#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#else
#include <io.h>
#endif
#include "Input.h"
#include "Exceptions.h"
#include "gettext.h"

#ifndef S_ISREG
#define S_ISREG(x) 1
#endif

#define BUILTIN_SIG 0x5141504e

static Input::openresults_t gresults;

Input::Input(const String & no) throw (GeneralException) :
    Handle(no.strlen() ? wrapopen(no, &gresults) : dup(0)),
    n(no) {

#ifdef DEBUG    
    fprintf(stderr, "Opening file %s, Input at %p\n", no.to_charp(), this);
#endif

    if (GetHandle() < 0) {
	throw IOGeneral(String(_("Error opening file ")) + no + _(" for reading: ") + strerror(errno));
    }
    
    results = gresults;
    
    fromarchive = false;
    if (results.name == "") {
	struct stat s;
	fstat(GetHandle(), &s);
	date_modif = s.st_mtime;

	if (S_ISREG(s.st_mode)) {
	    size = seek(0, SEEK_END);
	    seek(0, SEEK_SET);
	}
    } else {
//	size = results.size;
	seek(results.ptr, SEEK_SET);
	read(&size, 4);
	date_modif = 0;
	SetZ();
	fromarchive = true;
    }
}

Input::Input(const Input & i) : Handle(i), n(i.n), size(i.size), date_modif(i.date_modif) {
}

bool Input::CanWrite() const {
    return 0;
}

bool Input::CanRead() const {
    return 1;
}

bool Input::CanSeek() const {
    struct stat s;
    
    fstat(GetHandle(), &s);

    return S_ISREG(s.st_mode);
}

String Input::GetName() const {
    return n;
}

ssize_t Input::GetSize() const {
    return size;
}

time_t Input::GetModif() const {
    return date_modif;
}

off_t Input::seek(off_t offset, int whence) throw (GeneralException) {
    if (!fromarchive) {
	if ((itell = lseek(GetHandle(), offset, whence)) < 0) {
	    throw IOGeneral(String(_("Error seeking file ")) + GetName() + _(": ") + strerror(errno));
	}
#ifdef PARANOID_SEEK
	if (itell != lseek(GetHandle(), 0, SEEK_CUR)) {
	    throw IOGeneral(String(_("Error seeking file ")) + GetName() + _(": the position does not match"));
	}
#endif
	return itell;
    } else {
	return Handle::seek(offset, whence);
    }
}

int Input::wrapopen(const String & fname, openresults_t * results) {
#ifdef DEBUG
    std::cerr << "Wrap-opening " << fname << std::endl;
#endif
    if (fname[0] != '/') {
	bool t;
	t = Archive::inarchive(fname);
	if (t) {
#ifdef DEBUG
	    std::cerr << "Trying to open the file in archive, since it seems to be here\n";
#endif
	    return Archive::open(fname, results);
	}
    }
    return open(fname.to_charp(), O_RDONLY);
}

void Input::SetZ(int l) throw(GeneralException) {
    if (!fromarchive)
	Handle::SetZ(l);
}

Stdin_t::Stdin_t() { }

bool Stdin_t::CanSeek() const {
    return 0;
}

String Stdin_t::GetName() const {
    return "Stdin";
}

#ifdef HOOK_STDS
Stdin_t Stdin;
#endif

Archive * Archive::header = 0;

Archive::Archive(const String & fname, int atype) throw (GeneralException) :
  name(fname), archive(fname), type(atype) {
    char buffer[1024];
    int len;
    size_t size;
    FileTree * p = &filetree, * t;
    String ifname;

    switch(type) {
    case ARCHIVE_BUILTIN:
	archive.read(buffer, 4);
	if (*((Uint32 *)buffer) != BUILTIN_SIG)
	    throw GeneralException("Archive: not in built-in format.");
	while (p) {
	    archive.read(buffer, 1);
	    len = *buffer;
	    if (len) {
		archive.read(buffer, len);
		buffer[len] = 0;
		ifname = buffer;
		archive.read(&size, 4);
		archive.read(buffer, 1);
#ifdef DEBUG
		std::cerr << "Adding file `" << ifname << "' to node `" << p->name << "'\n";
#endif
		t = new FileTree(ifname, size, buffer[0], p);
		if (buffer[0])
		    p = t;
	    } else {
		p = p->Father();
	    }
	}
	filetree.compute_ptrs(archive.tell());
	break;
    default:
	throw GeneralException("Archive: unsupported archive format.");
    }

    next = header;
    prev = 0;
    header = this;
    if (next)
	next->prev = this;

}

Archive::~Archive() {
    if (prev)
	prev->next = next;
    if (next)
	next->prev = prev;
    if (header == this)
	header = next;
}

bool Archive::inarchive(const String & fname) {
    Archive * p;
    for (p = header; p; p = p->next) {
#ifdef DEBUG
	std::cerr << "Looking for file `" << fname << "' in archive " << p->name << std::endl;
#endif
	if (p->inarchivein(fname)) {
#ifdef DEBUG
	    std::cerr << "File `" << fname << "' found in archive " << p->name << std::endl;
#endif
	    return true;
	}
    }
    return false;
}

int Archive::open(const String & fname, Input::openresults_t * results) throw (GeneralException) {
    Archive * p;

    for (p = header; p; p = p->next) {
	bool t;
	t = p->inarchive(fname);
	if (t)
	    return p->openin(fname, results);
    }
    throw IOGeneral("File `" + fname + "' not found in archive collection.");
}

bool Archive::inarchivein(const String & fname) {
    Archive::FileTree * p = filetree.Child();
    ssize_t pos;
    String name = fname;
    String reste;
    
    while((name != "") && p) {
	pos = name.strchr('/');
	if (pos >= 0) {
	    reste = name.extract(0, pos - 1);
	    name = name.extract(pos + 1);
	} else {
	    reste = name;
	    name = "";
	}
#ifdef DEBUG
	std::cerr << "inarchivein: reste = `" << reste << "' - name = `" << name << "'\n";
	std::cerr << "Checking against node `" << p->name << "'\n";
#endif
	while (p) {
	    if (p->name == reste) {
		if (name != "")
		    p = p->Child();
		break;
	    } else {
		p = p->Next();
	    }
	}
    }
    
    return p;
}

int Archive::openin(const String & fname, Input::openresults_t * results) throw (GeneralException) {
    Archive::FileTree * p = filetree.Child();
    ssize_t pos;
    String name = fname;
    String reste;
    
    while((name != "") && p) {
	pos = name.strchr('/');
	if (pos >= 0) {
	    reste = name.extract(0, pos - 1);
	    name = name.extract(pos + 1);
	} else {
	    reste = name;
	    name = "";
	}
	
	while (p) {
	    if (p->name == reste) {
		if (name != "")
		    p = p->Child();
		break;
	    } else {
		p = p->Next();
	    }
	}
    }
    
    if (!p)
	throw IOGeneral("File `" + fname + "' not in archive " + this->name);
    
    if (p->Child())
	throw IOGeneral("File `" + fname + "' in archive " + this->name + " is a directory - can't open.");

    results->name = p->name;
    results->ptr = p->ptr;
    results->size = p->size;
    results->type = p->type;
    return archive.Dup();
}

Archive::FileTree::FileTree(const String & fname, size_t fsize, int ftype, Archive::FileTree * fFather) :
  name(fname), type(ftype), size(fsize), next(0), prev(0), father(fFather), child(0) {
    if (father) {
	if (father->child) {
	    FileTree * p;
	    for (p = father->child; p->next; p = p->next);
	    p->next = this;
	    prev = p;
	} else {
#ifdef DEBUG
	    std::cerr << "Adding `" << fname << "' as first child of node `" << father->name << "'\n";
#endif
	    father->child = this;
	}
    }
}

Archive::FileTree::~FileTree() {
    if (child)
	delete child;
    if (next)
	next->prev = prev;
    if (prev)
	prev->next = next;
    if (father) {
	if (father->child == this)
	    father->child = next;
	father->touched();
    }
}

void Archive::FileTree::touched() {
    if (father)
	father->touched();
    else
	compute_ptrs(ptr);
}

int Archive::FileTree::compute_ptrs(size_t cptr) {
    ptr = cptr;
    
    if (child) {
	FileTree * p;
	size = 0;
	for (p = child; p; p = p->next) {
	    size += p->compute_ptrs(ptr + size) - ptr;
	}
    }
    
    return size + ptr;
}

Archive::FileTree * Archive::FileTree::Father() {
    return father;
}

Archive::FileTree * Archive::FileTree::Child() {
    return child;
}

Archive::FileTree * Archive::FileTree::Next() {
    return next;
}

Archive::FileTree * Archive::FileTree::Prev() {
    return prev;
}