<#
.SYNOPSIS
    提交前共享检查：推断变更文件所属模块，校验提交信息格式。

.DESCRIPTION
    读取 git diff 中变更的文件，根据 hooks/commit-module-mappings.json
    推断模块，然后校验提交信息是否符合 [模块][类型]: 描述 格式。

.PARAMETER Message
    待校验的提交信息。

.EXAMPLE
    .\docs\hooks\commit-check.ps1 -Message "[entity][docs]: 补充实体池说明"
#>

param(
    [Parameter(Mandatory = $true)]
    [string]$Message
)

$ErrorActionPreference = 'Stop'

$mappingFile = Join-Path $PSScriptRoot 'commit-module-mappings.json'
if (-not (Test-Path $mappingFile)) {
    Write-Error "Module mapping file not found: $mappingFile"
    exit 1
}

$mapping = Get-Content $mappingFile -Raw | ConvertFrom-Json

function Get-ChangedFiles {
    $staged = (cmd /c "git diff --cached --name-only 2>nul") -split "`r?`n" | Where-Object { $_ }
    if (-not $staged) { $staged = @() }

    $unstaged = (cmd /c "git diff --name-only 2>nul") -split "`r?`n" | Where-Object { $_ }
    if (-not $unstaged) { $unstaged = @() }

    $all = @($staged) + @($unstaged) | Select-Object -Unique | Where-Object { $_ }
    return $all
}

function Get-ModuleForFile($file) {
    foreach ($entry in $mapping.mappings) {
        if ($file -match $entry.pattern) {
            return $entry.module
        }
    }
    return $null
}

function Get-ModulesFromChangedFiles($files) {
    $modules = @()
    foreach ($file in $files) {
        $module = Get-ModuleForFile $file
        if ($module) {
            $modules += $module
        }
    }
    return $modules | Select-Object -Unique
}

function Test-CommitMessage($message, $modules) {
    if ($message -notmatch '^\[([^\]]+)\]\[([^\]]+)\]:\s*(.+)$') {
        return @{ IsValid = $false; Reason = '提交信息格式应为：[模块][类型]: 描述' }
    }

    $msgModule = $Matches[1]
    $msgType = $Matches[2]
    $msgDesc = $Matches[3]

    if (-not $msgDesc) {
        return @{ IsValid = $false; Reason = '提交信息缺少描述内容' }
    }

    if ($mapping.validTypes -notcontains $msgType) {
        return @{ IsValid = $false; Reason = "无效的类型 '$msgType'。有效类型：$($mapping.validTypes -join ', ')" }
    }

    if ($modules -and $modules -notcontains $msgModule) {
        Write-Warning "提交信息中的模块 [$msgModule] 与变更文件推断的模块 [$($modules -join ', ')] 不一致，请确认是否 intentional。"
    }

    return @{ IsValid = $true; Reason = '' }
}

$files = Get-ChangedFiles
if (-not $files) {
    Write-Host "未检测到变更文件。" -ForegroundColor Yellow
    exit 0
}

$modules = Get-ModulesFromChangedFiles $files

Write-Host "变更文件："
$files | ForEach-Object { Write-Host "  - $_" }

if ($modules) {
    Write-Host "推断模块：$($modules -join ', ')"
}
else {
    Write-Warning "未能从变更文件推断出模块，请检查提交信息是否手动指定了正确模块。"
}

$result = Test-CommitMessage $Message $modules
if (-not $result.IsValid) {
    Write-Error $result.Reason
    exit 1
}

Write-Host "提交信息格式正确。" -ForegroundColor Green
exit 0