// forceequip plugin
// Moves local items from the ground into a unit's inventory
#include <iostream>
#include <iomanip>
#include <sstream>
#include <climits>
#include <vector>
#include <string>
#include <algorithm>
#include <set>
using namespace std;

#include "Core.h"
#include "Console.h"
#include "Export.h"
#include "PluginManager.h"
#include "modules/Maps.h"
#include "modules/Gui.h"
#include "modules/Items.h"
#include "modules/Materials.h"
#include "modules/MapCache.h"
#include "DataDefs.h"
#include "df/item.h"
#include "df/itemdef.h"
#include "df/world.h"
#include "df/general_ref.h"
#include "df/unit.h"
#include "df/body_part_raw.h"
#include "MiscUtils.h"
#include "df/unit_inventory_item.h"
#include "df/body_part_raw_flags.h"
#include "df/creature_raw.h"
#include "df/caste_raw.h"
#include "df/body_detail_plan.h"
#include "df/body_template.h"
#include "df/body_part_template.h"
#include "df/unit_soul.h"
#include "df/unit_skill.h"
#include "df/general_ref.h"
#include "df/caste_raw.h"

#include "DFHack.h"

using namespace DFHack;
using namespace df::enums;

using MapExtras::Block;
using MapExtras::MapCache;

DFHACK_PLUGIN("forceequip");
REQUIRE_GLOBAL(world);

const int const_GloveRightHandedness = 1;
const int const_GloveLeftHandedness = 2;

command_result df_forceequip(color_ostream &out, vector <string> & parameters);

DFhackCExport command_result plugin_init ( color_ostream &out, vector <PluginCommand> &commands)
{
    commands.push_back(PluginCommand(
        "forceequip",
        "Move items into a unit's inventory.",
        df_forceequip));

    return CR_OK;
}

DFhackCExport command_result plugin_shutdown ( color_ostream &out )
{
    return CR_OK;
}

static bool moveToInventory(MapExtras::MapCache &mc, df::item *item, df::unit *unit, df::body_part_raw * targetBodyPart, bool ignoreRestrictions, int multiEquipLimit, bool verbose)
{
    // Step 1: Check for anti-requisite conditions
    df::unit * itemOwner = Items::getOwner(item);
    if (ignoreRestrictions)
    {
        // If the ignoreRestrictions cmdline switch was specified, then skip all of the normal preventative rules
        if (verbose) { Core::print("Skipping integrity checks...\n"); }
    }
    else if(!item->isClothing() && !item->isArmorNotClothing())
    {
        if (verbose) { Core::printerr("Item %d is not clothing or armor; it cannot be equipped.  Please choose a different item (or use the Ignore option if you really want to equip an inappropriate item).\n", item->id); }
        return false;
    }
    else if (item->getType() != df::enums::item_type::GLOVES &&
        item->getType() != df::enums::item_type::HELM &&
        item->getType() != df::enums::item_type::ARMOR &&
        item->getType() != df::enums::item_type::PANTS &&
        item->getType() != df::enums::item_type::SHOES &&
        !targetBodyPart)
    {
        if (verbose) { Core::printerr("Item %d is of an unrecognized type; it cannot be equipped (because the module wouldn't know where to put it).\n", item->id); }
        return false;
    }
    else if (itemOwner && itemOwner->id != unit->id)
    {
        if (verbose) { Core::printerr("Item %d is owned by someone else.  Equipping it on this unit is not recommended.  Please use DFHack's Confiscate plugin, choose a different item, or use the Ignore option to proceed in spite of this warning.\n", item->id); }
        return false;
    }
    else if (item->flags.bits.in_inventory)
    {
        if (verbose) { Core::printerr("Item %d is already in a unit's inventory.  Direct inventory transfers are not recommended; please move the item to the ground first (or use the Ignore option).\n", item->id); }
        return false;
    }
    else if (item->flags.bits.in_job)
    {
        if (verbose) { Core::printerr("Item %d is reserved for use in a queued job.  Equipping it is not recommended, as this might interfere with the completion of vital jobs.  Use the Ignore option to ignore this warning.\n", item->id); }
        return false;
    }

    // ASSERT: anti-requisite conditions have been satisfied (or disregarded)


    // Step 2: Try to find a bodypart which is eligible to receive equipment AND which is appropriate for the specified item
    df::body_part_raw * confirmedBodyPart = NULL;
    size_t bpIndex;
    for(bpIndex = 0; bpIndex < unit->body.body_plan->body_parts.size(); bpIndex++)
    {
        df::body_part_raw * currPart = unit->body.body_plan->body_parts[bpIndex];

        // Short-circuit the search process if a BP was specified in the function call
        // Note: this causes a bit of inefficient busy-looping, but the search space is tiny (<100) and we NEED to get the correct bpIndex value in order to perform inventory manipulations
        if (!targetBodyPart)
        {
            // The function call did not specify any particular body part; proceed with normal iteration and evaluation of BP eligibility
        }
        else if (currPart == targetBodyPart)
        {
            // A specific body part was included in the function call, and we've found it; proceed with the normal BP evaluation (suitability, emptiness, etc)
        }
        else if (bpIndex < unit->body.body_plan->body_parts.size())
        {
            // The current body part is not the one that was specified in the function call, but we can keep searching
            if (verbose) { Core::printerr("Found bodypart %s; not a match; continuing search.\n", currPart->token.c_str()); }
            continue;
        }
        else
        {
            // The specified body part has not been found, and we've reached the end of the list.  Report failure.
            if (verbose) { Core::printerr("The specified body part (%s) does not belong to the chosen unit.  Please double-check to ensure that your spelling is correct, and that you have not chosen a dismembered bodypart.\n",targetBodyPart->token.c_str()); }
            return false;
        }

        if (verbose) { Core::print("Inspecting bodypart %s.\n", currPart->token.c_str()); }

        // Inspect the current bodypart
        if (item->getType() == df::enums::item_type::GLOVES && currPart->flags.is_set(df::body_part_raw_flags::GRASP) &&
            ((item->getGloveHandedness() == const_GloveLeftHandedness && currPart->flags.is_set(df::body_part_raw_flags::LEFT)) ||
            (item->getGloveHandedness() == const_GloveRightHandedness && currPart->flags.is_set(df::body_part_raw_flags::RIGHT))))
        {
            if (verbose) { Core::print("Hand found (%s)...", currPart->token.c_str()); }
        }
        else if (item->getType() == df::enums::item_type::HELM && currPart->flags.is_set(df::body_part_raw_flags::HEAD))
        {
            if (verbose) { Core::print("Head found (%s)...", currPart->token.c_str()); }
        }
        else if (item->getType() == df::enums::item_type::ARMOR && currPart->flags.is_set(df::body_part_raw_flags::UPPERBODY))
        {
            if (verbose) { Core::print("Upper body found (%s)...", currPart->token.c_str()); }
        }
        else if (item->getType() == df::enums::item_type::PANTS && currPart->flags.is_set(df::body_part_raw_flags::LOWERBODY))
        {
            if (verbose) { Core::print("Lower body found (%s)...", currPart->token.c_str()); }
        }
        else if (item->getType() == df::enums::item_type::SHOES && currPart->flags.is_set(df::body_part_raw_flags::STANCE))
        {
            if (verbose) { Core::print("Foot found (%s)...", currPart->token.c_str()); }
        }
        else if (targetBodyPart && ignoreRestrictions)
        {
            // The BP in question would normally be considered ineligible for equipment.  But since it was deliberately specified by the user, we'll proceed anyways.
            if (verbose) { Core::print("Non-standard bodypart found (%s)...", targetBodyPart->token.c_str()); }
        }
        else if (targetBodyPart)
        {
            // The BP in question is not eligible for equipment and the ignore flag was not specified.  Report failure.
            if (verbose) { Core::printerr("Non-standard bodypart found, but it is ineligible for standard equipment.  Use the Ignore flag to override this warning.\n"); }
            return false;
        }
        else
        {
            if (verbose) { Core::print("Skipping ineligible bodypart.\n"); }
            // This body part is not eligible for the equipment in question; skip it
            continue;
        }

        // ASSERT: The current body part is able to support the specified equipment (or the test has been overridden).  Check whether it is currently empty/available.

        if (multiEquipLimit == INT_MAX)
        {
            // Note: this loop/check is skipped if the MultiEquip option is specified; we'll simply add the item to the bodyPart even if it's already holding a dozen gloves, shoes, and millstones (or whatever)
            if (verbose) { Core::print(" inventory checking skipped..."); }
            confirmedBodyPart = currPart;
            break;
        }
        else
        {
            confirmedBodyPart = currPart;        // Assume that the bodypart is valid; we'll invalidate it if we detect too many collisions while looping
            int collisions = 0;
            for (df::unit_inventory_item * currInvItem : unit->inventory)
            {
                if (currInvItem->body_part_id == int32_t(bpIndex))
                {
                    // Collision detected; have we reached the limit?
                    if (++collisions >= multiEquipLimit)
                    {
                        if (verbose) { Core::printerr(" but it already carries %d piece(s) of equipment.  Either remove the existing equipment or use the Multi option.\n", multiEquipLimit); }
                        confirmedBodyPart = NULL;
                        break;
                    }
                }
            }

            if (confirmedBodyPart)
            {
                // Match found; no need to examine any other BPs
                if (verbose) { Core::print(" eligibility confirmed..."); }
                break;
            }
            else if (!targetBodyPart)
            {
                // This body part is not eligible to receive the specified equipment; return to the loop and check the next BP
                continue;
            }
            else
            {
                // A specific body part was designated in the function call, but it was found to be ineligible.
                // Don't return to the BP loop; just fall-through to the failure-reporting code a few lines below.
                break;
            }
        }
    }

    if (!confirmedBodyPart) {
        // No matching body parts found; report failure
        if (verbose) { Core::printerr("\nThe item could not be equipped because the relevant body part(s) of the unit are missing or already occupied.  Try again with the Multi option if you're like to over-equip a body part, or choose a different unit-item combination (e.g. stop trying to put shoes on a trout).\n" ); }
        return false;
    }

    if (!Items::moveToInventory(mc, item, unit, df::unit_inventory_item::Worn, bpIndex))
    {
        if (verbose) { Core::printerr("\nEquipping failed - failed to retrieve item from its current location/container/inventory.  Please move it to the ground and try again.\n"); }
        return false;
    }

    if (verbose) { Core::print("  Success!\n"); }
    return true;
}


command_result df_forceequip(color_ostream &out, vector <string> & parameters)
{
    // The "here" option is hardcoded to true, because the plugin currently doesn't support
    // equip-at-a-distance (e.g. grab items within 10 squares of the targeted unit)
    bool here = true;
    (void)here;
    // For balance (anti-cheating) reasons, the plugin applies a limit on the number of
    // item that can be equipped on any bodypart.  This limit defaults to 1 but can be
    // overridden with cmdline switches.
    int multiEquipLimit = 1;
    // The plugin applies several pre-checks in order to reduce the risk of conflict
    // and unintended side-effects.  Most of these checks can be disabled via cmdline
    bool ignore = false;
    // By default, the plugin uses all gear piled on the selected square.  Optionally,
    // it can target only a single item (selected on the k menu) instead
    bool selected = false;
    // Most of the plugin's text output is suppressed by default.  It can be enabled
    // to provide insight into errors, and/or for debugging purposes.
    bool verbose = false;
    // By default, the plugin will mate each item to an appropriate bodypart.  This
    // behaviour can be skipped if the user specifies a particular BP in the cmdline input.
    std::string targetBodyPartCode;

    // Parse the input
    for (size_t i = 0; i < parameters.size(); i++)
    {
        string & p = parameters[i];

        if (p == "help" || p == "?" || p == "h" || p == "/?" || p == "info" || p == "man")
        {
            return CR_WRONG_USAGE;
        }
        else if (p == "here" || p == "h")
        {
            here = true;
        }
        else if (p == "ignore" || p == "i")
        {
            ignore = true;
        }
        else if (p == "multi" || p == "m")
        {
            multiEquipLimit = INT_MAX;
        }
        else if (p == "m2")
        {
            multiEquipLimit = 2;
        }
        else if (p == "m3")
        {
            multiEquipLimit = 3;
        }
        else if (p == "m4")
        {
            multiEquipLimit = 4;
        }
        else if (p == "selected" || p == "s")
        {
            selected = true;
        }
        else if (p == "verbose" || p == "v")
        {
            verbose = true;
        }
        else if (p == "bodypart" || p == "bp" )
        {
            // must be followed by bodypart code (e.g. NECK)
            if(i == parameters.size()-1 || parameters[i+1].size() == 0)
            {
                out.printerr("The bp switch must be followed by a bodypart code!\n");
                return CR_FAILURE;
            }
            targetBodyPartCode = parameters[i+1];
            i++;
        }
        else
        {
            out << p << ": Unknown command!  Type \"forceequip help\" for assistance." << endl;
            return CR_FAILURE;
        }
    }

    // Ensure that the map information is available (e.g. a game is actually in-progress)
    if (!Maps::IsValid())
    {
        out.printerr("Map is not available!\n");
        return CR_FAILURE;
    }

    // Lookup the cursor position
    int cx, cy, cz;
    DFCoord pos_cursor;

    // needs a cursor
    if (!Gui::getCursorCoords(cx,cy,cz))
    {
        out.printerr("Cursor position not found. Please enable the cursor.\n");
        return CR_FAILURE;
    }
    pos_cursor = DFCoord(cx,cy,cz);

    // Iterate over all units, process the first one whose pos == pos_cursor
    df::unit * targetUnit = nullptr;
    size_t numUnits = world->units.all.size();
    for(size_t i=0; i< numUnits; i++)
    {
        targetUnit = world->units.all[i];    // tentatively assume that we have a match; then verify
        DFCoord pos_unit(targetUnit->pos.x, targetUnit->pos.y, targetUnit->pos.z);

        if (pos_unit == pos_cursor)
            break;

        targetUnit = nullptr;
    }

    if (!targetUnit)
    {
        out.printerr("No unit found at cursor!\n");
        return CR_FAILURE;
    }

    // Assert: unit found.

    // If a specific bodypart was included in the command arguments, then search for it now
    df::body_part_raw * targetBodyPart = NULL;
    if (targetBodyPartCode.size() > 0) {
        for (size_t bpIndex = 0; bpIndex < targetUnit->body.body_plan->body_parts.size(); bpIndex ++)
        {
            // Tentatively assume that the part is a match
            targetBodyPart = targetUnit->body.body_plan->body_parts.at(bpIndex);
            if (targetBodyPart->token.compare(targetBodyPartCode) == 0)
            {
                // It is indeed a match; exit the loop (while leaving the variable populated)
                if (verbose) { out.print("Matching bodypart (%s) found.\n", targetBodyPart->token.c_str()); }
                break;
            }
            else
            {
                // Not a match; nullify the variable (it will get re-populated on the next pass through the loop)
                if (verbose) { out.printerr("Bodypart \"%s\" does not match \"%s\".\n", targetBodyPart->token.c_str(), targetBodyPartCode.c_str()); }
                targetBodyPart = NULL;
            }
        }

        if (!targetBodyPart)
        {
            // Loop iteration is complete but no match was found.
            out.printerr("The unit does not possess a bodypart of type \"%s\".  Please check the spelling or choose a different unit.\n", targetBodyPartCode.c_str());
            return CR_FAILURE;
        }
    }

    // Search for item(s)
    MapCache mc;

    // iterate over all items, process those where pos == pos_cursor
    int itemsEquipped = 0;
    int itemsFound = 0;
    int numItems = world->items.all.size();        // Normally, we iterate through EVERY ITEM in the world.  This is expensive, but currently necessary.
    if (selected) { numItems = 1; }                // If the user wants to process only the selected item, then the loop is trivialized (only one pass is needed).
    for(int i=0; i< numItems; i++)
    {
        df::item * currentItem;

        // Search behaviour depends on whether the operation is driven by cursor location or UI selection
        if (selected)
        {
            // The "search" is trivial - the selection must always cover either one or zero items
            currentItem = Gui::getSelectedItem(out);
            if (!currentItem) { return CR_FAILURE; }
        }
        else
        {
            // Lookup the current item in the world-space
            currentItem = world->items.all[i];
            // Test the item's position
            DFCoord pos_item(currentItem->pos.x, currentItem->pos.y, currentItem->pos.z);
            if (pos_item != pos_cursor)
            {
                // The item is in the wrong place; skip it
                // Note: we do not emit any notification, even with the "verbose" switch, because the search space is enormous and we'd invariably flood the UI with useless text
                continue;
            }
            // Bypass any forbidden items
            else if (currentItem->flags.bits.forbid == 1)
            {
                // The item is forbidden; skip it
                if (verbose) { out.printerr("Forbidden item encountered; skipping to next item.\n"); }
            }

        }

        // Test the item; check whether we have any grounds to disqualify/reject it
        if (currentItem->flags.bits.in_inventory == 1)
        {
            // The item is in a unit's inventory; skip it
            if (verbose) { out.printerr("Inventory item encountered; skipping to next item.\n"); }
        }
        else
        {
            itemsFound ++;                        // Track the number of items found under the cursor (for feedback purposes)
            if (moveToInventory(mc, currentItem, targetUnit, targetBodyPart, ignore, multiEquipLimit, verbose))
            {
//                // TODO TEMP EXPERIMENTAL - try to alter the item size in order to conform to its wearer
//                currentItem->getRace();
//                out.print("Critter size: %d| %d | Armor size: %d", world->raws.creatures.all[targetUnit->race]->caste[targetUnit->caste]->body_size_1, world->raws.creatures.all[targetUnit->race]->caste[targetUnit->caste]->body_size_2, currentItem->getTotalDimension());

                itemsEquipped++;                // Track the number of items successfully processed (for feedback purposes)
            }
        }
    }

    if (itemsFound == 0) {
        out.printerr("No usable items found at the cursor position.  Please choose a different location and try again.\n");
        return CR_OK;
    }


    if (itemsEquipped == 0 && !verbose) { out.printerr("Some items were found but no equipment changes could be made.  Use the /verbose switch to display the reasons for failure.\n"); }
    if (itemsEquipped > 0) { out.print("%d items equipped.\n", itemsEquipped); }
    // At this point, some changes may have been made (such as detaching items from their original position), regardless of whether any equipment changes succeeded.
    // Therefore, we must update the map.
    mc.WriteAll();

    // Note: we might expect to recalculate the unit's weight at this point, in order to account for the
    // added items.  In fact, this recalculation occurs automatically during each dwarf's "turn".
    // The slight delay in recalculation is probably not worth worrying about.

    // Work complete; report success
    return CR_OK;
}