package fic

import (
	"database/sql"
	"time"
)

// Claim represents an issue, a bug or a ToDo item.
type Claim struct {
	Id          int64     `json:"id"`
	Subject     string    `json:"subject"`
	IdTeam      *int64    `json:"id_team"`
	IdAssignee  *int64    `json:"id_assignee"`
	Creation    time.Time `json:"creation"`
	State       string    `json:"state"`
	Priority    string    `json:"priority"`
}

// GetClaim retrieves the claim with the given identifier.
func GetClaim(id int) (c Claim, err error) {
	err = DBQueryRow("SELECT id_claim, subject, id_team, id_assignee, creation, state, priority FROM claims WHERE id_claim = ?", id).Scan(&c.Id, &c.Subject, &c.IdTeam, &c.IdAssignee, &c.Creation, &c.State, &c.Priority)
	return
}

// GetClaims returns a list of all Claim registered in the database.
func GetClaims() (res []Claim,  err error) {
	var rows *sql.Rows
	if rows, err = DBQuery("SELECT id_claim, subject, id_team, id_assignee, creation, state, priority FROM claims"); err != nil {
		return
	}
	defer rows.Close()

	for rows.Next() {
		var c Claim
		if err = rows.Scan(&c.Id, &c.Subject, &c.IdTeam, &c.IdAssignee, &c.Creation, &c.State, &c.Priority); err != nil {
			return
		}
		res = append(res, c)
	}
	err = rows.Err()

	return
}

// GetClaims returns a list of all Claim registered for the Team.
func (t Team) GetClaims() (res []Claim,  err error) {
	var rows *sql.Rows
	if rows, err = DBQuery("SELECT id_claim, subject, IdTeam, id_assignee, creation, state, priority FROM claims WHERE IdTeam = ?", t.Id); err != nil {
		return nil, err
	}
	defer rows.Close()

	for rows.Next() {
		var c Claim
		if err = rows.Scan(&c.Id, &c.Subject, &c.IdTeam, &c.IdAssignee, &c.Creation, &c.State, &c.Priority); err != nil {
			return
		}
		res = append(res, c)
	}
	err = rows.Err()

	return
}

// NewClaim creates and fills a new struct Claim and registers it into the database.
func NewClaim(subject string, team *Team, assignee *ClaimAssignee, priority string) (Claim, error) {
	var tid *int64
	if team == nil {
		tid = nil
	} else {
		tid = &team.Id
	}

	var aid *int64
	if assignee == nil {
		aid = nil
	} else {
		aid = &assignee.Id
	}

	if res, err := DBExec("INSERT INTO claims (subject, id_team, id_assignee, creation, state, priority) VALUES (?, ?, ?, ?, ?, ?)", subject, tid, aid, time.Now(), "new", priority); err != nil {
		return Claim{}, err
	} else if cid, err := res.LastInsertId(); err != nil {
		return Claim{}, err
	} else {
		return Claim{cid, subject, tid, aid, time.Now(), "new", priority}, nil
	}
}

// GetTeam returns the Team linked to the issue, if any.
func (c Claim) GetTeam() (*Team, error) {
	if c.IdTeam == nil {
		return nil, nil
	} else if t, err := GetTeam(*c.IdTeam); err != nil {
		return nil, err
	} else {
		return &t, nil
	}
}

// SetTeam defines the Team that is linked to this issue.
func (c Claim) SetTeam(t Team) {
	c.IdTeam = &t.Id
}

// Update applies modifications back to the database.
func (c Claim) Update() (int64, error) {
	if res, err := DBExec("UPDATE claims SET subject = ?, id_team = ?, id_assignee = ?, creation = ?, state = ?, priority = ? WHERE id_claim = ?", c.Subject, c.IdTeam, c.IdAssignee, c.Creation, c.State, c.Priority, c.Id); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// Delete the issue from the database.
func (c Claim) Delete() (int64, error) {
	if res, err := DBExec("DELETE FROM claims WHERE id_claim = ?", c.Id); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// ClearClaims removes all issues from database.
func ClearClaims() (int64, error) {
	if res, err := DBExec("DELETE FROM claims"); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// ClaimDescription represents some text describing an issue.
type ClaimDescription struct {
	Id          int64     `json:"id"`
	// IdAssignee stores the user who handle the claim (or 0 if nobody handles it).
	IdAssignee  int64     `json:"id_assignee"`
	// Content is the raw description.
	Content     string    `json:"content"`
	// Date is the timestamp when the description was written.
	Date        time.Time `json:"date"`
}

// GetDescriptions returns a list of all descriptions stored in the database for the Claim.
func (c Claim) GetDescriptions() (res []ClaimDescription,  err error) {
	var rows *sql.Rows
	if rows, err = DBQuery("SELECT id_description, id_assignee, content, date FROM claim_descriptions WHERE id_claim = ?", c.Id); err != nil {
		return nil, err
	}
	defer rows.Close()

	for rows.Next() {
		var d ClaimDescription
		if err = rows.Scan(&d.Id, &d.IdAssignee, &d.Content, &d.Date); err != nil {
			return
		}
		res = append(res, d)
	}
	err = rows.Err()

	return
}

// AddDescription append in the database a new description; then returns the corresponding structure.
func (c Claim) AddDescription(content string, assignee ClaimAssignee) (ClaimDescription, error) {
	if res, err := DBExec("INSERT INTO claim_descriptions (id_claim, id_assignee, content, date) VALUES (?, ?, ?, ?)", c.Id, assignee.Id, content, time.Now()); err != nil {
		return ClaimDescription{}, err
	} else if did, err := res.LastInsertId(); err != nil {
		return ClaimDescription{}, err
	} else {
		return ClaimDescription{did, assignee.Id, content, time.Now()}, nil
	}
}

// Update applies modifications back to the database
func (d ClaimDescription) Update() (int64, error) {
	if res, err := DBExec("UPDATE claim_descriptions SET id_assignee = ?, content = ?, date = ? WHERE id_description = ?", d.IdAssignee, d.Content, d.Date, d.Id); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// Delete the description in the database.
func (d ClaimDescription) Delete() (int64, error) {
	if res, err := DBExec("DELETE FROM claim_descriptions WHERE id_description = ?", d.Id); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// ClaimAssignee represents a user that can handle claims.
type ClaimAssignee struct {
	Id   int64  `json:"id"`
	Name string `json:"name"`
}

// GetAssignee retrieves an assignee from its identifier.
func GetAssignee(id int64) (a ClaimAssignee, err error) {
	err = DBQueryRow("SELECT id_assignee, name FROM claim_assignees WHERE id_assignee = ?", id).Scan(&a.Id, &a.Name)
	return
}

// GetAssignees returns a list of all assignees found in the database.
func GetAssignees() (res []ClaimAssignee, err error) {
	var rows *sql.Rows
	if rows, err = DBQuery("SELECT id_assignee, name FROM claim_assignees"); err != nil {
		return
	}
	defer rows.Close()

	for rows.Next() {
		var a ClaimAssignee
		if err = rows.Scan(&a.Id, &a.Name); err != nil {
			return
		}
		res = append(res, a)
	}
	err = rows.Err()

	return
}

// NewClaimAssignee creates and fills a new struct ClaimAssignee and registers it into the database.
func NewClaimAssignee(name string) (ClaimAssignee, error) {
	if res, err := DBExec("INSERT INTO claim_assignees (name) VALUES (?)", name); err != nil {
		return ClaimAssignee{}, err
	} else if aid, err := res.LastInsertId(); err != nil {
		return ClaimAssignee{}, err
	} else {
		return ClaimAssignee{aid, name}, nil
	}
}

// Update applies modifications back to the database
func (a ClaimAssignee) Update() (int64, error) {
	if res, err := DBExec("UPDATE claim_assignees SET name = ? WHERE id_assignee = ?", a.Name, a.Id); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// Delete the assignee in the database.
func (a ClaimAssignee) Delete() (int64, error) {
	if res, err := DBExec("DELETE FROM claim_assignees WHERE id_assignee = ?", a.Id); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// ClearAssignees removes all assignees from database.
func ClearAssignees() (int64, error) {
	if res, err := DBExec("DELETE FROM claim_assignees"); err != nil {
		return 0, err
	} else if nb, err := res.RowsAffected(); err != nil {
		return 0, err
	} else {
		return nb, err
	}
}

// GetAssignee returns the assignee assigned to the claim.
func (c Claim) GetAssignee() (*ClaimAssignee, error) {
	if c.IdAssignee == nil {
		return nil, nil
	} else if a, err := GetAssignee(*c.IdAssignee); err != nil {
		return nil, err
	} else {
		return &a, nil
	}
}

// SetAssignee defines the assignee that'll handle the claim.
func (c Claim) SetAssignee(a ClaimAssignee) {
	c.IdAssignee = &a.Id
}