#!/usr/bin/python3
"""
Tree inputs

Open the tree produced by the pipeline supplied via the
first and only entry in `references`. The tree is opened
in read only mode. If the id is `null` or the empty
string it returns an empty tree.
"""


import json
import sys

from osbuild.objectstore import StoreClient


SCHEMA = """
"additionalProperties": false,
"required": ["type", "origin", "references"],
"properties": {
  "type": {
    "enum": ["org.osbuild.tree"]
  },
  "origin": {
    "description": "The origin of the input (must be 'org.osbuild.pipeline')",
    "type": "string",
    "enum": ["org.osbuild.pipeline"]
  },
  "references": {
    "description": "Exactly one pipeline identifier to ues as tree input",
    "oneOf": [{
      "type": "array",
      "additionalItems": false,
      "items": [{
        "type": "string"
      }]
    }, {
      "type": "object",
      "additionalProperties": false,
      "patternProperties": {
         ".*": {
           "type": "object",
           "additionalProperties": false
         }
       },
       "minProperties": 1,
       "maxProperties": 1
    }]
  }
}
"""


def error(msg):
    json.dump({"error": msg}, sys.stdout)
    sys.exit(1)


def main():
    args = json.load(sys.stdin)
    refs = args["refs"]

    # input verification *must* have been done via schema
    # verification. It is expected that origin is a pipeline
    # and we have exactly one reference, i.e. a pipeline id
    pid, _ = refs.popitem()

    store = StoreClient(connect_to=args["api"]["store"])

    if not pid:
        path = store.mkdtemp(prefix="empty")
    else:
        path = store.read_tree(pid)

    if not path:
        error(f"Could not find pipeline with id '{pid}'")

    json.dump({"path": path}, sys.stdout)
    return 0


if __name__ == '__main__':
    r = main()
    sys.exit(r)