using UnityEngine;
using System.Collections;

namespace Wing.Utils
{
    public class FreeCamera : MonoBehaviour
    {
        //for rotate
        private float m_deltX = 0f;
        private float m_deltY = 0f;
        //for zoom
        private float m_distance = 10f;
        private float m_mSpeed = 5f;

        void Start()
        {
            //GetComponent<Camera>().transform.localPosition = new Vector3(0, m_distance, 0);
        }

        void Update()
        {
            //鼠标右键点下控制相机旋转;
            if (Input.GetMouseButton(1))
            {
                m_deltX += Input.GetAxis("Mouse X") * m_mSpeed;
                m_deltY -= Input.GetAxis("Mouse Y") * m_mSpeed;
                m_deltX = ClampAngle(m_deltX, -360, 360);
                m_deltY = ClampAngle(m_deltY, -70, 70);
                GetComponent<Camera>().transform.rotation = Quaternion.Euler(m_deltY, m_deltX, 0);
            }

            //鼠标中键点下场景缩放;
            if (Input.GetAxis("Mouse ScrollWheel") != 0)
            {
                //自由缩放方式;
                m_distance = Input.GetAxis("Mouse ScrollWheel") * 10f;
                GetComponent<Camera>().transform.localPosition = GetComponent<Camera>().transform.position + GetComponent<Camera>().transform.forward * m_distance;
            }
            //鼠标点击场景移动;
            if (Input.GetMouseButton(2))
            {
                var dx = -Input.GetAxis("Mouse X") * m_mSpeed * 0.1f;
                var dy = -Input.GetAxis("Mouse Y") * m_mSpeed * 0.1f;
                GetComponent<Camera>().transform.Translate(new Vector3(dx, dy));
            }

            //相机复位远点;
            if (Input.GetKey(KeyCode.Space))
            {
                m_distance = 10.0f;
                GetComponent<Camera>().transform.localPosition = new Vector3(0, m_distance, 0);
            }
        }

        //规划角度;
        float ClampAngle(float angle, float minAngle, float maxAgnle)
        {
            if (angle <= -360)
                angle += 360;
            if (angle >= 360)
                angle -= 360;

            return Mathf.Clamp(angle, minAngle, maxAgnle);
        }
    }
}