package control

import "encoding/json"

// Named payloads for the commands other surfaces decode. A command used
// to declare its output inline, so the web type-asserted map keys and
// nothing tied what a command emits to what a client reads (#126).

// Created is what issue create, issue comment and mr comment emit.
type Created struct {
	Number int64 `json:"number"`
}

// MRCreated is what mr create emits.
type MRCreated struct {
	Number    int64     `json:"number"`
	HeadSHA   string    `json:"head_sha"`
	StackedOn *stackRef `json:"stacked_on,omitempty"`
}

// IssueShow is issue show's payload: the issue and its comments.
type IssueShow struct {
	issueOut
	Comments []commentOut `json:"comments,omitempty"`
}

// MRShow is mr show's payload.
type MRShow struct {
	mrOut
	Checks            []CheckOut   `json:"checks,omitempty"`
	Combined          string       `json:"checks_combined,omitempty"`
	UnresolvedThreads int          `json:"unresolved_threads,omitempty"`
	Commits           []CommitOut  `json:"commits,omitempty"`
	Comments          []commentOut `json:"comments,omitempty"`
	Reviews           []ReviewOut  `json:"reviews,omitempty"`
	// Gates is set while the merge request is open.
	Gates *GatesOut `json:"gates,omitempty"`
}

// OwnersOut is a set of changed files still waiting on an approval from
// one of their CODEOWNERS.
type OwnersOut struct {
	Files  []string `json:"files"`
	Owners []string `json:"owners"`
}

// GatesOut is what a merge request has to pass to merge, and where it
// stands: the same computation mr merge refuses on, so nothing is
// learned at the refusal that mr show did not say (#199).
type GatesOut struct {
	Draft              bool        `json:"draft,omitempty"`
	ApprovalsRequired  int         `json:"approvals_required"`
	Approvals          []string    `json:"approvals,omitempty"` // fresh, from reviewers who count
	ChangesRequested   []string    `json:"changes_requested,omitempty"`
	CodeownersRequired bool        `json:"codeowners_required"`
	OwnersOutstanding  []OwnersOut `json:"owners_outstanding,omitempty"`
	ResolvedRequired   bool        `json:"resolved_required"`
	OpenThreads        int         `json:"open_threads"`
	ChecksRequired     bool        `json:"checks_required"`
	Checks             string      `json:"checks,omitempty"` // combined status; "" when none reported
	FastForward        bool        `json:"fast_forward"`
	Unmet              []string    `json:"unmet,omitempty"`
}

// ReviewOut is one review on a merge request.
type ReviewOut struct {
	Reviewer string `json:"reviewer"`
	Verdict  string `json:"verdict"`
	Stale    bool   `json:"stale"`
	// Counts reports whether this verdict decides the merge gates. A
	// reader may review a public merge request; only someone who can
	// write to the repository decides whether it merges. Without this the
	// page would show an approval the gate ignores, and the difference
	// would be invisible until a merge was refused (#147).
	Counts    bool   `json:"counts"`
	CreatedAt string `json:"created_at"`
}

// CheckOut is one commit status on a merge request head.
type CheckOut struct {
	Context   string `json:"context"`
	State     string `json:"state"`
	URL       string `json:"url,omitempty"`
	UpdatedAt string `json:"updated_at"`
	Duration  string `json:"duration,omitempty"` // CI checks only, once finished
}

// CommitOut is one commit a merge request carries.
type CommitOut struct {
	SHA     string `json:"sha"`
	Subject string `json:"subject"`
}

// jsonStrings renders a string slice as a JSON array, for the event data
// the webhook payload carries. A nil slice is [], never null: a consumer
// iterating the field should not have to special-case one of them.
func jsonStrings(ss []string) string {
	if ss == nil {
		ss = []string{}
	}
	raw, err := json.Marshal(ss)
	if err != nil {
		return "[]"
	}
	return string(raw)
}