package model

import "time"

// Quiz target kinds.
const (
	QuizChapter      = "chapter"
	QuizLecture      = "lecture"
	QuizConversation = "conversation"
	QuizStandalone   = "standalone"
)

// Attempt states, as seen by the person taking the quiz.
const (
	QuizNotStarted = "not_started"
	QuizInProgress = "in_progress"
	QuizCompleted  = "completed"
)

// Quiz is a set of multiple-choice questions, optionally tied to a page.
type Quiz struct {
	ID          string  `json:"id"`
	Title       string  `json:"title"`
	Description string  `json:"description"`
	TargetKind  string  `json:"target_kind"`
	TargetPath  *string `json:"target_path,omitempty"`
	TargetTitle string  `json:"target_title"`
	// TargetYear is the lecture or conversation's year, for grouping.
	TargetYear  *int       `json:"target_year,omitempty"`
	PublishedAt *time.Time `json:"published_at,omitempty"`
	CreatedAt   time.Time  `json:"created_at"`
	UpdatedAt   time.Time  `json:"updated_at"`

	QuestionCount int `json:"question_count"`
	// Admin-only counters.
	AttemptCount   int `json:"attempt_count,omitempty"`
	CompletedCount int `json:"completed_count,omitempty"`

	Questions []QuizQuestion `json:"questions,omitempty"`
}

// QuizQuestion is one question. Prompt and option bodies carry the same
// formatting markers as the rest of the admin text.
type QuizQuestion struct {
	ID          string `json:"id"`
	Ord         int    `json:"ord"`
	Prompt      string `json:"prompt"`
	Explanation string `json:"explanation,omitempty"`
	// Multi questions ask for every correct option ("select all that apply").
	Multi   bool         `json:"multi"`
	Options []QuizOption `json:"options"`
}

// QuizOption is one choice. IsCorrect is nil whenever the reader must not
// know it yet — every response to someone mid-attempt.
type QuizOption struct {
	ID        string `json:"id"`
	Ord       int    `json:"ord"`
	Body      string `json:"body"`
	IsCorrect *bool  `json:"is_correct,omitempty"`
}

// QuizStatus is the caller's progress on a quiz.
type QuizStatus struct {
	State    string `json:"state"`
	Answered int    `json:"answered"`
	Total    int    `json:"total"`
	Score    *int   `json:"score,omitempty"`
}

// QuizCard is a quiz plus the caller's progress, for buttons and lists.
type QuizCard struct {
	Quiz
	My QuizStatus `json:"my"`
}

// QuizPlay is the next step of an attempt: the current question, or Done.
type QuizPlay struct {
	QuizID   string        `json:"quiz_id"`
	Title    string        `json:"title"`
	Answered int           `json:"answered"`
	Total    int           `json:"total"`
	Done     bool          `json:"done"`
	Question *QuizQuestion `json:"question,omitempty"`
}

// QuizResultItem is one question on a results screen.
type QuizResultItem struct {
	QuizQuestion
	ChosenOptionIDs []string `json:"chosen_option_ids"`
	IsCorrect       bool     `json:"is_correct"`
	ResponseMs      *int     `json:"response_ms,omitempty"`
}

// QuizResult is a finished attempt.
type QuizResult struct {
	Quiz        Quiz             `json:"quiz"`
	Score       int              `json:"score"`
	Total       int              `json:"total"`
	StartedAt   time.Time        `json:"started_at"`
	CompletedAt *time.Time       `json:"completed_at,omitempty"`
	TotalMs     int              `json:"total_ms"`
	Items       []QuizResultItem `json:"items"`
}

// QuizParticipant is one person's attempt, for the admin participants list.
type QuizParticipant struct {
	UserID      string     `json:"user_id"`
	Handle      string     `json:"handle"`
	Name        string     `json:"name"`
	AvatarURL   *string    `json:"avatar_url,omitempty"`
	StartedAt   time.Time  `json:"started_at"`
	CompletedAt *time.Time `json:"completed_at,omitempty"`
	Answered    int        `json:"answered"`
	Score       int        `json:"score"`
	Total       int        `json:"total"`
	TotalMs     int        `json:"total_ms"`
}

// QuizOptionStat is how often one option was chosen.
type QuizOptionStat struct {
	QuizOption
	Picks int `json:"picks"`
}

// QuizQuestionStat aggregates every response to one question.
type QuizQuestionStat struct {
	ID       string           `json:"id"`
	Ord      int              `json:"ord"`
	Prompt   string           `json:"prompt"`
	Multi    bool             `json:"multi"`
	Answered int              `json:"answered"`
	Correct  int              `json:"correct"`
	AvgMs    int              `json:"avg_ms"`
	MedianMs int              `json:"median_ms"`
	Options  []QuizOptionStat `json:"options"`
}