#!/usr/bin/env xcrun swift


import Cocoa


class Task {
    class func execute(name: String) -> String {
        let task = NSTask()
        task.launchPath = "/bin/sh"
        task.arguments = ["-c", name]

        let pipe = NSPipe()
        task.standardOutput = pipe

        let file = pipe.fileHandleForReading

        task.launch()

        let data = file.readDataToEndOfFile()
        let result = NSString(data: data, encoding: NSUTF8StringEncoding)


        return result as! String
    }
}

struct Committer {
    let name : String
    let lines : Int
}

struct Commit {
    let filePath : String
    let committers : [Committer]

    func toString() -> String {
        var result = "File: \(self.filePath)\n"
        let sortedCommitters = committers.sort{$0.lines > $1.lines}
        for committer in sortedCommitters {
            result += "\t- \(committer.name) (\(committer.lines))\n"
        }

        return result
    }
}

class GitCommand {
    private class func changedFiles() -> [String] {
        let fileChangedCmd = "git --no-pager diff --name-only FETCH_HEAD $(git merge-base FETCH_HEAD master)"
        let filesString = Task.execute(fileChangedCmd)
        let files = (filesString as NSString).componentsSeparatedByString("\n");

        return files
    }

    private class func blameFile(file: String) -> Commit? {

        if file.lengthOfBytesUsingEncoding(NSUTF8StringEncoding) == 0 {
            return nil
        }

        let blameCmd = "git blame \(file) | awk '{print $2,$3}'"
        let blameResult = Task.execute(blameCmd)
        let lines = (blameResult as NSString).componentsSeparatedByString("\n")
        var committers = [String : Int]()
        for var user in lines {
            if user.lengthOfBytesUsingEncoding(NSUTF8StringEncoding) == 0 {
                continue
            }
            if user.hasPrefix("(") {
                user = user.substringFromIndex(user.startIndex.advancedBy(1))
            }

            let count = committers[user]
            committers[user] = (count != nil) ? (count! + 1) : 1
        }

        let realCommitters = committers.map{return Committer(name: $0, lines: $1)}

        let commit = Commit(filePath: file, committers: realCommitters)
        return commit
    }


    class func allUsersInCommit() {
        let files = self.changedFiles()
        for file in files {
            if !file.hasPrefix("Resource") {
                if let commit = self.blameFile(file) {
                    print(commit.toString())
                }
            }
        }
    }
}


print("\n\n### Current Brach Files ###")
GitCommand.allUsersInCommit()