civdos ai wonders (fix 3)

//CIVDOS AI WONDERS RULES v4.0

#define W_DARWINS_VOYAGE    0x0E
#define W_MANHATTAN_PROJECT 0x11

#define T_ROCKETRY 0x2E

void FUN_global_warming_and_ai_wonders()
{
    //skip some global warming code here...

    counter = 0;
    do
    {
        if (counter > difficulty)
            return;
        wond = 1+random(21); //21 - number of wonders
        //for some reason wonders are counting from 1 and not from 0... (1 = pyramids, 2 = gardens etc.)

        if (difficulty != 0 || check_civ_advance(human_player_civ,city_imrpovement_tech[wond]) == 1)
        //on Chieftain difficulty comp. player can build a wonder only if human player
        //has a civ advance to build a city improvement with the same number as this wonder...
        //this can be a bug and intentional behavior was 'if human player has a civ advance to
        //build this wonder', but who knows (except for Sid maybe)...
        {
            if (difficulty < 2) //Chieftain or Warlord
            {
                //this loop prohibits AI to build a wonder if human already is building one...
                //but only if it's not Manhattan Project...
                city = 0;
                do
                {
                    if (city_civ[city] == human_player_civ
                    && city_flags[city] != -1 //city exists
                    && city_production[city] == -(24+wond)) //0 is settler, > 0 are units, -1..-24 are used for buildings and SS parts.
                    {
                        wond = W_MANHATTAN_PROJECT;
                        //why not break here though?
                    }
                    city++;
                }
                while (city < 128);
            }
            city = random(128);
            cit_civ = city_civ[city];
            if (city_flags[city] != -1 //city exists
            && (diplomacy_status[cit_civ][0])&4 == 0 //The civilization is not in anarchy. (third ('ALLY') bit of cit_civ diplomacy with 'barbarians' is 0).
            && (wond != W_MANHATTAN_PROJECT || check_civ_advance(cit_civ,T_ROCKETRY) == 1)) //AI will build Manhattan Proj. only if it can build nukes...
            {
                if (counter == 0
                && check_civ_advance(cit_civ,T_ROCKETRY) == 1 //rocketry is hardcoded, it will not change here if you change prerequisite tech for Nuclear unit...
                && check_civ_advance(human_player_civ,T_ROCKETRY) == 0
                && wonder_city[W_MANHATTAN_PROJECT] == -1) //Manh. Proj. has never been built before...
                {
                    wond = W_MANHATTAN_PROJECT;
                }
                if ((wond != W_MANHATTAN_PROJECT
                || check_civ_advance(human_player_civ,T_ROCKETRY) == 0
                || military_power[cit_civ] <= military_power[human_player_civ]) //if AI is weaker than the player, it can build MP even if the player knows the rocketry...
                &&
                (cit_civ != -1 && cit_civ != human_player_civ
                && wonder_city[wond] == -1)) //wonder never was built before...
                {
                    if (city_size[city] > wonder_shield_rows_cost[wond]/10  //for example: you need 30 rows for Pyramids (300 shields), so AI can build Pyramids only in city with size 4 or more
                    && check_civ_advance(cit_civ,city_improvement_tech[24+wond]) == 1) //after civ advances for city improvements there are civ advances for wonders
                    {
                        city_shields_count[city] = 0;
                        write_replay_entry(10,2,cit_civ,wond); //10 - event type (wonder). 2 - record length.

                        //concatenate some strings for "City (Civilization) builds a wonder" message here...

                        var_B = normalize_min_max(civ_gold[cit_civ]/3,0,wonder_shield_rows_cost[wond]*10-city_shields_count[city]);
                        //AI actually pays for wonders! But not more than 1/3 of the treasury!
                        civ_gold[cit_civ] -= var_B;
                        if (gl_debug_flag_A == 1) //some debug flag: no message about wonder and no civ jingle...
                        {
                            goto LAB_AI_WONDER_ACTIONS;
                        }
                        play_sound(civ_jingle);
                        if ((diplomacy_status[human_player_civ][cit_civ]&0x40)==0) //you don't have an embassy for cit_civ...
                        {
                            var_C = 2; //Travellers report:
                        }
                        else
                        {
                            var_C = 5; //Foreign Minister:
                        }
                        gl_message_type = var_C;
                        var_C = 80;
                        goto LAB_WONDER_MESSAGE;
                    }
                }
            }
        }
        counter++;
    }
    while (1);

    //actually these labels are within some IF block in global warming logic.
    LAB_WONDER_MESSAGE:
    draw_message_function(curr_string,100,var_C); //draw message x: 100, y: 80?

    //software interruption 0x3f here... I think it used to transfer control to graphics exe when game needs to draw something?
    //or/and to check mouse click/key press?..

    black_screen_update_graphics(); //screen fadeout? -> go to civilopedia?..
    play_sound(1); //stop current sound?..
    LAB_AI_WONDER_ACTIONS:
    if (wond == W_DARWINS_VOYAGE)
    {
        get_some_civ_advance(civ,0); //0 - source (discovered by civ itself). Always 0 for every call of this function within the program, so this param is useless...
        get_some_civ_advance(civ,0);
    }
    city = 0;
    while (city < 128)
    {
        if (city_flags[city] != -1 //city exists
        && city_civ[city] == human_player_civ
        && city_production[city] == -(24+wond)) //city is building this wonder...
        {
            goto_city_screen(human_player_civ,city); //you should change it...
        }
        city++;
    }
    return;
}