Param("module_key")
	module := new(models.Module)
	err = h.db.NewSelect().
		Model(module).
		Where(`"key" = ?`, moduleKey).
		Scan(c)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Module not found"})
		return
	}

	res, err := h.db.NewDelete().
		Model((*models.GameModule)(nil)).
		Where("game_id = ? AND module_id = ?", gameID, module.ID).
		Exec(c)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	if affected, _ := res.RowsAffected(); affected == 0 {
		c.JSON(http.StatusNotFound, gin.H{"error": "Module is not connected to game"})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Module disconnected"})
}

func (h *GameHandler) attachModulesToGames(c *gin.Context, games []models.Game) error {
	if len(games) == 0 {
		return nil
	}

	gameIDs := make([]int64, 0, len(games))
	for _, game := range games {
		gameIDs = append(gameIDs, game.ID)
	}

	modulesByGame, err := h.loadModulesByGameIDs(c, gameIDs)
	if err != nil {
		return err
	}

	for i := range games {
		games[i].Modules = modulesByGame[games[i].ID]
	}

	return nil
}

func (h *GameHandler) loadModulesByGameIDs(c *gin.Context, gameIDs []int64) (map[int64][]models.Module, error) {
	var gameModules []models.GameModule
	err := h.db.NewSelect().
		Model(&gameModules).
		Relation("Module").
		Where("gm.game_id IN (?)", bun.In(gameIDs)).
		OrderExpr("gm.id ASC").
		Scan(c)
	if err != nil {
		return nil, err
	}

	modulesByGame := make(map[int64][]models.Module, len(gameIDs))
	for _, gameID := range gameIDs {
		modulesByGame[gameID] = []models.Module{}
	}

	for _, gameModule := range gameModules {
		if gameModule.Module == nil {
			continue
		}
		modulesByGame[gameModule.GameID] = append(modulesByGame[gameModule.GameID], *gameModule.Module)
	}

	return modulesByGame, nil
}

func (h *GameHandler) gameHasModule(ctx context.Context, gameID int64, moduleKey string) (bool, error) {
	return h.db.NewSelect().
		Model((*models.GameModule)(nil)).
		Join("JOIN modules AS m ON m.id = gm.module_id").
		Where("gm.game_id = ?", gameID).
		Where(`m."key" = ?`, moduleKey).
		Exists(ctx)
}