Working product with sustainable legacies

README.md

@@ -0,0 +1,21 @@
+Geachte speler,
+
+Heb je wel eens rijk willen zijn?
+
+Vast wel. Mensen met goede bedoelingen (zoals ik) hebben jouw daarom
+meermaals geappt op Telegram om je te vragen of je bij een bedrijf
+XYZ wilt werken. De werktijden zijn slechts 30 min per week, en je
+verdient 500 euro per dag!
+
+Misschien twijfel je nog. Geen probleem! Voor kleine spelers zoals
+jij hebben we een spel genaamd 'gambling-curses'. In dit spel zie je
+een live grafiek van de laatste Bitcoin-prijs, en heb je 10.000
+euro op je bankaccount.  Je kunt gemakkelijk traden door op 's' en
+'b' te klikken. ('s' betekent SELL, 'b' betekent BUY).
+
+Aangezien de cryptomarkt zeker NIET gamblen is, en er wel degelijk
+een strategie achter zit, kun je zo gaan oefenen.
+
+Met vriendelijke groet,
+
+Crypto/Dropshipping Guru

box.c

@@ -17,13 +17,14 @@
 #include "util.h"
 
 
-static void draw_rectangle(double x, double y, double width, double height);
+static void draw_rectangle(unsigned int x, unsigned int y, unsigned int width,
-static void draw_chart(struct box *, double x, double y, double width,
+    unsigned int height);
-    double height);
+static void draw_chart(struct box *, unsigned int x, unsigned int y,
-static void draw_container(struct box *, double x, double y, double width,
+    unsigned int width, unsigned int height);
-    double height);
+static void draw_container(struct box *, unsigned int x, unsigned int y,
-static void draw_button(struct box *, double x, double y, double width,
+    unsigned int width, unsigned int height);
-    double height);
+static void draw_button(struct box *, unsigned int x, unsigned int y,
+    unsigned int width, unsigned int height);
 
 
 void
@@ -34,44 +35,41 @@ append_box(struct box *parent, struct box *child)
 
 
 static void
-draw_rectangle(double fx, double fy, double fwidth, double fheight)
+draw_rectangle(unsigned int x, unsigned int y, unsigned int width,
+    unsigned int height)
 {
-    size_t x = llround(fx);
-    size_t y = llround(fy);
-    size_t w = llround(fwidth) - 1;
-    size_t h = llround(fheight) - 1;
-
     /* corners */
 
     ui_char(x, y, '+');
-    ui_char(x, y + h, '+');
+    ui_char(x, y + height, '+');
-    ui_char(x + w, y + h, '+');
+    ui_char(x + width, y + height, '+');
-    ui_char(x + w, y, '+');
+    ui_char(x + width, y, '+');
 
     /* vertical borders */
 
-    for (size_t i = 1; i < h; i++) {
+    for (size_t i = 1; i < height; i++) {
         ui_char(x, y + i, '|');
     }
 
-    for (size_t i = 1; i < h; i++) {
+    for (size_t i = 1; i < height; i++) {
-        ui_char(x + w, y + i, '|');
+        ui_char(x + width, y + i, '|');
     }
 
     /* horizontal borders */
 
-    for (size_t i = 1; i < w; i++) {
+    for (size_t i = 1; i < width; i++) {
         ui_char(x + i, y, '-');
     }
 
-    for (size_t i = 1; i < w; i++) {
+    for (size_t i = 1; i < width; i++) {
-        ui_char(x + i, y + h, '-');
+        ui_char(x + i, y + height, '-');
     }
 }    
 
 
 static void
-draw_chart(struct box *chart, double x, double y, double width, double height)
+draw_chart(struct box *chart, unsigned int x, unsigned int y,
+    unsigned int width, unsigned int height)
 {
     long int actual_diff;
     double diff, price;
@@ -98,7 +96,8 @@ draw_chart(struct box *chart, double x, double y, double width, double height)
 
 
 static void
-draw_button(struct box *b, double x, double y, double width, double height)
+draw_button(struct box *b, unsigned int x, unsigned int y, unsigned int width,
+    unsigned int height)
 {
     ui_color_on(b->color);
     draw_rectangle(x, y, width, height);
@@ -108,10 +107,11 @@ draw_button(struct box *b, double x, double y, double width, double height)
 
 
 static void
-draw_container(struct box *b, double x, double y, double width, double height)
+draw_container(struct box *b, unsigned int x, unsigned int y,
+    unsigned int width, unsigned int height)
 {
-    double       current, length, total_fills, pixels_per_fill;
+    unsigned int   current, i, length, total_fills, pixels_per_fill;
-    struct box  *child;
+    struct box    *child;
 
     switch (b->type) {
     case BOX_VERTICAL:
@@ -125,13 +125,13 @@ draw_container(struct box *b, double x, double y, double width, double height)
     }
     
     total_fills = 0;
-    for (size_t i = 0; i < b->length; i++) {
+    for (i = 0; i < b->length; i++) {
         total_fills += b->children[i]->fills;
     }
 
     pixels_per_fill = length / total_fills;
 
-    for (size_t i = 0; i < b->length; i++) {
+    for (i = 0; i < b->length; i++) {
         child = b->children[i];
         length = child->fills * pixels_per_fill;
 
@@ -206,7 +206,8 @@ new_vertical_box(void)
 
 
 void
-draw_box(struct box *b, double x, double y, double width, double height)
+draw_box(struct box *b, unsigned int x, unsigned int y, unsigned int width,
+    unsigned int height)
 {
     switch (b->type) {
     case BOX_BUTTON:

box.h

@@ -22,7 +22,7 @@ enum box_type {
 struct box {
     enum box_type type;
     enum ui_color color;
-    double fills;
+    unsigned int fills;
 
     union {
         /* button */
@@ -47,4 +47,5 @@ struct box *new_chart_box(struct chart *);
 
 void append_box(struct box *parent, struct box *child);
 
-void draw_box(struct box *, double x, double y, double width, double height);
+void draw_box(struct box *, unsigned int x, unsigned int y, unsigned int width,
+    unsigned int height);

chart.c

@@ -6,11 +6,14 @@
 
 
 #include <stdlib.h>
+#include <string.h>
+
 #include "chart.h"
 #include "util.h"
 
 
-struct chart new_chart(unsigned int length)
+struct chart
+new_chart(unsigned int length)
 {
     unsigned int  i;
     double        price;
@@ -25,8 +28,16 @@ struct chart new_chart(unsigned int length)
     
     for (i = 0; i < length; i++) {
         chart.prices[i] = price;
-        price += (double)rand() / RAND_MAX - 0.4;
+        price += (double)rand() / RAND_MAX * 4 - 2;
     }
 
     return chart;
 }
+
+
+void
+update_chart(struct chart *chart)
+{
+    memmove(chart->prices, chart->prices + 1, (chart->length - 1) * sizeof(double));
+    chart->prices[chart->length - 1] = chart->prices[chart->length - 2] + (double)rand() / RAND_MAX * 4 - 2;
+}

chart.h

@@ -14,4 +14,5 @@ struct chart {
 };
 
 
+void update_chart(struct chart *);
 struct chart new_chart(unsigned int length);

main.c

@@ -5,23 +5,36 @@
  */
  
 
+#include <curses.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <curses.h>
+#include <time.h>
 
 #include "box.h"
 #include "ui.h"
+#include "util.h"
 
 
-int
+enum game_state {
-main(void)
+    GAME_IDLE,   /* can buy AND sell */
+    GAME_BOUGHT, /* cannot buy again */
+    GAME_SOLD,   /* cannot sell again */
+};
+
+struct game {
+    unsigned int     dollars;
+    struct chart     chart;  
+    enum game_state  state;
+};
+
+
+struct box *
+initialize_ui_from_game(struct game *game)
 {
-    struct box    *ui, *top, *bottom, *left, *right, *buy, *sell, *scam,
+    struct box    *ui, *top, *bottom, *left, *right, *buy, *sell, *bank,
                   *title, *desc;
-    struct chart   chart;
+    
-
-    ui_init();
-
     title = new_button_box("Bitcoin");
     desc = new_button_box("A crypto-scam :-)");
 
@@ -29,21 +42,25 @@ main(void)
     append_box(top, title);
     append_box(top, desc);
 
-    chart = new_chart(400);
+    left = new_chart_box(&game->chart);
-    left = new_chart_box(&chart);
     left->fills = 5;
 
     buy = new_button_box("buy");
     buy->color = UI_GREEN;
     sell = new_button_box("sell");
     sell->color = UI_RED;
-    scam = new_button_box("scam");
+
+    char *bank_text = emalloc(500);
+
+    sprintf(bank_text, "YOU HAVE $%d.", game->dollars);
+    
+    bank = new_button_box(bank_text);
     sell->color = UI_BLUE;
 
     right = new_vertical_box();
     append_box(right, buy);
     append_box(right, sell);
-    append_box(right, scam);
+    append_box(right, bank);
 
     bottom = new_horizontal_box();
     bottom->fills = 3;
@@ -54,11 +71,82 @@ main(void)
     append_box(ui, top);
     append_box(ui, bottom);
 
-    draw_box(ui, 0, 0, ui_width(), ui_height());
+    return ui;
+}
 
-    ui_refresh();
+
-    
+/*
-    sleep(300);
+ * Buy 50 coins, price = last price in chart.
+ */
+void game_buy(struct game *game)
+{
+    if (game->state != GAME_IDLE) {
+        return;
+    }
+
+    game->dollars -= game->chart.prices[game->chart.length - 1] * 50;
+    game->state = GAME_BOUGHT;
+}
+
+
+/*
+ * Sell 50 coins, price = last price in chart.
+ */
+void game_sell(struct game *game)
+{
+    if (game->state != GAME_BOUGHT) {
+        return;
+    }
+
+    game->dollars += game->chart.prices[game->chart.length - 1] * 50;
+    game->state = GAME_IDLE;
+}
+
+
+int
+main(void)
+{
+    int           framerate;
+    struct box   *ui;
+    struct game   game;
+
+    framerate = 10;
+
+    game.state = GAME_IDLE;
+    game.dollars = 10000;
+    game.chart = new_chart(200);
+
+    ui_init();
+
+    ui = initialize_ui_from_game(&game);
+
+    for (;;) {
+        draw_box(ui, 0, 0, ui_width(), ui_height());
+
+        ui_refresh();
+
+        clock_t current = clock();
+        clock_t max = current + CLOCKS_PER_SEC * (1.0/framerate);
+
+        for (;;) {
+            switch (getch()) {
+            case 'b':
+                game_buy(&game);
+                break;
+            case 's':
+                game_sell(&game);
+                break;
+            }
+
+            if (clock() >= max) {
+                break;
+            }
+        }
+        
+        update_chart(&game.chart);
+        ui_clear();
+        ui = initialize_ui_from_game(&game);
+    }
 
     ui_end();
 }

ui.c

@@ -22,6 +22,7 @@ ui_init(void)
     init_pair(UI_BLUE,  COLOR_BLUE,  COLOR_BLACK);
     cbreak();
     noecho();
+    nodelay(stdscr, TRUE);
     nonl();
     intrflush(stdscr, FALSE);
     keypad(stdscr, TRUE);
@@ -34,12 +35,12 @@ void ui_end()
     endwin();
 }
 
-void ui_string(size_t x, size_t y, char *s)
+void ui_string(unsigned int x, unsigned int y, char *s)
 {
     mvaddstr(y, x, s);
 }
 
-void ui_char(size_t x, size_t y, char c)
+void ui_char(unsigned int x, unsigned int y, char c)
 {
     mvaddch(y, x, c);
 }

ui.h

@@ -22,8 +22,8 @@ void ui_end(void);
 void ui_color_on(enum ui_color);
 void ui_color_off(enum ui_color);
 
-void ui_char(size_t x, size_t y, char c);
+void ui_char(unsigned int x, unsigned int y, char c);
-void ui_string(size_t x, size_t y, char *s);
+void ui_string(unsigned int x, unsigned int y, char *s);
 
 size_t ui_width(void);
 size_t ui_height(void);