tag = {
    ( "feat"
    | "fix"
    | "refactor"
    | "perf"
    | "style"
    | "test"
    | "build"
    | "ops"
    | "docs"
    | "chore"
    | "merge"
    | "revert"
    )
}

scope = { (!"(" ~ !")" ~ ANY)+ }

breaking_change = { "!" }

subject = { (!empty_separator_line ~ ANY)+ }

title = {
    tag
    ~ ("(" ~ scope ~ ")")?
    ~ (breaking_change)?
    ~ ": "
    ~ subject
}

body = { (!empty_separator_line ~ ANY)+ }

footer = { (!empty_separator_line ~ ANY)+ }

message = {
    title{, 50} ~
    (empty_separator_line ~ body)? ~
    (empty_separator_line ~ footer)?
}

main = _{ SOI ~ message ~ EOI }
empty_separator_line = _{ NEWLINE ~ NEWLINE }