import json
import os

def convert_to_iiif_v2(json_data):
    # Verifica se il file JSON è conforme a IIIF v3.0
    if "@context" not in json_data or json_data["@context"] != "http://iiif.io/api/presentation/3/context.json":
        print("Il file JSON fornito non è conforme a IIIF v3.0.")
        return None

    # Creazione di un nuovo oggetto IIIF v2.0
    iiif_v2_data = {
        "@context": "http://iiif.io/api/presentation/2/context.json",
        "@id": json_data["id"].replace("manifest","manifest2"),
        "@type": "sc:Manifest",
        "label": json_data.get("label", "")['it'][0],
        "sequences": [
            {
                "@id": json_data["id"] + "/sequence/s0",
                "@type": "sc:Sequence",
                "canvases": []
            }
        ]
    }

    # Conversione delle pagine
    for canvas in json_data.get("items", []):
        canvas_id = canvas["id"]
        canvas_label = canvas.get("label", "")

        iiif_v2_canvas = {
            "@id": canvas_id.split('/info.json')[0],
            "@type": "sc:Canvas",
            "label": canvas_label['it'][0],
            "width": canvas["width"],
            "height": canvas["height"],
            "images": [
                {
                    "@id": canvas_id.split('info.json')[0] + "full/max/0/default.jpg",
                    "@type": "oa:Annotation",
                    "motivation": "sc:painting",
                    "resource": {
                        "@id": canvas_id.split('info.json')[0] + "full/max/0/default.jpg",
                        "@type": "dctypes:Image",
                        "format": "image/jpeg",
                        "service": {
                            "@id": canvas_id.split('/info.json')[0].replace("8183/iiif/3/","8183/iiif/2/"),
                            "@context": "http://iiif.io/api/image/2/context.json",
                            "profile": "http://iiif.io/api/image/2/level1.json"
                        },
                        "height": canvas["height"],
                        "width": canvas["width"]
                    },
                    "on": canvas_id
                }
            ]
        }

        iiif_v2_data["sequences"][0]["canvases"].append(iiif_v2_canvas)

    return iiif_v2_data




def process_directory(directory):
    for root, dirs, files in os.walk(directory):
        for file in files:
            if file == "manifest.json":
                manifest_path = os.path.join(root, file)
                output_path = os.path.join(root, "manifest2.json")

                # Carica il file JSON IIIF v3.0
                with open(manifest_path, "r") as manifest_file:
                    json_data = json.load(manifest_file)

                # Converte in IIIF v2.0
                iiif_v2_data = convert_to_iiif_v2(json_data)

                if iiif_v2_data:
                    # Salva il risultato nel nuovo file JSON IIIF v2.0
                    with open(output_path, "w") as output_file:
                        json.dump(iiif_v2_data, output_file, indent=2)

                    print(f"Conversione completata per {manifest_path}. Il file IIIF v2.0 è stato salvato in: {output_path}")

def main():
    current_directory = os.getcwd()

    for entry in os.listdir(current_directory):
        if os.path.isdir(entry):
            process_directory(entry)

if __name__ == "__main__":
    main()