/+
- Name: SisuDoc Spine, Doc Reform [a part of]
  - Description: documents, structuring, processing, publishing, search
    - static content generator

  - Author: Ralph Amissah
    [ralph.amissah@gmail.com]

  - Copyright: (C) 2015 (continuously updated, current 2026) Ralph Amissah, All Rights Reserved.

  - License: AGPL 3 or later:

    Spine (SiSU), a framework for document structuring, publishing and
    search

    Copyright (C) Ralph Amissah

    This program is free software: you can redistribute it and/or modify it
    under the terms of the GNU AFERO General Public License as published by the
    Free Software Foundation, either version 3 of the License, or (at your
    option) any later version.

    This program is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
    more details.

    You should have received a copy of the GNU General Public License along with
    this program. If not, see [https://www.gnu.org/licenses/].

    If you have Internet connection, the latest version of the AGPL should be
    available at these locations:
    [https://www.fsf.org/licensing/licenses/agpl.html]
    [https://www.gnu.org/licenses/agpl.html]

  - Spine (by Doc Reform, related to SiSU) uses standard:
    - docReform markup syntax
      - standard SiSU markup syntax with modified headers and minor modifications
    - docReform object numbering
      - standard SiSU object citation numbering & system

  - Homepages:
    [https://www.sisudoc.org]
    [https://www.doc-reform.org]

  - Git
    [https://git.sisudoc.org/]

+/
module ocda.load;

/+ ↓ what a path is, and loading it.
     .
     One place that decides, so that every reader and every writer accepts
     the same inputs and a new input type is added once. This mirrors
     spine's own ocda/abstraction/load.d, which names the sources it can
     enter the pipeline from and tells them apart by suffix.
     .
     Deliberately *not* here: .sst and .ssm markup. Reading markup means
     implementing the parser, which is spine's work and a far larger thing
     than a reader or a sample writer needs. This library reads
     abstractions.
+/

import std.algorithm : endsWith;
import ocda.model;
import ocda.load_ssp;
import ocda.load_db;
import ocda.load_pod;

enum Source {
  ssp,        // .ssp, the abstraction as text
  ocda_db,    // .ocda.db, the abstraction as sqlite
  pod,        // .sisupod or .zip, an archive carrying a .ssp
  unknown,
}

Source sourceOf(string path) {
  if (path.endsWith(".ocda.db")) { return Source.ocda_db; }
  if (path.endsWith(".ssp"))     { return Source.ssp; }
  /+ ↓ .sisupod is the archive spine writes now; .zip is what it wrote
       before, and every pod already published carries that name, so both
       are read. What is inside decides how it is opened, not the name.
  +/
  if (path.endsWith(".sisupod"))  { return Source.pod; }
  if (path.endsWith(".zip"))      { return Source.pod; }
  if (path.endsWith(".db"))      { return Source.ocda_db; }
  return Source.unknown;
}

string sourceName(Source s) {
  final switch (s) {
  case Source.ssp:     return ".ssp (the abstraction as text)";
  case Source.ocda_db: return ".ocda.db (the abstraction as sqlite)";
  case Source.pod:     return "a pod archive carrying a .ssp";
  case Source.unknown: return "not an abstraction this library reads";
  }
}

class OcdaLoadError : Exception {
  this(string msg) { super(msg); }
}

/+ ↓ load whatever the path is into the model.
     lang names which language to take from a .ocda.db, which holds
     every language of its document, and from a pod, which may carry more
     than one .ssp. A .ssp is one language by construction and ignores it.
+/
OcdaDocument load(string path, string lang = "", bool any_version = false) {
  final switch (sourceOf(path)) {
  case Source.ssp:     return parseSspFile(path);
  case Source.ocda_db: return loadDbFile(path, lang, any_version);
  case Source.pod:     return loadPodFile(path, lang);
  case Source.unknown:
    throw new OcdaLoadError(path ~ ": " ~ sourceName(Source.unknown)
      ~ " (expected .ssp, .ocda.db, .sisupod or .zip)");
  }
}