/****************************************************
 *        VOLK      - NEW TRADE SKILL CODE          *
 *                                                  *
 *    Not that there's anything wrong with the old  *
 *    code, but I wanted to recreate some trade     *
 *    skills that have been in my head for ages,    *
 *    especially a more realistic type of mining w/ *
 *    lots of extra content involved. Like all my   *
 *    code, this is completely open source under    *
 *    GPL - GNU public license, originally written  *
 *    for Classic 6 Dragons MUD in Jan 2016.        *
 *                                                  *
 ****************************************************/

/* do_mine is used to dig an exit, creating a new room if one doesn't already exist there (and a new mine if the
 * player doesn't already own a mine!) or widening an existing room (if the player can't enter due to recent save-ins etc).
 * It can be used with a direction or on its own targetting the current room.
 * Rooms are always 10ft feep but start 5x5 ft wide, and must be widened 1x1 ft at a time up to a maximum of 15x15 ft wide.
 * To create an exit, the room must be at least 2x2 per exit (ie a new 5x5 room, with one exit already existing from above,
 * can support one additional exit before widening is required). While digging has a small chance to recover ores/gems, widening
 * has a larger chance and will allow for more players in the room, more objects etc.
 * Rooms have a rocktype, an integrity and a condition. Condition decays, and lower integrity decays quicker. Stronger rocktypes
 * (ie iron ore vs granite vs shale or sand) and depth also contribute to integrity, as well as various supports and shoring devices
 * installed by the player. 
 *
 * Different shorings have different integrity and conditions. The integrity will add to the rooms integrity, causing slower
 * condition decay, and the decay will instead affect the shoring (ie when object->condition = 0, the object will vanish, and
 * further decay will affect the room->condition). Shoring requires 5x5 ft rooms to install (so a 15x15 room can have 3 shorings),
 * but can also be repaired with the appropriate materials. Shoring can be removed by the player, returning some materials depending
 * on condition.
 *
 * When a room condition reaches 0, it 'collapses'. Any items are lost, and mobs or players in the room killed. Exits remain, but 
 * room size will reduce to 1x1ft (can't be entered until dug out again). Once dug to a minimum of 5x5, condition will be reset to
 * 50%. In addition, if there are exits below, falling rocks are spawned. 
 *
 * Rooms also have random resource and worth values, which determine what items are rewarded when the room is mined in. Worth value
 * is fixed, but resource value will deplete. This is a current/maximum type arrangement, with the resource value replenishing slowly
 * over time (to a maximum of 20% of worth). Worth is usually a function of rocktype and depth, with deeper rooms worth more.
 * The rooms are all linked forever and exits can't be removed - however, a player can purchase (at a great expense) and explosive
 * to destroy all rooms below the depth of the room they are currently in.
 *
 * All mine data is saved in mines.dat, including creator, all room information including obj and mobs loaded, and exits. These are
 * not actually rooms but are a separate entitiy completely. They will load on startup and anyone may access them.
 * As well as integrity issues, at greater depths the player will encounter random mob spawns, traps, random 'room' spawns (a
 * prebuild 'lair' area), and possible mine flooding. The player will need to install ladders to move up and down mine shafts
 * without fly, but can float down without damage. Any objects in the room (including ladders) will take up 1x1ft of space, leaving
 * less room for shoring. The room descs are all generated according to the room data. 
 *
 * Evil things - mining creates dust and a player can get a mining sickness debuff. Also, mining creates an abundance of crap
 * (gravel, sand, dirt, limestone, dolomite etc) which is not only really heavy, but because of the one item = 1x1ft of space
 * rule, can't just be dropped on the floor (unless the player wants to skip shoring, which is a bad idea). So given the limited
 * amount of inventory weight/space, the player will need to cart his/her waste to the surface to get rid of it. Gas release/
 * explosion - on expanding a room, player can tap into a pocket of gas, which will temporarily stun and can possibly ignite.
 * Mine is also dark, will require adequate lighting.
 */

/* If pickaxe breaks and both parts are in inventory (ie head and handle), it can be repaired. Sometimes either or both
 * will break into scraps. A stronger handle and a higher level will reduce the chance for the pickaxe to break. A
 * stronger head (requires a minimum level) will mine faster (less waitstates between mines) */

/* Player can use the 'repair' command to repair any shoring in the room. Can write a call to this method from repair. */

/* Used to install shoring and ladders, but eventually I want to allow players to create furniture for their player-owned houses 
 * and install it themselves, or have someone install it for them. Also eventually may allow player to install water pumps
 * and operate them to empty mine of water, some sort of lighting, ventilation to control mining sickness and gas explosions etc
 */