// file      : bpkg/manifest -*- C++ -*-
// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
// license   : MIT; see accompanying LICENSE file

#ifndef BPKG_MANIFEST
#define BPKG_MANIFEST

#include <string>
#include <vector>
#include <cstdint>   // uint16_t
#include <ostream>
#include <algorithm> // move()
#include <stdexcept> // logic_error

#include <butl/path>
#include <butl/optional>

namespace bpkg
{
  class manifest_parser;
  class manifest_serializer;
  class manifest_name_value;

  using strings = std::vector<std::string>;

  class version
  {
  public:
    // Create a special empty version.
    //
    version (): epoch_ (0), revision_ (0) {}

    explicit
    version (const std::string& v): version (v.c_str ()) /* Delegate */ {}

    explicit
    version (const char* v): version (v, false) /* Delegate */ {}

    // Create the version object from separate epoch, upstream, and
    // revision parts.
    //
    version (std::uint16_t epoch,
             std::string upstream,
             std::uint16_t revision)
        : version (upstream.c_str (), true)  // Delegate

    {
      // Can't initialize in member initializer list due to construction
      // delegation.
      //
      epoch_ = epoch;
      revision_ = revision;
    }

    std::uint16_t
    epoch () const noexcept {return epoch_;}

    std::uint16_t
    revision () const noexcept {return revision_;}

    const std::string&
    upstream () const noexcept {return upstream_;}

    const std::string&
    canonical_upstream () const noexcept {return canonical_upstream_;}

    std::string
    string () const
    {
      const std::string& v (
        epoch_ != 0 ? std::to_string (epoch_) + "+" + upstream_ : upstream_);

      return revision_ != 0 ? v + "-" + std::to_string (revision_) : v;
    }

    bool
    operator< (const version& v) const noexcept {return compare (v) < 0;}

    bool
    operator> (const version& v) const noexcept {return compare (v) > 0;}

    bool
    operator== (const version& v) const noexcept {return compare (v) == 0;}

    bool
    operator<= (const version& v) const noexcept {return compare (v) <= 0;}

    bool
    operator>= (const version& v) const noexcept {return compare (v) >= 0;}

    bool
    operator!= (const version& v) const noexcept {return compare (v) != 0;}

    int
    compare (const version& v, bool ignore_revision = false) const noexcept
    {
      if (epoch_ != v.epoch_)
        return epoch_ < v.epoch_ ? -1 : 1;

      if (int c = canonical_upstream_.compare (v.canonical_upstream_))
        return c;

      if (!ignore_revision && revision_ != v.revision_)
        return revision_ < v.revision_ ? -1 : 1;

      return 0;
    }

    bool
    empty () const noexcept
    {
      // No sense to test epoch and revision for 0 as properly constructed
      // version object can not have them different from 0 if upstream is
      // empty. Returns true only for objects constructed with the default
      // constructor.
      //
      return upstream_.empty ();
    }

  private:
    version (const char*, bool upstream_only);

  private:
    // Let's keep the members in the order they appear in the string
    // representation.
    //
    std::uint16_t epoch_;
    std::string upstream_;
    std::uint16_t revision_;
    std::string canonical_upstream_; // Upstream part canonical representation.
  };

  inline std::ostream&
  operator<< (std::ostream& os, const version& v) {return os << v.string ();}

  // priority
  //
  class priority
  {
  public:
    enum value_type {low, medium, high, security};

    value_type value; // Shouldn't be necessary to access directly.
    std::string comment;

    priority (value_type v = low, std::string c = "")
        : value (v), comment (std::move (c)) {}

    operator value_type () const {return value;}
  };

  // description
  // description-file
  //
  class description: public std::string
  {
  public:
    bool file;
    std::string comment;

    // Description constructor.
    //
    explicit
    description (std::string d = "")
        : std::string (std::move (d)), file (false) {}

    // Description file constructor.
    //
    description (std::string f, std::string c)
        : std::string (std::move (f)), file (true), comment (std::move (c)) {}
  };

  // license
  //
  class licenses: public strings
  {
  public:
    std::string comment;

    explicit
    licenses (std::string c = ""): comment (std::move (c)) {}
  };

  // change
  // change-file
  //
  class change: public std::string
  {
  public:
    bool file;
    std::string comment;

    // Change constructor.
    //
    explicit
    change (std::string c = ""): std::string (std::move (c)), file (false) {}

    // Change file constructor.
    //
    change (std::string f, std::string c)
        : std::string (std::move (f)), file (true), comment (std::move (c)) {}
  };

  // url
  // package-url
  //
  class url: public std::string
  {
  public:
    std::string comment;

    explicit
    url (std::string u = "", std::string c = "")
        : std::string (std::move (u)), comment (std::move (c)) {}
  };

  // email
  // package-email
  //
  class email: public std::string
  {
  public:
    std::string comment;

    explicit
    email (std::string e = "", std::string c = "")
        : std::string (std::move (e)), comment (std::move (c)) {}
  };

  // depends
  //
  enum class comparison {eq, lt, gt, le, ge};

  struct version_comparison
  {
    version value;
    comparison operation;
  };

  struct dependency
  {
    std::string package;
    butl::optional<version_comparison> version;
  };

  class dependency_alternatives: public std::vector<dependency>
  {
  public:
    bool conditional;
    std::string comment;

    explicit
    dependency_alternatives (bool d = false, std::string c = "")
        : conditional (d), comment (std::move (c)) {}
  };

  // requires
  //
  class requirement_alternatives: public strings
  {
  public:
    bool conditional;
    std::string comment;

    explicit
    requirement_alternatives (bool d = false, std::string c = "")
        : conditional (d), comment (std::move (c)) {}
  };

  class package_manifest
  {
  public:
    using version_type = bpkg::version;
    using priority_type = bpkg::priority;
    using url_type = bpkg::url;
    using email_type = bpkg::email;
    using description_type = bpkg::description;

    std::string name;
    version_type version;
    butl::optional<priority_type> priority;
    std::string summary;
    std::vector<licenses> license_alternatives;
    strings tags;
    butl::optional<description_type> description;
    std::vector<change> changes;
    url_type url;
    butl::optional<url_type> package_url;
    email_type email;
    butl::optional<email_type> package_email;
    std::vector<dependency_alternatives> dependencies;
    std::vector<requirement_alternatives> requirements;

  public:
    package_manifest (manifest_parser&);
    package_manifest (manifest_parser&, manifest_name_value start);

    void
    serialize (manifest_serializer&) const;
  };

  class repository_location
  {
  public:
    // Create a special empty repository_location.
    //
    repository_location () = default;

    // Creates remote/absolute repository location. Throws invalid_argument
    // if the location is a relative path.
    //
    explicit
    repository_location (const std::string&);

    // Creates a potentially relative repository location. If base is not
    // empty, use it to complete the relative location to remote/absolute.
    // Throws invalid_argument if base itself is relative or the resulting
    // completed location is invalid.
    //
    repository_location (const std::string&, const repository_location& base);

    // Note that relative locations have no canonical name.
    //
    const std::string&
    canonical_name () const noexcept {return canonical_name_;}

    // There are 3 types of locations: remote, local absolute filesystem
    // path and local relative filesystem path. Plus there is the special
    // empty location. The following predicates can be used to determine
    // what kind of location it is. Note that except for empty(), all the
    // other predicates throw std::logic_error for an empty location.
    //
    bool
    empty () const noexcept {return path_.empty ();}

    bool
    local () const
    {
      if (empty ())
        throw std::logic_error ("empty location");

      return host_.empty ();
    }

    bool
    remote () const
    {
      return !local ();
    }

    bool
    absolute () const
    {
      return local () && path_.absolute ();
    }

    bool
    relative () const
    {
      if (empty ())
        throw std::logic_error ("empty location");

      // Note that in remote locations path is always absolute.
      //
      return path_.relative ();
    }

    const butl::dir_path&
    path () const
    {
      if (empty ())
        throw std::logic_error ("empty location");

      return path_;
    }

    const std::string&
    host () const
    {
      if (local ())
        throw std::logic_error ("local location");

      return host_;
    }

    // Value 0 indicated that no port was specified explicitly.
    //
    std::uint16_t
    port () const
    {
      if (local ())
        throw std::logic_error ("local location");

      return port_;
    }

    // Note that this is not necessarily syntactically the same
    // string as what was used to initialize this location. But
    // it should be semantically equivalent.
    //
    std::string
    string () const;

  private:
    std::string canonical_name_;
    std::string host_;
    std::uint16_t port_;
    butl::dir_path path_;
  };

  class repository_manifest
  {
  public:
    repository_location location;

  public:
    repository_manifest (manifest_parser&);
    repository_manifest (manifest_parser&, manifest_name_value start);

    void
    serialize (manifest_serializer&) const;
  };

  class manifests
  {
  public:
    std::vector<repository_manifest> repositories;
    std::vector<package_manifest> packages;

  public:
    manifests (manifest_parser&);

    void
    serialize (manifest_serializer&) const;
  };
}

#endif // BPKG_MANIFEST