Calling on jq gurus again. How can I find the index

Question

łibfitź.r14.a

Calling on jq gurus again. How can I find the index

of an array element by the value of some key inside this element?
Basically, given this
"array": [
{ "key": "value" },
{ "key": "bad-value" },
{ "key": "very-bad-value" }
]
I want jq to return the numeric index of the element that has bad-value as the value of key, i.e. return 1
I could do that in Python or another language, sure, but jq should have a way of doing this