1 files changed, 102 insertions, 0 deletions
diff --git a/ick2/buildgraph.py b/ick2/buildgraph.py
new file mode 100644
index 0000000..ddcfbfb
--- /dev/null
+++ b/ick2/buildgraph.py
@@ -0,0 +1,102 @@
+# Copyright (C) 2018  Lars Wirzenius
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+import copy
+
+
+class BuildGraph:
+
+    def __init__(self, graph=None):
+        self.observer = None
+        self.actions = graph or {}
+        self.idgen = IdGenerator(self.actions.keys())
+
+    def set_observer(self, observer):
+        self.observer = observer
+
+    def get_actions(self):
+        return copy.deepcopy(self.actions)
+
+    def get_action(self, action_id):
+        return self.actions[action_id]['action']
+
+    def get_action_status(self, action_id):
+        return self.actions[action_id]['status']
+
+    def set_action_status(self, action_id, status):
+        self.actions[action_id]['status'] = status
+        self.trigger_observer()
+
+    def unblock(self):
+        blocked_ids = self.find_actions('blocked')
+        for blocked_id in blocked_ids:
+            blocked = self.actions[blocked_id]
+            if self.is_unblockable(blocked):
+                self.set_action_status(blocked_id, 'ready')
+
+    def is_unblockable(self, action):
+        return all(
+            self.get_action_status(dep) == 'done'
+            for dep in action['depends']
+        )
+
+    def trigger_observer(self):
+        if self.observer is not None:
+            self.observer()
+
+    def append_action(self, action):
+        prev_id, action_id = self.idgen.next_id()
+
+        graph_node = {
+            'action': copy.deepcopy(action),
+        }
+
+        if not self.actions:
+            graph_node['status'] = 'ready'
+            graph_node['depends'] = []
+        else:
+            graph_node['status'] = 'blocked'
+            graph_node['depends'] = [prev_id]
+
+        self.actions[action_id] = graph_node
+        self.trigger_observer()
+        return action_id
+
+    def append_pipeline(self, pipeline):
+        for action in pipeline.get('actions', []):
+            self.append_action(action)
+
+    def find_actions(self, status):
+        return [
+            action_id
+            for action_id, action in self.actions.items()
+            if action['status'] == status
+        ]
+
+
+class IdGenerator:
+
+    def __init__(self, action_ids):
+        self.current = 0
+        if action_ids:
+            action_ids = [int(an_id) for an_id in action_ids]
+            action_ids.sort()
+            self.current = action_ids[-1]
+
+    def next_id(self):
+        prev = self.current
+        self.current += 1
+        return str(prev), str(self.current)