forked from asteris-llc/converge
-
Notifications
You must be signed in to change notification settings - Fork 0
/
prettyprinter.go
135 lines (114 loc) · 3.09 KB
/
prettyprinter.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
// Copyright © 2016 Asteris, LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package prettyprinters
import (
"bytes"
"context"
"github.com/asteris-llc/converge/graph"
)
// New creates a new prettyprinter instance from the specified
// DigraphPrettyPrinter instance.
func New(p BasePrinter) Printer {
return Printer{pp: p}
}
// Show will take the given graph and return a string representing the text
// output of the graph according to the associated prettyprinter. If an error
// is returned at any stage of the prettyprinting process it is returned
// unmodified to the user.
func (p Printer) Show(ctx context.Context, g *graph.Graph) (string, error) {
outputBuffer := new(bytes.Buffer)
write := func(s Renderable) { outputBuffer.WriteString(s.String()) }
subgraphs := makeSubgraphMap()
p.loadSubgraphs(ctx, g, subgraphs)
rootNodes := subgraphs[nil].Nodes
graphPrinter, gpOK := p.pp.(GraphPrinter)
if gpOK {
if str, err := graphPrinter.StartPP(g); err == nil {
outputBuffer.WriteString(str.String())
} else {
return "", err
}
}
nodePrinter, npOK := p.pp.(NodePrinter)
if npOK {
for _, node := range rootNodes {
if str, err := nodePrinter.DrawNode(g, node); err == nil {
write(str)
} else {
return "", err
}
}
}
for graphID, graph := range subgraphs {
if graphID == SubgraphBottomID {
continue
}
if str, err := p.drawSubgraph(g, graphID, graph); err == nil {
write(str)
} else {
return "", err
}
}
if str, err := p.drawEdges(g); err == nil {
write(str)
} else {
return "", err
}
if gpOK {
if str, err := graphPrinter.FinishPP(g); err == nil {
write(str)
} else {
return "", err
}
}
return outputBuffer.String(), nil
}
func (p Printer) drawEdges(g *graph.Graph) (Renderable, error) {
edgePrinter, epOK := p.pp.(EdgePrinter)
edgeSectionPrinter, espOK := p.pp.(EdgeSectionPrinter)
if !epOK && !espOK {
return HiddenString(), nil
}
outputBuffer := new(bytes.Buffer)
write := func(s Renderable) { outputBuffer.WriteString(s.String()) }
edges := g.Edges()
if espOK {
if str, err := edgeSectionPrinter.StartEdgeSection(g); err == nil {
write(str)
} else {
return nil, err
}
}
if epOK {
for _, edge := range edges {
if str, err := edgePrinter.DrawEdge(g, edge.Source, edge.Dest); err == nil {
write(str)
} else {
return nil, err
}
}
}
if espOK {
if str, err := edgeSectionPrinter.FinishEdgeSection(g); err == nil {
write(str)
} else {
return nil, err
}
}
return outputBuffer, nil
}
// Printer is the top-level structure for a pretty printer.
type Printer struct {
pp BasePrinter
}