#include <stdio.h>
#include <stdlib.h>
#include <X11/Xlib.h>
#include <X11/extensions/Xrandr.h>
#include "dat.h"
#include "fns.h"
#include "config.h"

int nmonitors = 0;
XRRMonitorInfo* monitorinfo;
int* xstep;
int* ystep;

void fetchmonitorinfo() {
  if (monitorinfo)
    XRRFreeMonitors(monitorinfo);
  if (xstep)
    free(xstep);
  if (ystep)
    free(ystep);

  monitorinfo = XRRGetMonitors(dpy, DefaultRootWindow(dpy), 1, &nmonitors);
  xstep = malloc(nmonitors * sizeof(int));
  ystep = malloc(nmonitors * sizeof(int));
  for (int i = 0; i < nmonitors; i++) {
    xstep[i] = monitorinfo[i].width / CASCADE_DENSITY;
    ystep[i] = monitorinfo[i].height / CASCADE_DENSITY;
  }
}

void getcascadecoords(Window w, int monitor, int* x, int* y) {
  int mappedclients = 0;
  Client* c;
  int ox = monitorinfo[monitor].x;
  int oy = monitorinfo[monitor].y;

  if (w == 0)
    return;
  for (c = clients; c; c = c->next) {
    if (
      c->window != w && c->state == NormalState &&
      getmonitorbyclient(c) == monitor) {
      mappedclients++;
    }
  }
  for (;;) {
    if (mappedclients < CASCADE_DENSITY) {
      *x = ox + mappedclients * xstep[monitor];
      *y = oy + mappedclients * ystep[monitor];
      return;
    } else if (mappedclients < 1.5 * CASCADE_DENSITY) {
      *x = ox + (mappedclients - CASCADE_DENSITY + 1) * xstep[monitor];
      *y = oy + (mappedclients - CASCADE_DENSITY) * ystep[monitor];
      return;
    } else if (mappedclients < 2 * CASCADE_DENSITY) {
      *x = ox + (mappedclients - 1.5 * CASCADE_DENSITY) * xstep[monitor];
      *y = oy + (mappedclients - 1.5 * CASCADE_DENSITY + 1) * ystep[monitor];
      return;
    } else {
      mappedclients -= 2 * CASCADE_DENSITY;
    }
  }
}

int getmonitorbyclient(Client* c) {
  XRRMonitorInfo m;
  int cx, cy, i, p;
  cx = cy = 0;

  /* we check which monitor the center of the window is in */
  if (c) {
    cx = c->x + c->dx / 2;
    cy = c->y + c->dy / 2;
  }

  p = 0;

  for (i = 0; i < nmonitors; i++) {
    m = monitorinfo[i];
    if (
      c && cx >= m.x && cx < m.x + m.width && cy >= m.y &&
      cy < m.y + m.height) {
      return i;
    }

    if (m.primary) {
      p = i;
    }
  }

  /* if center is not within any monitor, return primary */
  return p;
}

int getmonitorbymouse() {
  Window w;
  int x, y, i;
  unsigned int mask;
  XRRMonitorInfo m;

  XQueryPointer(dpy, DefaultRootWindow(dpy), &w, &w, &x, &y, &x, &y, &mask);
  for (i = 0; i < nmonitors; i++) {
    m = monitorinfo[i];
    if (x >= m.x && x < m.x + m.width && y >= m.y && y < m.y + m.height) {
      return i;
    }
  }
  /* should never reach here, but return first monitor if we do */
  return 0;
}

void wrangle(Client* c, XRRMonitorInfo monitor) {

  if (!c)
    return;

  /* If it's bigger than the screen, try to set it maximized */

  if (c->dx >= monitor.width && c->dy >= monitor.height) {
    quickreshape(c, monitor.x, monitor.y, monitor.width, monitor.height, 1);
    /* and if it's got an edge out of bounds, nudge it into bounds */
  } else {
    if (c->x < monitor.x + BORDER) {
      quickreshape(
        c,
        monitor.x,
        c->y - BORDER,
        c->dx + 2 * BORDER,
        c->dy + 2 * BORDER,
        0);
    }
    if (c->y < monitor.y + BORDER) {
      quickreshape(
        c,
        c->x - BORDER,
        monitor.y,
        c->dx + 2 * BORDER,
        c->dy + 2 * BORDER,
        0);
    }
    if (c->x + c->dx + BORDER > monitor.x + monitor.width) {
      quickreshape(
        c,
        monitor.x + monitor.width - (c->dx + 2 * BORDER),
        c->y - BORDER,
        c->dx + 2 * BORDER,
        c->dy + 2 * BORDER,
        0);
    }
    if (c->y + c->dy + BORDER > monitor.y + monitor.height) {
      quickreshape(
        c,
        c->x - BORDER,
        monitor.y + monitor.height - (c->dy + 2 * BORDER),
        c->dx + 2 * BORDER,
        c->dy + 2 * BORDER,
        0);
    }
  }
}