using RPGCore.Stats.ObjectModules.StatsObjectModule.Events;
using UnityEngine;

namespace RPGCore.Stats.ObjectModules.StatsObjectModule
{
    /// <summary>
    /// <b>You should never instantiate this by yourself!</b>
    /// Instantiated automatically by <see cref="StatsModule"/> for every available <see cref="StatResourceDefinitionSO"/>.
    /// </summary>
    public sealed class StatResource
    {
        public StatResourceDefinitionSO definition { get; internal set; }
        public StatValue statValue { get; internal set; }
        
        /// <summary>
        /// This value represent current resource of this stat. Always between <see cref="StatValue.baseValue"/> and <see cref="StatValue.value"/>
        /// </summary>
        public int resource { get; private set; }

        internal StatResource(StatResourceDefinitionSO definition, int defaultValue, StatValue statValue)
        {
            this.definition = definition;
            resource = defaultValue;
            this.statValue = statValue;
        }

        /// <summary>
        /// Changes (or simpler - uses) <see cref="resource"/> of this stat value by given amount.
        /// It just calls <see cref="SetResource(int)"/> with: <see cref="resource"/> + <see cref="amount"/>
        /// </summary>
        /// <param name="amount">Amount that will be added or subtracted from <see cref="resource"/></param>
        public void ChangeResource(int amount)
        {
            SetResource(resource + amount);
        }

        /// <summary>
        /// Sets <see cref="resource"/> to given amount. Amount will be clamped between ZERO and <see cref="StatValue.value"/>.
        /// </summary>
        /// <param name="amount">New amount</param>
        public void SetResource(int amount)
        {
            var old = resource;
            resource = Mathf.Clamp(amount, 0, statValue.value);
            statValue.obj.events.Invoke(new StatResourceChangeEvent
            {
                delta = resource - old,
                after = resource,
                before = old,
                resourceDefinition = definition,
                target = statValue.obj
            });
        }

        /// <summary>
        /// Sets <see cref="resource"/> to given percentage. Percentage will be clamped between ZERO and ONE.
        /// </summary>
        /// <param name="percentage">New percentage</param>
        public void SetResource(float percentage)
        {
            SetResource(Mathf.CeilToInt(Mathf.Clamp01(percentage) * statValue.value));
        }
    }
}