package api

import (
	"encoding/json"
	"log"
	"net/http"
	"strconv"

	authdiscord "example.com/auth/discord"
	configserver "example.com/config/server"
	character "example.com/database/character"
	customization "example.com/database/customization"
	function "example.com/database/function"
	functionset "example.com/database/functionset"
	functiontag "example.com/database/functiontag"
	group "example.com/database/group"
	inventoryslot "example.com/database/inventoryslot"
	item "example.com/database/item"
	itemtag "example.com/database/itemtag"
	person "example.com/database/person"
	role "example.com/database/role"
	schematic "example.com/database/schematic"
	tier "example.com/database/tier"
	user "example.com/database/user"

	"github.com/gin-gonic/gin"
	"github.com/xyproto/randomstring"
	"golang.org/x/oauth2"
	"gorm.io/gorm"
)

var GlobalDatabase *gorm.DB
var GlobalConfig configserver.AppConfig
var GlobalOAuth *oauth2.Config

// Private Functions

func updateUser(context *gin.Context, discordUser authdiscord.DiscordUser, oauthTokenJSON string) {
	err := user.Update(
		GlobalDatabase,
		discordUser.Id,
		discordUser.Global_Name,
		discordUser.Username,
		discordUser.Avatar,
		discordUser.Avatar_Decoration_Data.Asset,
		oauthTokenJSON,
		true,
	)
	if err != nil {
		log.Println(err)
		context.AbortWithStatus(http.StatusInternalServerError)
	}

}

func createUser(context *gin.Context, discordUser authdiscord.DiscordUser, oauthTokenJSON string) {
	err := user.Create(
		GlobalDatabase,
		discordUser.Id,
		discordUser.Global_Name,
		discordUser.Username,
		discordUser.Avatar,
		discordUser.Avatar_Decoration_Data.Asset,
		oauthTokenJSON,
		true,
	)
	if err != nil {
		log.Println(err)
		context.AbortWithStatus(http.StatusInternalServerError)
	}
}

func checkAuthentication(context *gin.Context) *oauth2.Token {
	oauthTokenJSON, err := context.Cookie("discord-oauthtoken")
	if err == nil {
		var oauthToken *oauth2.Token
		err := json.Unmarshal([]byte(oauthTokenJSON), &oauthToken)
		if err == nil {
			if oauthToken.Valid() {
				if (*user.Get(GlobalDatabase, []string{oauthTokenJSON}))[0].LoggedIn {
					return oauthToken
				}
			}
		}
	}
	return nil
}

func objectIDStringsToInts(context *gin.Context, objectIDs []string) *[]int {
	var objectIDInts []int
	for _, objectID := range objectIDs {
		objectIDInt, err := strconv.Atoi(objectID)
		if err != nil {
			objectIDInts = append(objectIDInts, objectIDInt)
		} else {
			context.AbortWithStatus(http.StatusBadRequest)
		}
	}
	return &objectIDInts
}

// Authentication Workflow

func AuthCallback(context *gin.Context) {
	// Discord OAuth library requires this.
	oauthState := randomstring.CookieFriendlyString(32)
	context.Set("state", oauthState)
	// Get the OAuth token.
	oauthToken, err := GlobalOAuth.Exchange(context.Request.Context(), context.Query("code"))
	if err != nil {
		context.Redirect(http.StatusInternalServerError, GlobalConfig.GetFrontendRootDomain())
		return
	}
	// Get the current discord user info.
	var currentDiscordUser authdiscord.DiscordUser
	result := currentDiscordUser.Get(context, oauthToken, GlobalOAuth)
	if result != "" {
		context.Redirect(http.StatusInternalServerError, GlobalConfig.GetFrontendRootDomain())
		return
	} else {
		var currentUser user.User
		// Parse object to string so we can save as a cookie.
		oauthTokenJSON, _ := json.Marshal(oauthToken)
		// Either create or update the user in the database
		if currentUser.Get(GlobalDatabase, currentDiscordUser.Id) == nil {
			if currentUser.LoggedIn {
				oauthTokenJSON = []byte(currentUser.LoginToken)
			}
			updateUser(context, currentDiscordUser, string(oauthTokenJSON))
		} else {
			createUser(context, currentDiscordUser, string(oauthTokenJSON))
		}
		// Save the resulting oauthTokenJSON as a cookie.
		context.SetCookie("discord-oauthtoken", string(oauthTokenJSON), 0, "", GlobalConfig.API.Domain, false, false)

	}
	// Redirect to the dashboard once logged in.
	context.Redirect(http.StatusTemporaryRedirect, GlobalConfig.GetFrontendRootDomain()+"/dashboard")
}

func AuthLoginRedirect(context *gin.Context) {
	context.Redirect(http.StatusTemporaryRedirect, GlobalOAuth.AuthCodeURL(context.GetString("state")))
}

func AuthLogoutRedirect(context *gin.Context) {
	oauthTokenJSON, err := context.Cookie("discord-oauthtoken")
	if err == nil {
		user.Logout(GlobalDatabase, oauthTokenJSON)
		context.SetCookie("discord-oauthtoken", "", -1, "", GlobalConfig.API.Domain, false, true)
	} else {
		log.Println(err)
	}
	log.Println(GlobalConfig.GetFrontendRootDomain())
	context.Redirect(http.StatusTemporaryRedirect, GlobalConfig.GetFrontendRootDomain())
}

// Create Endpoints (POST)

func CreateObject(context *gin.Context) {
	if checkAuthentication(context) != nil {
		_, idOk := context.GetQuery("id")
		if idOk {
			var result error
			switch objectType := context.Param("object"); objectType {
			case "user":
				//
			case "person":
				//
			case "group":
				result = group.Create(GlobalDatabase, context)
			case "character":
				//
			case "role":
				//
			case "tier":
				//
			case "function-set":
				//
			case "function":
				result = function.Create(GlobalDatabase, context)
			case "function-tag":
				result = functiontag.Create(GlobalDatabase, context)
			case "inventory-slot":
				//
			case "item":
				//
			case "item-tag":
				//
			case "customization":
				//
			case "schematic":
				//
			}
			if result != nil {
				context.JSON(http.StatusBadRequest, gin.H{
					"message": result.Error(),
				})
			} else {
				context.Status(http.StatusOK)
			}
		} else {
			context.AbortWithStatus(http.StatusBadRequest)
		}
	} else {
		context.AbortWithStatus(http.StatusUnauthorized)
	}
}

// Update Endpoints (PUT)

func UpdateObject(context *gin.Context) {
	if checkAuthentication(context) != nil {
		_, idOk := context.GetQuery("id")
		if idOk {
			var result error
			switch objectType := context.Param("object"); objectType {
			case "user":
				//
			case "person":
				//
			case "group":
				// result = group.Create(GlobalDatabase, context)
			case "character":
				//
			case "role":
				//
			case "tier":
				//
			case "function-set":
				//
			case "function":
				result = function.Update(GlobalDatabase, context)
			case "function-tag":
				// result = functiontag.Create(GlobalDatabase, objectID)
			case "inventory-slot":
				//
			case "item":
				//
			case "item-tag":
				//
			case "customization":
				//
			case "schematic":
				//
			}
			if result != nil {
				context.JSON(http.StatusBadRequest, gin.H{
					"message": result.Error(),
				})
			} else {
				context.Status(http.StatusOK)
			}
		} else {
			context.AbortWithStatus(http.StatusBadRequest)
		}
	} else {
		context.AbortWithStatus(http.StatusUnauthorized)
	}
}

// Read Endpoints (GET)

func GetDiscordUser(context *gin.Context) {
	oauthToken := checkAuthentication(context)
	if oauthToken != nil {
		var discordUser authdiscord.DiscordUser
		result := discordUser.Get(context, oauthToken, GlobalOAuth)
		if result != "" {
			log.Println(result)
			log.Println("Assuming the Discord OAuth Key has expired.")
			context.Redirect(http.StatusUnauthorized, GlobalConfig.GetFrontendRootDomain()+"/logout")
		} else {
			if (*user.Get(GlobalDatabase, []string{discordUser.Id}))[0].LoggedIn {
				context.JSON(http.StatusOK, discordUser)
			} else {
				context.Redirect(http.StatusTemporaryRedirect, GlobalConfig.GetFrontendRootDomain()+"/logout")
			}
		}
	}
}

func GetUserLoggedIn(context *gin.Context) {
	context.JSON(http.StatusOK, gin.H{
		"message": (checkAuthentication(context) != nil),
	})
}

func GetObjects(context *gin.Context) {
	objectIDs, idOk := context.GetQueryArray("id")
	if idOk {
		switch objectType := context.Param("object"); objectType {
		case "user":
			context.JSON(http.StatusOK, gin.H{
				"user": user.Get(GlobalDatabase, objectIDs)})
		case "persons":
			context.JSON(http.StatusOK, gin.H{
				"persons": person.Get(GlobalDatabase, objectIDs),
			})
		case "groups":
			context.JSON(http.StatusOK, gin.H{
				"groups": group.Get(GlobalDatabase, objectIDs),
			})
		case "characters":
			context.JSON(http.StatusOK, gin.H{
				"characters": character.Get(GlobalDatabase, objectIDs),
			})
		case "roles":
			context.JSON(http.StatusOK, gin.H{
				"roles": role.Get(GlobalDatabase, objectIDs),
			})
		case "tiers":
			objectIDInts := objectIDStringsToInts(context, objectIDs)
			context.JSON(http.StatusOK, gin.H{
				"tiers": tier.Get(GlobalDatabase, *objectIDInts),
			})
		case "function-sets":
			objectIDInts := objectIDStringsToInts(context, objectIDs)
			context.JSON(http.StatusOK, gin.H{
				"function_sets": functionset.Get(GlobalDatabase, *objectIDInts),
			})
		case "functions":
			context.JSON(http.StatusOK, gin.H{
				"functions": function.Get(GlobalDatabase, objectIDs),
			})
		case "function-tags":
			context.JSON(http.StatusOK, gin.H{
				"function_tags": functiontag.Get(GlobalDatabase, objectIDs),
			})
		case "inventory-slot":
			objectIDInts := objectIDStringsToInts(context, objectIDs)
			context.JSON(http.StatusOK, gin.H{
				"inventory_slot": inventoryslot.Get(GlobalDatabase, *objectIDInts),
			})
		case "items":
			context.JSON(http.StatusOK, gin.H{
				"items": item.Get(GlobalDatabase, objectIDs),
			})
		case "item-tags":
			context.JSON(http.StatusOK, gin.H{
				"item_tags": itemtag.Get(GlobalDatabase, objectIDs),
			})
		case "customizations":
			context.JSON(http.StatusOK, gin.H{
				"customizations": customization.Get(GlobalDatabase, objectIDs),
			})
		case "schematics":
			objectIDInts := objectIDStringsToInts(context, objectIDs)
			context.JSON(http.StatusOK, gin.H{
				"schematics": schematic.Get(GlobalDatabase, *objectIDInts),
			})
		}
	} else {
		context.Status(http.StatusBadRequest)
	}
}

func GetAllObjects(context *gin.Context) {
	switch objectType := context.Param("object"); objectType {
	case "persons":
		context.JSON(http.StatusOK, gin.H{
			"persons": person.GetAll(GlobalDatabase),
		})
	case "groups":
		context.JSON(http.StatusOK, gin.H{
			"groups": group.GetAll(GlobalDatabase),
		})
	case "characters":
		context.JSON(http.StatusOK, gin.H{
			"characters": character.GetAll(GlobalDatabase),
		})
	case "roles":
		context.JSON(http.StatusOK, gin.H{
			"roles": role.GetAll(GlobalDatabase),
		})
	case "tiers":
		context.JSON(http.StatusOK, gin.H{
			"tiers": tier.GetAll(GlobalDatabase),
		})
	case "function-sets":
		context.JSON(http.StatusOK, gin.H{
			"function_sets": functionset.GetAll(GlobalDatabase),
		})
	case "functions":
		context.JSON(http.StatusOK, gin.H{
			"functions": function.GetAll(GlobalDatabase),
		})
	case "function-tags":
		context.JSON(http.StatusOK, gin.H{
			"function_tags": functiontag.GetAll(GlobalDatabase),
		})
	case "inventory-slot":
		context.JSON(http.StatusOK, gin.H{
			"inventory_slot": inventoryslot.GetAll(GlobalDatabase),
		})
	case "items":
		context.JSON(http.StatusOK, gin.H{
			"items": item.GetAll(GlobalDatabase),
		})
	case "item-tags":
		context.JSON(http.StatusOK, gin.H{
			"item_tags": itemtag.GetAll(GlobalDatabase),
		})
	case "customizations":
		context.JSON(http.StatusOK, gin.H{
			"customizations": customization.GetAll(GlobalDatabase),
		})
	case "schematics":
		context.JSON(http.StatusOK, gin.H{
			"schematics": schematic.GetAll(GlobalDatabase),
		})
	}
}

// Delete Endpoints (DELETE)

func DeleteObject(context *gin.Context) {
	if checkAuthentication(context) != nil {
		objectIDs, idOk := context.GetQueryArray("id")
		if idOk {
			var result error
			switch objectType := context.Param("object"); objectType {
			case "user":
				//
			case "person":
				//
			case "group":
				// result = group.Create(GlobalDatabase, context)
			case "character":
				//
			case "role":
				//
			case "tier":
				//
			case "function-set":
				//
			case "function":
				result = function.Delete(GlobalDatabase, objectIDs)
			case "function-tag":
				// result = functiontag.Create(GlobalDatabase, objectID)
			case "inventory-slot":
				//
			case "item":
				//
			case "item-tag":
				//
			case "customization":
				//
			case "schematic":
				//
			}
			if result != nil {
				context.JSON(http.StatusBadRequest, gin.H{
					"message": result.Error(),
				})
			} else {
				context.Status(http.StatusOK)
			}
		} else {
			context.AbortWithStatus(http.StatusBadRequest)
		}
	} else {
		context.AbortWithStatus(http.StatusUnauthorized)
	}
}