package main

import (
	"log"
	"net/http"

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

func main() {
	db, err := InitDB()
	if err != nil {
		log.Fatalf("failed to initialize database: %v", err)
	}
	DB = db

	router := gin.Default()

	router.GET("/ping", func(c *gin.Context) {
		c.JSON(200, gin.H{
			"message": "pong",
		})
	})

	router.GET("/db-check", func(c *gin.Context) {
		if err := DB.Ping(); err != nil {
			c.JSON(http.StatusServiceUnavailable, gin.H{"status": "unreachable", "error": err.Error()})
			return
		}
		c.JSON(http.StatusOK, gin.H{"status": "ok"})
	})

	// User routes
	router.POST("/users", createUserHandler)
	router.GET("/users/:id", getUserHandler)
	router.PUT("/users/:id", updateUserHandler)
	router.DELETE("/users/:id", deleteUserHandler)

	// Object routes
	router.POST("/objects", createObjectHandler)
	router.GET("/objects/:id", getObjectHandler)
	router.GET("/users/:id/objects", getObjectsByUserHandler)
	router.PUT("/objects/:id", updateObjectHandler)
	router.DELETE("/objects/:id", deleteObjectHandler)

	router.Run() // listens on 0.0.0.0:8080 by default
}

// createUserRequest is the expected body for POST /users.
type createUserRequest struct {
	UserID       string `json:"userId" binding:"required"`
	RootObjectID string `json:"rootObjectId" binding:"required"`
}

func createUserHandler(c *gin.Context) {
	var req createUserRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := CreateUser(req.UserID, req.RootObjectID); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusCreated, gin.H{"status": "created"})
}

func getUserHandler(c *gin.Context) {
	id := c.Param("id")
	user, err := GetUser(id)
	if err != nil {
		if err.Error() == "user not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, user)
}

// updateUserRequest is the expected body for PUT /users/:id.
type updateUserRequest struct {
	RootObjectID string `json:"rootObjectId" binding:"required"`
}

func updateUserHandler(c *gin.Context) {
	id := c.Param("id")
	var req updateUserRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := UpdateUser(id, req.RootObjectID); err != nil {
		if err.Error() == "user not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"status": "updated"})
}

func deleteUserHandler(c *gin.Context) {
	id := c.Param("id")
	if err := DeleteUser(id); err != nil {
		if err.Error() == "user not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"status": "deleted"})
}

// createObjectRequest is the expected body for POST /objects.
type createObjectRequest struct {
	ObjectID   string `json:"objectId" binding:"required"`
	UserID     string `json:"userId" binding:"required"`
	ObjectData string `json:"objectData" binding:"required"`
}

func createObjectHandler(c *gin.Context) {
	var req createObjectRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := CreateObject(req.ObjectID, req.UserID, req.ObjectData); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusCreated, gin.H{"status": "created"})
}

func getObjectHandler(c *gin.Context) {
	id := c.Param("id")
	obj, err := GetObject(id)
	if err != nil {
		if err.Error() == "object not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, obj)
}

func getObjectsByUserHandler(c *gin.Context) {
	id := c.Param("id")
	objects, err := GetObjectsByUser(id)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, objects)
}

// updateObjectRequest is the expected body for PUT /objects/:id.
type updateObjectRequest struct {
	ObjectData string `json:"objectData" binding:"required"`
}

func updateObjectHandler(c *gin.Context) {
	id := c.Param("id")
	var req updateObjectRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := UpdateObject(id, req.ObjectData); err != nil {
		if err.Error() == "object not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"status": "updated"})
}

func deleteObjectHandler(c *gin.Context) {
	id := c.Param("id")
	if err := DeleteObject(id); err != nil {
		if err.Error() == "object not found" {
			c.JSON(http.StatusNotFound, gin.H{"error": err.Error()})
			return
		}
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"status": "deleted"})
}