COSQLiteStore+Graphviz.m

/*
    Copyright (C) 2013 Eric Wasylishen

    Date:  November 2013
    License:  MIT  (see COPYING)
 */

#import "COSQLiteStore+Graphviz.h"
#import "COSQLiteStore+Private.h"
#import "COSQLiteStorePersistentRootBackingStore.h"
#import "CORevisionInfo.h"
#import "COPersistentRootInfo.h"
#import "COBranchInfo.h"
#import "COJSONSerialization.h"
#import <AppKit/AppKit.h>

@implementation COSQLiteStore (Debugging)

- (NSString *)dotNameForRevisionUUID: (ETUUID *)aUUID
{
    NSString *str = [aUUID stringValue];
    str = [str stringByReplacingOccurrencesOfString: @"-" withString: @"_"];

    return [@"rev_" stringByAppendingString: str];
}

- (NSString *)dotNameForBranchUUID: (ETUUID *)aUUID
{
    NSString *str = [aUUID stringValue];
    str = [str stringByReplacingOccurrencesOfString: @"-" withString: @"_"];

    return [@"branch_" stringByAppendingString: str];
}

- (NSString *)labelForMetadata: (NSDictionary *)metadata
{
    NSString *escapedMetadata = [[NSString alloc] initWithData: CODataWithJSONObject(metadata, NULL)
                                                      encoding: NSUTF8StringEncoding];
    // FIXME: escape escapedMetadata
    return escapedMetadata;
}

- (void)writeDotNodeForRevisionInfo: (CORevisionInfo *)revInfo toString: (NSMutableString *)dest
{
    if (revInfo.mergeParentRevisionUUID != nil)
    {
        [dest appendFormat: @" %@ -> %@ [color=orange];\n",
                            [self dotNameForRevisionUUID: revInfo.mergeParentRevisionUUID],
                            [self dotNameForRevisionUUID: revInfo.revisionUUID]];
        [dest appendFormat: @" %@ -> %@;\n",
                            [self dotNameForRevisionUUID: revInfo.parentRevisionUUID],
                            [self dotNameForRevisionUUID: revInfo.revisionUUID]];
    }
    else if (revInfo.parentRevisionUUID != nil)
    {
        [dest appendFormat: @" %@ -> %@;\n",
                            [self dotNameForRevisionUUID: revInfo.parentRevisionUUID],
                            [self dotNameForRevisionUUID: revInfo.revisionUUID]];
    }
    else
    {
        [dest appendFormat: @" %@;\n", [self dotNameForRevisionUUID: revInfo.revisionUUID]];
    }

    if (revInfo.metadata != nil)
    {
        [dest appendFormat: @" %@ -> %@_metadata [style=dotted,label=\"metadata\"];\n",
                            [self dotNameForRevisionUUID: revInfo.revisionUUID],
                            [self dotNameForRevisionUUID: revInfo.revisionUUID]];

        NSString *escapedMetadata = [self labelForMetadata: revInfo.metadata];

        [dest appendFormat: @" %@_metadata [shape=box,color=red,label=<%@>];\n",
                            [self dotNameForRevisionUUID: revInfo.revisionUUID],
                            escapedMetadata];
    }
}

- (NSString *)dotGraphForPersistentRootUUID: (ETUUID *)aPersistentRoot
{
    NSMutableString *result = [NSMutableString string];

    COPersistentRootInfo *info = [self persistentRootInfoForUUID: aPersistentRoot];

    assert(dispatch_get_current_queue() != queue_);

    dispatch_sync(queue_, ^()
    {
        COSQLiteStorePersistentRootBackingStore *backing = [self backingStoreForPersistentRootUUID: aPersistentRoot
                                                                                createIfNotPresent: YES];

        [result appendString: @"digraph G {\n"];

        // Add revisions

        NSIndexSet *revidsUsed = backing.revidsUsedRange;
        for (NSUInteger i = revidsUsed.firstIndex; i != NSNotFound; i = [revidsUsed indexGreaterThanIndex: i])
        {
            ETUUID *revUUID = [backing revisionUUIDForRevid: i];
            if (revUUID != nil)
            {
                CORevisionInfo *revInfo = [backing revisionInfoForRevisionUUID: revUUID];
                [self writeDotNodeForRevisionInfo: revInfo toString: result];
            }
        }

        // Add branches

        for (ETUUID *branchUUID in info.branchUUIDs)
        {
            COBranchInfo *branchInfo = [info branchInfoForUUID: branchUUID];

            if ([branchInfo.headRevisionUUID isEqual: branchInfo.currentRevisionUUID])
            {
                [result appendFormat: @" %@ -> %@ [style=dotted];\n",
                                      [self dotNameForBranchUUID: branchInfo.UUID],
                                      [self dotNameForRevisionUUID: branchInfo.headRevisionUUID]];
            }
            else
            {
                [result appendFormat: @" %@ -> %@ [style=dotted,label=\"head\"];\n",
                                      [self dotNameForBranchUUID: branchInfo.UUID],
                                      [self dotNameForRevisionUUID: branchInfo.headRevisionUUID]];

                [result appendFormat: @" %@ -> %@ [style=dotted,label=\"current\"];\n",
                                      [self dotNameForBranchUUID: branchInfo.UUID],
                                      [self dotNameForRevisionUUID: branchInfo.currentRevisionUUID]];
            }

            if (branchInfo.metadata != nil)
            {
                [result appendFormat: @" %@ -> %@_metadata [style=dotted,label=\"metadata\"];\n",
                                      [self dotNameForBranchUUID: branchInfo.UUID],
                                      [self dotNameForBranchUUID: branchInfo.UUID]];

                NSString *escapedMetadata = [self labelForMetadata: branchInfo.metadata];
                // FIXME: escape escapedMetadata

                [result appendFormat: @" %@_metadata [shape=box,color=red,label=<%@>];\n",
                                      [self dotNameForBranchUUID: branchInfo.UUID],
                                      escapedMetadata];
            }

            [result appendFormat: @" %@ [shape=box];\n",
                                  [self dotNameForBranchUUID: branchInfo.UUID]];
        }

        [result appendString: @"}\n"];

    });

    return result;
}

- (void)showGraphForPersistentRootUUID: (ETUUID *)aUUID
{
    NSString *basePath = [NSString stringWithFormat: @"%@-%d",
                                                     [NSTemporaryDirectory() stringByAppendingPathComponent: [aUUID stringValue]],
                                                     rand()];

    NSString *dotGraphPath = [basePath stringByAppendingPathExtension: @"gv"];

    [[self dotGraphForPersistentRootUUID: aUUID] writeToFile: dotGraphPath
                                                  atomically: YES
                                                    encoding: NSUTF8StringEncoding
                                                       error: NULL];

    COViewDOTGraphFile(dotGraphPath);
}

void COViewDOTGraphFile(NSString *dotFilePath)
{
    NSString *pdfPath = [dotFilePath stringByAppendingPathExtension: @"pdf"];

    for (NSString *executablePath in @[@"/usr/bin/dot", @"/usr/local/bin/dot"])
    {
        if (![[NSFileManager defaultManager] fileExistsAtPath: executablePath])
        {
            continue;
        }

        NSTask *task = [NSTask launchedTaskWithLaunchPath: executablePath
                                                arguments: @[@"-Tpdf", dotFilePath, @"-o", pdfPath]];
        [task waitUntilExit];
        [[NSWorkspace sharedWorkspace] openFile: pdfPath];
        break;
    }
}

@end