#!/usr/bin/env r
## DOC: cran2deb license
## DOC:     add licenses and change acceptance/rejection of licenses
## DOC:

suppressPackageStartupMessages(library(cran2deb))
suppressPackageStartupMessages(library(digest))

exec_cmd <- function(argc, argv) {
    usage <- function()
        message(paste('usage: accept <license>'
                     ,'       reject <license>'
                     ,'       hash <license> (<path>|<hash>)'
                     ,'       pkg <license> <pkg>'
                     ,'       view <pkg>'
                     ,'       ls'
                     ,'       quit'
                     ,sep='\n'))

    if (argc < 1) {
        exit()
    }
    cmd = argv[1]

    if (cmd == 'accept' || cmd == 'reject') {
        if (argc != 2) {
            usage()
            return()
        }
        action = (cmd == 'accept')
        db_add_license_override(argv[2],action)
    } else if (cmd == 'hash') {
        if (argc != 3) {
            usage()
            return()
        }
        license = argv[2]
        path = argv[3]
        if (is.null(db_license_override_name(license))) {
            error('license',license,'is not known; add it first')
            return()
        }
        if (file.exists(path)) {
            license_sha1 = digest(readChar(path,file.info(path)$size)
                                 ,algo='sha1', serialize=FALSE)
        } else if (length(grep('^[0-9a-f]{40}$',path))) {
            license_sha1 = path
        } else {
            error(path,'does not exist and does not look like an SHA1 hash')
            return()
        }
        db_add_license_hash(license,license_sha1)
    } else if (cmd == 'pkg') {
        if (argc != 3) {
            usage()
            return()
        }
        license <- argv[2]
        pkg_name <- argv[3]
        current_action <- db_license_override_name(license)
        if (is.null(current_action)) {
            notice('license',license,'is not known; add it')
            return()
        }
        action = 'accept'
        if (!current_action) {
            action = 'reject'
        }
        notice('in future, will',action,'the package',pkg_name,'under license',license)
        tmp <- setup()
        success <- try((function() {
            pkg <- prepare_pkg(tmp,pkg_name)
            if (!('License' %in% names(pkg$description[1,]))) {
                error('package',pkg$name,'has no License: field in DESCRIPTION')
                return()
            }
            first_license = (strsplit(chomp(pkg$description[1,'License'])
                                     ,'[[:space:]]*\\|[[:space:]]*')[[1]])[1]
            license_sha1 <- get_license_hash(pkg,first_license)
            db_add_license_hash(license,license_sha1)
        })())
        cleanup(tmp)
        if (inherits(success,'try-error')) {
            return()
        }
    } else if (cmd == 'view') {
        if (argc != 2) {
            usage()
            return()
        }
        pkg_name <- argv[2]
        tmp <- setup()
        success <- try((function() {
            pkg <- prepare_pkg(tmp,pkg_name)
            if (!('License' %in% names(pkg$description[1,]))) {
                error('package',pkg$name,'has no License: field in DESCRIPTION')
                return()
            }
            first_license = (strsplit(chomp(pkg$description[1,'License'])
                                     ,'[[:space:]]*\\|[[:space:]]*')[[1]])[1]
            first_license = get_license(pkg,first_license)
            cat(strwrap(first_license),file='|less')
        })())
        cleanup(tmp)
        if (inherits(success,'try-error')) {
            return()
        }
    } else if (cmd == 'ls') {
        for (x in db_license_overrides()) print(x)
    } else if (cmd == 'help') {
        usage()
        return()
    } else if (cmd == 'quit') {
        exit()
    }
}

argc <- length(argv)
if (argc > 1) {
    exec_cmd(argc-1,argv[c(2:argc)])
} else {
    while(T) {
        argv <- strsplit(readline('license> '),'[[:space:]]+')[[1]]
        exec_cmd(length(argv),argv)
    }
}