An crafty command-line interface to open the page viewer of the Asahi Shimbun.

asahi.ps1

<#

.SYNOPSIS
`asahi.ps1` : Open the latest issue, morning edition.
`asahi.ps1 ev` : Open the latest issue, evening edition.
`asahi.ps1 -issue 20180101 -edition ev` : Open the specified issue/edition.
`asahi.ps1 -duration -5 -edition ev` : Open the specified issue/edition.

.DESCRIPTION
An crafty command-line interface to open the page viewer of the Asahi Shimbun.

To run this script via a windows command shell script
to avoid the execution policy:
`powershell -ExecutionPolicy RemoteSigned -File %~dpn0.ps1`

.PARAMETER edition
An edition of the newspaper.
"" ( = morning ) or "ev" ( = evening ) edition.

.PARAMETER issue
An issue of the newspaper.
"" ( = latest ) or "yyyyMMdd" ( = specified ) issue.

.PARAMETER duration
An issue of the newspaper (N days ago).
It is allowed -14 to 0.

.PARAMETER help
Indicates this help.

.LINK
https://www.asahi.com/

# .EXAMPLE
# asahi.ps1

# .EXAMPLE
# asahi.ps1 ev

# .EXAMPLE
# asahi.ps1 -issue 20180101

# .EXAMPLE
# asahi.ps1 -duration -14

# .EXAMPLE
# asahi.ps1 -edition ev -issue 20180101

# .EXAMPLE
# asahi.ps1 -help

#>

# Initializing...
param(
    [AllowNull()] [AllowEmptyString()] [ValidateSet("", "ev")] [string] $edition = "",
    [string] $issue,
    [ValidateRange(-14, 0)] [int] $duration = 0,
    [switch] $help
)
if ($help) {
    Get-Help -Detailed $MyInvocation.MyCommand.Path
    return
}
[DateTime] $date = [DateTime]::Now # The basis date.

if ($issue) {
    [DateTime] $date = [DateTime]::ParseExact($issue, "yyyyMMdd", $null)
}
elseif (! $duration) {
    # Detecting latest issue...

    if (
        # A morning edition is published in 05:00 today.
        ( $edition -ne "ev" -and ( [int] $date.ToString("%H") -lt  5 ) ) -or
        # An evening edition is published in 17:00 today.
        ( $edition -eq "ev" -and ( [int] $date.ToString("%H") -lt 17 ) )
    ) {
        # The latest issue is published in yesterday.
        $duration --
    }
}

# If the specified publish date is Sunday... (It is not comply with holidays!)
if (
    $edition -eq "ev" -and
    $date.AddDays($duration).ToString(
        "ddd", [CultureInfo]::CreateSpecificCulture("en-US")
    ) -eq "Sun"
) {
    # The latest issue is published in the preceding business day.
    $duration --
}

# Buld the issue...
$issue = $date.AddDays($duration).ToString("yyyyMMdd")

# Open URL of the issue/edition...
# "invoke-item" is not available for the purpose
start "http://www.asahi.com/shimen/redirect/$issue$edition.htm"