//
// Fl_File_Browser routines.
//
// Copyright 1999-2010 by Michael Sweet.
// Copyright 2016 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
//     https://www.fltk.org/bugs.php
//
// Contents:
//
//   Fl_File_Browser::full_height()     - Return the height of the list.
//   Fl_File_Browser::item_height()     - Return the height of a list item.
//   Fl_File_Browser::item_width()      - Return the width of a list item.
//   Fl_File_Browser::item_draw()       - Draw a list item.
//   Fl_File_Browser::Fl_File_Browser() - Create a Fl_File_Browser widget.
//   Fl_File_Browser::load()            - Load a directory into the browser.
//   Fl_File_Browser::filter()          - Set the filename filter.
//

//
// Include necessary header files...
//

#include <FL/Fl_File_Browser.H>
#include <FL/Fl.H>
#include "Fl_System_Driver.H"
#include <FL/fl_draw.H>
#include <FL/filename.H>
#include <FL/fl_string_functions.h>
#include <FL/Fl_Image.H>        // icon
#include <stdio.h>
#include <stdlib.h>
#include "flstring.h"

//
// FL_BLINE definition from "Fl_Browser.cxx"...
//

#define SELECTED 1
#define NOTDISPLAYED 2

// TODO -- Warning: The definition of FL_BLINE here is a hack.
//    Fl_File_Browser should not do this. PLEASE FIX.
//    FL_BLINE should be private to Fl_Browser, and not re-defined here.
//    For now, make sure this struct is precisely consistent with Fl_Browser.cxx.
//
struct FL_BLINE                 // data is in a linked list of these
{
  FL_BLINE      *prev;          // Previous item in list
  FL_BLINE      *next;          // Next item in list
  void          *data;          // Pointer to data (function)
  Fl_Image      *icon;          // Pointer to optional icon
  short         length;         // sizeof(txt)-1, may be longer than string
  char          flags;          // selected, displayed
  char          txt[1];         // start of allocated array
};


//
// 'Fl_File_Browser::full_height()' - Return the height of the list.
//

int                                     // O - Height in pixels
Fl_File_Browser::full_height() const
{
  int   i,                              // Looping var
        th;                             // Total height of list.


  for (i = 0, th = 0; i < size(); i ++)
    th += item_height(find_line(i));

  return (th);
}


//
// 'Fl_File_Browser::item_height()' - Return the height of a list item.
//

int                                     // O - Height in pixels
Fl_File_Browser::item_height(void *p) const     // I - List item data
{
  FL_BLINE      *line;                  // Pointer to line
  char          *t;                     // Pointer into text
  int           height;                 // Width of line
  int           textheight;             // Height of text


  // Figure out the standard text height...
  fl_font(textfont(), textsize());
  textheight = fl_height();

  // We always have at least 1 line...
  height = textheight;

  // Scan for newlines...
  line = (FL_BLINE *)p;

  if (line != NULL)
    for (t = line->txt; *t != '\0'; t ++)
      if (*t == '\n')
        height += textheight;

  // If we have enabled icons then add space for them...
  if (Fl_File_Icon::first() != NULL && height < iconsize_)
    height = iconsize_;

  // Add space for the selection border..
  height += 2;

  // Return the height
  return (height);
}


//
// 'Fl_File_Browser::item_width()' - Return the width of a list item.
//

int                                     // O - Width in pixels
Fl_File_Browser::item_width(void *p) const      // I - List item data
{
  int           i;                      // Looping var
  FL_BLINE      *line;                  // Pointer to line
  char          *t,                     // Pointer into text
                *ptr,                   // Pointer into fragment
                fragment[10240];        // Fragment of text
  int           width,                  // Width of line
                tempwidth;              // Width of fragment
  int           column;                 // Current column
  const int     *columns;               // Columns


  // Scan for newlines...
  line    = (FL_BLINE *)p;
  columns = column_widths();

  // Set the font and size...
  if (line->txt[strlen(line->txt) - 1] == '/')
    fl_font(textfont() | FL_BOLD, textsize());
  else
    fl_font(textfont(), textsize());

  if (strchr(line->txt, '\n') == NULL &&
      strchr(line->txt, column_char()) == NULL)
  {
    // Do a fast width calculation...
    width = (int)fl_width(line->txt);
  }
  else
  {
    // More than 1 line or have columns; find the maximum width...
    width     = 0;
    tempwidth = 0;
    column    = 0;

    for (t = line->txt, ptr = fragment; *t != '\0'; t ++)
      if (*t == '\n')
      {
        // Newline - nul terminate this fragment and get the width...
        *ptr = '\0';

        tempwidth += (int)fl_width(fragment);

        // Update the max width as needed...
        if (tempwidth > width)
          width = tempwidth;

        // Point back to the start of the fragment...
        ptr       = fragment;
        tempwidth = 0;
        column    = 0;
      }
      else if (*t == column_char())
      {
        // Advance to the next column...
        column ++;
        if (columns)
        {
          for (i = 0, tempwidth = 0; i < column && columns[i]; i ++)
            tempwidth += columns[i];
        }
        else
          tempwidth = column * (int)(fl_height() * 0.6 * 8.0);

        if (tempwidth > width)
          width = tempwidth;

        ptr = fragment;
      }
      else
        *ptr++ = *t;

    if (ptr > fragment)
    {
      // Nul terminate this fragment and get the width...
      *ptr = '\0';

      tempwidth += (int)fl_width(fragment);

      // Update the max width as needed...
      if (tempwidth > width)
        width = tempwidth;
    }
  }

  // If we have enabled icons then add space for them...
  if (Fl_File_Icon::first() != NULL)
    width += iconsize_ + 8;

  // Add space for the selection border..
  width += 2;

  // Return the width
  return (width);
}


//
// 'Fl_File_Browser::item_draw()' - Draw a list item.
//

void
Fl_File_Browser::item_draw(void *p,     // I - List item data
                           int  X,      // I - Upper-lefthand X coordinate
                           int  Y,      // I - Upper-lefthand Y coordinate
                           int  W,      // I - Width of item
                           int) const   // I - Height of item
{
  int           i;                      // Looping var
  FL_BLINE      *line;                  // Pointer to line
  Fl_Color      c;                      // Text color
  char          *t,                     // Pointer into text
                *ptr,                   // Pointer into fragment
                fragment[10240];        // Fragment of text
  int           width,                  // Width of line
                height;                 // Height of line
  int           column;                 // Current column
  const int     *columns;               // Columns


  // Draw the list item text...
  line = (FL_BLINE *)p;

  if (line->txt[strlen(line->txt) - 1] == '/')
    fl_font(textfont() | FL_BOLD, textsize());
  else
    fl_font(textfont(), textsize());

  if (line->flags & SELECTED)
    c = fl_contrast(textcolor(), selection_color());
  else
    c = textcolor();

  if (Fl_File_Icon::first() == NULL)
  {
    // No icons, just draw the text...
    X ++;
    W -= 2;
  }
  else
  {
    // Draw the icon if it is set...
    if (line->data)
      ((Fl_File_Icon *)line->data)->draw(X, Y, iconsize_, iconsize_,
                                        (line->flags & SELECTED) ? FL_YELLOW :
                                                                   FL_LIGHT2,
                                        active_r());

    // Draw the text offset to the right...
    X += iconsize_ + 9;
    W -= iconsize_ - 10;

    // Center the text vertically...
    height = fl_height();

    for (t = line->txt; *t != '\0'; t ++)
      if (*t == '\n')
        height += fl_height();

    if (height < iconsize_)
      Y += (iconsize_ - height) / 2;
  }

  // Draw the text...
  line    = (FL_BLINE *)p;
  columns = column_widths();
  width   = 0;
  column  = 0;

  if (active_r())
    fl_color(c);
  else
    fl_color(fl_inactive(c));

  for (t = line->txt, ptr = fragment; *t != '\0'; t ++) {
    if (*t == '\n') {
      // Newline - nul terminate this fragment and draw it...
      *ptr = '\0';

      fl_draw(fragment, X + width, Y, W - width, fl_height(),
              (Fl_Align)(FL_ALIGN_LEFT | FL_ALIGN_CLIP), 0, 0);

      // Point back to the start of the fragment...
      ptr    = fragment;
      width  = 0;
      Y      += fl_height();
      column = 0;
    } else if (*t == column_char()) {
      // Tab - nul terminate this fragment and draw it...
      *ptr = '\0';

      int cW = W - width; // Clip width...

      if (columns) {
        // Try clipping inside this column...
        for (i = 0; i < column && columns[i]; i ++) { ; }

        if (columns[i])
          cW = columns[i];
      }

      fl_draw(fragment, X + width, Y, cW, fl_height(),
              (Fl_Align)(FL_ALIGN_LEFT | FL_ALIGN_CLIP), 0, 0);

      // Advance to the next column...
      column ++;
      if (columns) {
        for (i = 0, width = 0; i < column && columns[i]; i ++)
          width += columns[i];
      }
      else
        width = column * (int)(fl_height() * 0.6 * 8.0);
      ptr = fragment;
    }
    else
      *ptr++ = *t;
  }
  if (ptr > fragment) {
    // Nul terminate this fragment and draw it...
    *ptr = '\0';

    fl_draw(fragment, X + width, Y, W - width, fl_height(),
            (Fl_Align)(FL_ALIGN_LEFT | FL_ALIGN_CLIP), 0, 0);
  }
}


/**
  The constructor creates the Fl_File_Browser widget at the specified position and size.
  The destructor destroys the widget and frees all memory that has been allocated.
*/
Fl_File_Browser::Fl_File_Browser(int        X,  // I - Upper-lefthand X coordinate
                                 int        Y,  // I - Upper-lefthand Y coordinate
                                 int        W,  // I - Width in pixels
                                 int        H,  // I - Height in pixels
                                 const char *l) // I - Label text
    : Fl_Browser(X, Y, W, H, l)
{
  // Initialize the filter pattern, current directory, and icon size...
  pattern_   = "*";
  directory_ = "";
  iconsize_  = (uchar)(3 * textsize() / 2);
  filetype_  = FILES;
  errmsg_    = NULL;
}


// DTOR
Fl_File_Browser::~Fl_File_Browser() {
  errmsg(NULL);       // free()s prev errmsg, if any
}


/**
  Sets OS error message to a string, which can be NULL.
  Frees previous if any.
  void errmsg(const char *emsg);
 */
void Fl_File_Browser::errmsg(const char* emsg) {
  if ( errmsg_ ) { free((void*)errmsg_); errmsg_ = NULL; }
  errmsg_ = emsg ? fl_strdup(emsg) : NULL;
}


/**
  Loads the specified directory into the browser. If icons have been
  loaded then the correct icon is associated with each file in the list.

  If directory is "", all mount points (unix) or drive letters (Windows)
  are listed.

  The sort argument specifies a sort function to be used with
  fl_filename_list().

  Return value is the number of filename entries, or 0 if none.
  On error, 0 is returned, and errmsg() has OS error string if non-NULL.
*/
int                                             // O - Number of files loaded
Fl_File_Browser::load(const char     *directory,// I - Directory to load
                      Fl_File_Sort_F *sort)     // I - Sort function to use
{
  int           i;                              // Looping var
  int           num_files;                      // Number of files in directory
  int           num_dirs;                       // Number of directories in list
  char          filename[4096];                 // Current file
  Fl_File_Icon  *icon;                          // Icon to use

  errmsg(NULL); // clear errors first

//  printf("Fl_File_Browser::load(\"%s\")\n", directory);

  clear();

  directory_ = directory;

  if (!directory) {
    errmsg("NULL directory specified");
    return 0;
  }

  if (directory_[0] == '\0') {
    //
    // No directory specified; for UNIX list all mount points.  For DOS
    // list all valid drive letters...
    //
    if ((icon = Fl_File_Icon::find("any", Fl_File_Icon::DEVICE)) == NULL)
      icon = Fl_File_Icon::find("any", Fl_File_Icon::DIRECTORY);
    num_files = Fl::system_driver()->file_browser_load_filesystem(this, filename, (int)sizeof(filename), icon);
  } else {
    dirent **files;        // Files in in directory
    char emsg[1024] = "";

    // Build the file list, check for errors
    num_files = Fl::system_driver()->file_browser_load_directory(directory_,
                                                                 filename, sizeof(filename),
                                                                 &files, sort,
                                                                 emsg, sizeof(emsg));
    // printf("Fl_File_Browser::load(dir='%s',filename='%s'): failed, emsg='%s'\n", directory_, filename, emsg);

    if (num_files <= 0) {
      errmsg(emsg);
      return 0;
    }

    for (i = 0, num_dirs = 0; i < num_files; i ++) {
      if (strcmp(files[i]->d_name, "./")) {
        fl_snprintf(filename, sizeof(filename), "%s/%s", directory_, files[i]->d_name);

        icon = Fl_File_Icon::find(filename);
        if ((icon && icon->type() == Fl_File_Icon::DIRECTORY) ||
            Fl::system_driver()->filename_isdir_quick(filename)) {
          num_dirs ++;
          insert(num_dirs, files[i]->d_name, icon);
        } else if (filetype_ == FILES &&
                   fl_filename_match(files[i]->d_name, pattern_)) {
          add(files[i]->d_name, icon);
        }
      }

      free(files[i]);
    }

    free(files);
  }

  return (num_files);
}


//
// 'Fl_File_Browser::filter()' - Set the filename filter.
//

void
Fl_File_Browser::filter(const char *pattern)    // I - Pattern string
{
  // If pattern is NULL set the pattern to "*"...
  if (pattern)
    pattern_ = pattern;
  else
    pattern_ = "*";
}
