Fossil

**
** This file contains code to implement the "/doc" web page and related
** pages.
*/
#include "config.h"
#include "doc.h"
#include <assert.h>

/*
** Try to guess the mimetype from content.
**
** If the content is pure text, return NULL.
**
** For image types, attempt to return an appropriate mimetype
** name like "image/gif" or "image/jpeg".  
**
** For any other binary type, return "unknown/unknown".
*/
const char *mimetype_from_content(Blob *pBlob){
  int i;
  int n;
  const unsigned char *x;

  static const char isBinary[] = {
     1, 1, 1, 1,  1, 1, 1, 1,    1, 0, 0, 1,  0, 0, 1, 1,
     1, 1, 1, 1,  1, 1, 1, 1,    1, 1, 1, 0,  1, 1, 1, 1,
  };

  /* A table of mimetypes based on file content prefixes
  */
  static const struct {
    const char *zPrefix;       /* The file prefix */
    int size;                  /* Length of the prefix */
    const char *zMimetype;     /* The corresponding mimetype */
  } aMime[] = {
    { "GIF87a",                  6, "image/gif"  },
    { "GIF89a",                  6, "image/gif"  },
    { "\211PNG\r\n\032\r",       8, "image/png"  },
    { "\377\332\377",            3, "image/jpeg" },
  };

  x = (const unsigned char*)blob_buffer(pBlob);
  n = blob_size(pBlob);
  for(i=0; i<n; i++){
    unsigned char c = x[i];
    if( c<=0x1f && isBinary[c] ){
      break;
    }
  }
  if( i>=n ){
    return 0;   /* Plain text */
  }
  for(i=0; i<sizeof(aMime)/sizeof(aMime[0]); i++){
    if( n>=aMime[i].size && memcmp(x, aMime[i].zPrefix, aMime[i].size)==0 ){
      return aMime[i].zMimetype;
    }
  }
  return "unknown/unknown";
}

/*
** Guess the mime-type of a document based on its name.
*/
const char *mimetype_from_name(const char *zName){
  const char *z;
  int i;

**
** If the object is a manifest, then mention:
**
**     * It's uuid
**     * date of check-in
**     * Comment & user
*/
static void object_description(
  int rid,                 /* The artifact ID */
  int linkToView           /* Add viewer link if true */
){
  Stmt q;
  int cnt = 0;
  int nWiki = 0;

  db_prepare(&q,
    "SELECT filename.name, datetime(event.mtime), substr(a.uuid,1,10),"
    "       coalesce(event.ecomment,event.comment),"
    "       coalesce(event.euser,event.user),"
    "       b.uuid"
    "  FROM mlink, filename, event, blob a, blob b"
    " WHERE filename.fnid=mlink.fnid"

    const char *zCom = db_column_text(&q, 3);
    const char *zUser = db_column_text(&q, 4);
    const char *zVers = db_column_text(&q, 5);
    @ File <a href="%s(g.zBaseURL)/finfo?name=%T(zName)">%h(zName)</a>
    @ uuid %s(zFuuid) part of check-in
    hyperlink_to_uuid(zVers);
    @ %w(zCom) by %h(zUser) on %s(zDate)

    cnt++;
    break;
  }
  db_finalize(&q);
  db_prepare(&q, 
    "SELECT substr(tagname, 6, 10000), datetime(event.mtime),"
    "       coalesce(event.euser, event.user), uuid"
    "  FROM tagxref, tag, event, blob"
    " WHERE tagxref.rid=%d"

    const char *zUser = db_column_text(&q, 2);
    const char *zUuid = db_column_text(&q, 3);
    @ Wiki page
    @ [<a href="%s(g.zBaseURL)/wiki?name=%t(zPagename)">%h(zPagename)</a>]
    @ uuid %s(zUuid) by %h(zUser) on %s(zDate)
    nWiki++;
    cnt++;

  }
  db_finalize(&q);
  if( nWiki==0 ){
    db_prepare(&q,
      "SELECT datetime(mtime), user, comment, uuid, type"
      "  FROM event, blob"
      " WHERE event.objid=%d"

  }
  if( cnt==0 ){
    char *zUuid = db_text(0, "SELECT uuid FROM blob WHERE rid=%d", rid);
    @ Control file %s(zUuid).
  }else if( linkToView ){
    @ <a href="%s(g.zBaseURL)/artifact/%d(rid)">[view]</a>
  }

}

/*
** WEBPAGE: fdiff
**
** Two arguments, v1 and v2, are integers.  Show the difference between
** the two records.

  login_check_credentials();
  if( !g.okRead ){ login_needed(); return; }
  if( rid==0 ){ cgi_redirect("/home"); }
  content_get(rid, &content);
  cgi_set_content_type(zMime);
  cgi_set_content(&content);
}

/*
** Render a hex dump of a file.
*/
static void hexdump(Blob *pBlob){
  const unsigned char *x;
  int n, i, j, k;
  char zLine[100];
  static const char zHex[] = "0123456789abcdef";

  x = (const unsigned char*)blob_buffer(pBlob);
  n = blob_size(pBlob);
  for(i=0; i<n; i+=16){
    j = 0;
    zLine[0] = zHex[(i>>24)&0xf];
    zLine[1] = zHex[(i>>16)&0xf];
    zLine[2] = zHex[(i>>8)&0xf];
    zLine[3] = zHex[i&0xf];
    zLine[4] = ':';
    sprintf(zLine, "%04x: ", i);
    for(j=0; j<16; j++){
      k = 5+j*3;
      zLine[k] = ' ';
      if( i+j<n ){
        unsigned char c = x[i+j];
        zLine[k+1] = zHex[c>>4];
        zLine[k+2] = zHex[c&0xf];
      }else{
        zLine[k+1] = ' ';
        zLine[k+2] = ' ';
      }
    }
    zLine[53] = ' ';
    zLine[54] = ' ';
    for(j=0; j<16; j++){
      k = j+55;
      if( i+j<n ){
        unsigned char c = x[i+j];
        if( c>=0x20 && c<=0x7e ){
          zLine[k] = c;
        }else{
          zLine[k] = '.';
        }
      }else{
        zLine[k] = 0;
      }
    }
    zLine[71] = 0;
    @ %h(zLine)
  }
}

/*
** WEBPAGE: hexdump
** URL: /hexdump?name=ARTIFACTID
** 
** Show the complete content of a file identified by ARTIFACTID
** as preformatted text.
*/
void hexdump_page(void){
  int rid;
  Blob content;

  rid = name_to_rid(PD("name","0"));
  login_check_credentials();
  if( !g.okRead ){ login_needed(); return; }
  if( rid==0 ){ cgi_redirect("/home"); }
  if( g.okAdmin ){
    const char *zUuid = db_text("", "SELECT uuid FROM blob WHERE rid=%d", rid);
    if( db_exists("SELECT 1 FROM shun WHERE uuid='%s'", zUuid) ){
      style_submenu_element("Unshun","Unshun", "%s/shun?uuid=%s&sub=1",
            g.zTop, zUuid);
    }else{
      style_submenu_element("Shun","Shun", "%s/shun?shun=%s#addshun",
            g.zTop, zUuid);
    }
  }
  style_header("Hex Artifact Content");
  @ <h2>Hexadecimal Content Of:</h2>
  @ <blockquote>
  object_description(rid, 0);
  @ </blockquote>
  @ <hr>
  content_get(rid, &content);
  @ <blockquote><pre>
  hexdump(&content);
  @ </pre></blockquote>
  style_footer();
}

/*
** WEBPAGE: artifact
** URL: /artifact?name=ARTIFACTID
** 
** Show the complete content of a file identified by ARTIFACTID
** as preformatted text.

      style_submenu_element("Shun","Shun", "%s/shun?shun=%s#addshun",
            g.zTop, zUuid);
    }
  }
  style_header("Artifact Content");
  @ <h2>Content Of:</h2>
  @ <blockquote>
  object_description(rid, 0);
  @ </blockquote>
  @ <hr>
  @ <blockquote>
  content_get(rid, &content);
  zMime = mimetype_from_content(&content);
  if( zMime==0 ){
    @ <pre>
    @ %h(blob_str(&content))
    @ </pre>
    style_submenu_element("Hex","Hex", "%s/hexdump?name=%d", g.zTop, rid);
  }else if( strncmp(zMime, "image/", 6)==0 ){
    @ <img src="%s(g.zBaseURL)/raw?name=%d(rid)&m=%s(zMime)"></img>
    style_submenu_element("Hex","Hex", "%s/hexdump?name=%d", g.zTop, rid);
  }else{
    @ <pre>

    hexdump(&content);
    @ </pre>

  }
  @ </blockquote>
  style_footer();
}

/*
** WEBPAGE: tinfo
** URL: /tinfo?name=ARTIFACTID
**